Publications

In the realm of science education, particularly biology education, keeping abreast of new discoveries and insights is of paramount importance. During the 20222023 school year, we sent 21 scientific newsletters (SNs) via WhatsApp dealing with contemporary biological topics to 901 biology teachers in junior high schools and high schools. The aim of this survey study was to investigate how teachers perceive the possible impact of these SNs on both their own professional development and their students. We sent a questionnaire to the teachers, 110 of which were filled out. The key finding from the teachers responses was that the primary and most crucial contribution of the SNs lies in enhancing teachers biological disciplinary knowledge, contributing to their own professional development, and enhancing their students biological disciplinary knowledge. The SNs were notably less significant for teachers in terms of elevating their own or their students scientific literacy. Future examination of teachers experiences and insights may lead to a deeper understanding of how SNs influence teaching methodologies and content knowledge, and impact instructional effectiveness.

Background: Influential philosophers have suggested that interdisciplinarity is crucial for ecosystem management and scientific practice, and for education to democracy. However, a historical review of the rise of disciplines points at their compartmentalization in schools. An analysis of core construct categories of three disciplines, shows that this compartmentalization may decrease when dialogic argumentation is enacted. This background led us to launch an interdisciplinary program in schools. In previous publications, we identified multiple constraints in its implementation and listed design principles for affording interdisciplinary dialogic argumentation. Method: We adopt a narrative approach to analyze classroom talk, and ask whether and how interdisciplinary processes emerge in this talk. Findings: Students maintain dialogic argumentation around Interdisciplinary Social Dilemmas, but guidance is necessary for integrating knowledge from different disciplines. When the teacher is attentive to students unarticulated references to disciplinary ideas, she may subtly guide the emergence of interdisciplinary dialogic argumentation. Often, the teacher misses those opportunities and declaims the integration of knowledge in a non-dialogic talk. Contribution: Dialogic Education is crucial for the success of interdisciplinary programs in schools, but the actual emergence of interdisciplinary processes depends on the handling of organizational and institutional constraints, on huge design efforts, and on subtle guidance.

Evolution is a fundamental part of biology and thus it is essential that biology preservice teachers understand and accept it. The relationship between knowledge and acceptance of evolution, and specifically human evolution, has not been fully investigated in Israel. We sought to learn about that relationship amongst Israeli Jewish religious preservice science teachers. Twenty-three religious preservice teachers answered knowledge questions before and after participating in a human evolution activity and completed an acceptance questionnaire (I-SEA). In addition, eleven of them were interviewed regarding their knowledge of evolution and four were interviewed regarding their acceptance of evolution a few months after participating in the activity. Our main findings were that the relationship between knowledge and acceptance of evolution was not always one-to-one. The preservice teachers whose evolution knowledge is high and have firm religious faith accept the theory of evolution and are willing and eager to teach it. In addition, preservice teachers might have made a shift in their understanding of human evolution and thus accepted human evolution more due to the activity. More teacher training and exposure to evolution content and pedagogy are needed so that when preservice teachers will become in-service teachers they will teach evolution without hesitance.

Education must go beyond only countering essentialist and deterministic views of genetics.

The contribution of school curricula to public understanding and acceptance of evolution is still mostly unknown, due to the scarcity of studies that compare the learning goals present in different curricula. To overcome this lack of data we analysed 19 school curricula (18 European and one from Israel) to study the differences regarding the inclusion of learning goals targeting evolution understanding. We performed a quantitative content analysis using the Framework for the Assessment of school Curricula on the presence of Evolutionary concepts (FACE). For each country/region we analysed what this educational system considered the minimum evolution education a citizen should get. Our results reveal that: (i) the curricula include less than half of the learning goals considered important for scientific literacy in evolution; (ii) the most frequent learning goals address basic knowledge of evolution; (iii) learning goals related with the processes that drive evolution are often not included or rarely mentioned; (iv) evolution is most often not linked to its applications in everyday life. These results highlight the need to rethink evolution education across Europe.

Classroom interactions emerging from socioscientific argumentation may be incompatible with the traditional definitions of learning, thus creating tension and potentially undermining its implementation. Leveraging existing literature, we identify argumentative talk that shifts away from scientific content and toward subjective claims, as well as instances of unproductive argumentation as the points of incompatibility. We contend that attention to the degree of compatibility of enactments of socioscientific argumentation with traditional schooling practices may be necessary for substantive implementation. The role of teachers and students interactional moves in relation to this compatibility is qualitatively examined using two analytical frameworks related to the content and form of the students arguments. To generate practical implications with empirical foundations, compatibility is examined in teacher-led and peer-led argumentation. In teacher-led argumentation, we show that the degree of incompatibility can be managed when teachers extend their elicitation of responses with follow-up interrogative questioning, leading students to rely more on scientific knowledge. In peer-led argumentation, incompatibility can be identified when the argumentation collapses into confrontational disagreement or uncritical agreement, obscuring instances in which students rely on scientific knowledge. We discuss the significance of productive talk moves as a way to advance from incompatibility with traditional schooling toward integrating socioscientific argumentation as a core instructional practice.

Large data sets invite students to engage in scientific practices such as question asking, identifying correlations, using visualizations, and practicing data literacy in an authentic context. However, authentic data sets are rarely introduced in the biology classroom. We prepared an online inquiry activity based on authentic gross characteristics of a gazelle data set. These included gazelles weight, location (longitude and latitude), collection date, and measured lengths of body parts. In constructing the activity, we considered the following design principles: use of high-quality authentic data, choice of a wide data set to allow multiple research questions, and exposure of the participants to basic data science tools. The activity starts with an introduction to data sets and guided data analysis, and it ends with independent research of a large gazelle data set. The activity was experienced by 121 teachers and was found to promote higher-order research questions. Before the activity, most of the teachers questions focused on gazelle propertiesfirst-order questions, according to Dillons (1984) classification of research questions. Following the activity, most questions belonged to the comparison and contingencies categories (second- and third-order questions, respectively). Thus, this activity might serve to expand the biology teachers toolbox in teaching inquiry and data literacy.

Background The presumed conflict between religion and evolution is considered one of the main causes for rejection of evolution worldwide. It has been shown that when students perceived conflict is not answered, they may not accept evolution. However, there is a debate in the literature whether teachers should relate to students religious faith in evolution class, although teachers tend to agree that it should be related. The aim of this study was to explore the attitudes of scientists and teachers, toward relating to religion when teaching evolution. Results When scientists (n=124) were asked in an online survey whether teachers should relate to religion when teaching evolution, most scientists said teachers should not relate to religion, in contrary to teachers who were asked the same question and said that teachers should relate to religion. When religious teachers (n=10) and scientists (n=10) were asked the same questionall the religious teachers agreed that teachers should relate to religion, emphasizing mainly the importance of connecting to the students inner world, preparing students for the future, etc. Most religious scientists also agreed, although they were more hesitant and emphasized the challenges and limitations of relating to religion in a science class. When asked how to relate to the issue, the teachers emphasized the importance of relating to the students culture and self-choice. Moreover, they took responsibility and emphasized it is their role to provide a proper response to their students. Most interviewed scientists emphasized that the boundaries between science and religion should be emphasized clearly by the teacher, and some suggested that biology teachers themselves should not discuss the issue, but that an external figure such as a rabbi or the religion/bible teacher should do it. Conclusions When discussing the issue of relating to religion in a science class, the differences between scientists and teachers that were identified here emphasize the need to relate to teachers experiences in this academic discussion, as they are aware of their students difficulties. In addition, it is important to consider the attitudes of religious scientists and teachers, as they demonstrate the possible co-existence between religion and science in their own life, thus they understand the conflict and may have practical solutions to it. Teachers professional development programs in this issue, may help teachers face with the limitations and challenges that the presumed conflict between religion and evolution may create.

Past research has shown various benefits of combining the argumentative and the dialogic in cognitive development. However, it has also shown that attempts to implement dialogic argumentation in school fail to leave a sustainable impact. One reason for this situation is related to the lack of explicit knowledge about how to design and organize dialogical activities in realistic school settings. The present study addresses this lacuna while putting forward interdisciplinarity as a promising venue for promoting student dialogue and argumentation. We first elaborate on the connection between dialogic argumentation and interdisciplinarity, review the relevant literature on instructional and task design and then suggest a configuration of the design principles needed to be developed: these are content-related principles, pedagogy-related principles and organization-related principles. This is followed by an illustration of how specific design principles of these types emerged from and are reflected in task-design practices of project team of researchers in science, mathematics and philosophy education. Finally, we show that while the focus on interdisciplinarity seems to narrow the issue of the implementation of dialogue and argumentation in schools, it in fact opens it and provides instructional design principles in complex educational projects relevant to the society.

Background: The presumed conflict between religion and evolution is considered one of the main causes of rejection of evolution worldwide. However, there is a unique group of religious people who accept, study, and teach evolution. The aim of this study was to gain a better understanding of these individuals conception of the relationship between evolution and religion, and the factors that influenced this conception. Religious biology teachers (n=10) and scientists (n=10) were surveyed and interviewed about their conception of evolution and religion and the factors that influenced it. Results: The study population demonstrated that reconciling science and religion was possible for them. The interpretation of the bible as moral guidance, and not as a science book, was found to be a main idea in the participants conception. Most participants said that their conception of evolution was influenced by their parents and teachers approach to science. Participants who had rejected evolution in the past emphasized that exposure to scientific knowledge alone was not enough to counter this rejection, whereas exposure to the possible compatibility between religion and evolution promoted their acceptance. Conclusions: These findings suggest the importance of exposing teachers to different approaches to the relationship between evolution and religion. Implementation of the study conclusions in professional development programs may help teachers promote religiously affiliated students better learning of evolution and a meaningful learning of science in general.

Molecular animations can be beneficial as teaching tools for genomics education; however, barriers to their effective implementation remain. This article proposes informed design guidelines from the perspective of the animator that may assist others to effectively communicate scientific concepts to their respective audiences and communities.

This edited volume presents the current state of the art of genetics education and the challenges it holds for teaching as well as for learning. It addresses topics such as how genetics should be taught in order to provide students with a wide and connected view of the field. It gives in-depth aspects that should be considered for teaching genetics and the effect on the students understanding. This book provides novel ideas for biology teachers, curriculum developers and researchers on how to confront the presented challenges in a way that may enable them to advance genetics education in the 21st century. It reviews the complexity of teaching and learning genetics, largely overlooked by biology textbooks and classroom instruction. It composes a crucial component of scientific literacy.

The importance of promoting genetics understanding in high-school students lies in enabling them, as future citizens, to think critically and make informed decisions regarding genetics-related issues. Students should know how genetics knowledge has been acquired and its applications to societal issues. However, high-school students rarely have access to current technologies and practices used in genetic research; therefore, their opportunities to be exposed to the way genetics knowledge is gained and applied today are limited. One way to provide these opportunities is through authentic scientific experiences practiced in schools, i.e., experiences that are as similar as possible to the way science is practiced by scientists. This chapter reviews the characteristics of authentic scientific experiences and examples of authentic science experiences in genetics that have been practiced in high schools: hands-on experiments, studentteacherscientist partnership, design-based learning, use of bioinformatics tools, and learning with adapted primary literature. Each example is related to a different research context in which genetic concepts are applied. Through these examples, we demonstrate the benefits of authentic scientific experiences to genetics learning. The challenges in implementing authentic experiences in genetics in high school, and the role of scientists in the process of developing and carrying them out are discussed.

Human evolution is a sensitive and controversial topic, which might explain why it is not included in science curricula or textbooks in many countries. We prepared an online student-centered human evolution activity dealing with lactose tolerance. In constructing the activity, we considered the following design principles: a medical issue connected to students' lives, a noncontentious topic of human evolution, and a one-step genetic example that can be demonstrated by basic bioinformatics tools. The activity consists of four units dealing with the activity of the enzyme lactase in our small intestine, the differences in lactose tolerance in people from different origins, the genetic foundation of lactose tolerance, and an extension unit dealing with the control of lactase gene expression. The activity was experienced by a pilot group of approximately 100 students, preservice and in-service teachers who showed great interest in the genetics of a trait that has undergone evolutionary changes. We noted the need for a teacher as mediator while students perform the activity. We suggest using the activity in the context of evolution, genetics, or when teaching about systems of the human body, either all units in succession or as a modular activity.

This study seeks to understand why dialogic argumentation has not been adopted as a legitimate means of instruction by science teachers. To answer this question, this qualitative case study examines the mutually constitutive relationships between macrolevel phenomena, such as the takenforgranted institutional mandates that teachers and schools call upon to maintain their legitimacy in society, and microlevel routinized teacherstudent classroom interactions. Integrating ethnography with the analysis of classroom interactions, we seek to capture the social structuring that informs instruction and classroom interactions. Based on an inductive analysis of observations, interviews with teachers, and documents, three types of macrolevel institutional logics that mediate against the implementation of dialogic argumentation emerged. These included the logics of (a) accountability, (b) tracking, and (c) the profession. These logics give rise to instructional practices that run counter to the pursuit of dialogic argumentation. Classroom observations were analyzed to examine how these logics are conveyed through institutionally bounded interactions between teachers and students. Shaped by these institutional logics, instruction in classrooms is narrowed to mostly direct instruction of terminology and absolute facts, and is stratified into various status levels according to classroom tracking. We argue that teachers may resist dialogic argumentation primarily because it violates the fundamental rules, norms, and practices that grant them individual and organizational legitimacy. This contextualization of teacherstudent interactions as motivated by institutional logics may explain in greater detail the absence of dialogic argumentation from science classrooms.

Calls have been made to give K-12 teachers and students access to current methods used in biological research, including advanced microscopy. The scanning electron microscope (SEM) is a powerful tool that can be used for either remote or onsite inquiry experiences for students. To use this microscope in a way that promotes students' understanding of biological concepts, teachers should be informed about its capabilities, benefits and limitations as an instructional tool. Therefore, we introduced SEM to in-service biology teachers through a teacher-training workshop where they experienced activities using the SEM. We then assessed their views on the possible benefits and challenges of the SEM in high-school biology class, and particularly while teaching the relationships between structure and function. The participants' insights are described and discussed here, shedding light on what biology teachers should take into consideration while planning and engaging their students in activities using the SEM. © ISLS.

Lately, eLearning has substituted traditional forms of teaching and learning. However, little is known about the possible link between eLearning, addressing epistemic knowledge and scientific practices. We aimed to analyze teachers' re-designed eLearning units and examine the extent to which high school biology teachers address epistemic knowledge and scientific practices in the Personalized Teaching and Learning, PeTeL platform. We qualitatively mapped the re-designed ecology and evolution eLearning units according to knowledge types and scientific practices. We found that a few teachers addressed epistemic knowledge in their re-designed eLearning units, and that questions that include only content knowledge, mostly lacked scientific practices. Thus, it seems that most of the teachers find epistemic knowledge difficult to address.

Introducing datasets in to the science classroom may facilitate developing scientific practices and epistemic thinking. However, authentic datasets are rarely used in high school, and little is known about biology teachers knowledge considerations regarding dataset - driven instruction. Here we investigated these knowledge considerations in high - school biology teachers. Forty teachers designed dataset - driven instruction units and completed open - ended questionnaires during a professional development workshop. Our analysis, based on the PISA framework of scientific literacy, indicated that although epistemic considerations were the most prominent of teachers' perceived benefits of dataset - driven instruction, they were less pronounced than content and procedural considerations in the instruction units that they designed. This suggests that although teachers recognize the value of epistemic thinking and see authentic datasets as a means to facilitate scientific literacy, further effort is needed to assist teachers in designing instruction units which better reflect these goals.

Evolution is a difficult topic to teach; teachers admit not having enough knowledge of evolution and they face student opposition to learning evolution, especially based on religious grounds. Teachers are therefore motivated to gain knowledge in the field of evolution. We conducted a 30-hour evolution teacher training course, which included scientific and pedagogical evolution knowledge, with 14 inservice teachers who represent the main religious/cultural sectors in the country. The aim of this research was to enrich our knowledge regarding students' opposition to learning evolution as reflected by their teachers-participants in the teacher training course, as well as the ways in which these teachers dealt with this opposition before and after the course. Our main findings were that 9 of the participating teachers underwent a transition during the course which gave them either the pedagogical tools or confidence to teach evolution, or to deal with their students' opposition to learning evolution stemming from religious beliefs. Four of the teachers expressed unwillingness to deal with this opposition. A more intensive course dealing with science and religion might have been even more significant for the teachers. Teacher training courses are a good opportunity for further science education research, they can help teachers overcome their students' conflicts with evolution and enable them to teach it without trepidation.

Evolution is one of the most controversial scientific issues worldwide, mainly because of the presumed conflict with religion, which also arises in school biology classes. Here, we surveyed biology teachers from different Jewish sectors in Israel about their experiences teaching evolution and their perspective on relating to students' religious faith. Information was collected using an online questionnaire that was answered by 97 teachers, and three focus groups of 9 teachers. Half of the teachers reported encountering student religious-based opposition, in traditional/religious schools more than in secular ones. The teachers indicated that students' religious faith may hinder their understanding of evolution, while teachers' own perception of the conflict influenced their attitude. Most of the teachers indicated their willingness to relate to their students' religious faith in class, mainly because of the importance of relating to students' inner world. Our research adds to the global interest in evolution education by shedding light on this topic in a Jewish population, which has been little studied. In addition, the study emphasises the importance of relating to teachers' experiences and perspective in the discussion on whether to relate to students' religious faith during science class, because teachers are the mediators of science to future citizens.

Communication of scientific information in the scientific community is achieved mainly through scientific texts. The scientific discourse is often referred to as a \u201cregister,\u201d a constellation of lexical and grammatical features that characterizes particular uses of language. Thus the language of different text genres (e.g. research articles, popular articles, books, etc.) varies as it is used in different contexts for different purposes. Research articles convey epistemological assumptions scientists operate with. Accordingly, these articles have evolved certain grammatical features, figures of speech and rhetorical patterns, which reflect on the scientists worldview and reasoning. In this chapter, we review the functionality of the scientific language in research articles for producing and organizing scientific knowledge. More specifically, we discuss how the language of research articles provides the semiotic means to build arguments throughout the article. Next we introduce Adapted Primary Literature (APL), an educational genre specifically designed to enable the use of research articles for learning biology in high-school. We discuss a pedagogical approach for promoting students and teachers epistemological understanding by using the APL as an apprenticeship genre, for learning the unique features of scientific language and of scientific communication and reasoning and for promoting scientific literacy.

The use of a molecular viewer to visualize proteins has become more prevalent in high schools in recent years. We relied on the foundations of two theoretical frameworks to analyze questions in two learning tasks designed for 10th- to 12th-grade biotechnology majors that make use of Jmol. The two theoretical frameworks were: (i) classification of scientific knowledge into content, procedural, and epistemic knowledge; and (ii) evaluation of the cognitive skills central to visual literacy in biochemistry. During the analysis, two sub-elements of procedural knowledge emerged from the data: (i) the visualization of molecular models, and (ii) the use of Jmol software features. Based on the theoretical frameworks and data analysis, we suggest a conceptualization of learning about proteins using a molecular viewer, where the scientific knowledge elements are integrated with the eight cognitive skills central to visual literacy in biochemistry. In addition, a model presenting a hierarchy for the knowledge elements and sub-elements is suggested. In this model, content knowledge is a basic requirement; without it, the other knowledge elements cannot be used. Moreover, the use of epistemic knowledge or Jmol software features is not possible without visualization of the molecular models, which requires content knowledge. This conceptualization is expected to facilitate the development of learning tasks, decrease the complexity of knowledge acquisition for students; it may also assist the teacher during the teaching process.

Over the past 50 years the Department of Science Teaching at the Weizmann Institute of Science in Israel was actively involved in all the components related to curriculum development, implementation, and research in science, mathematics, and computer science education: both learning and teaching. These initiatives are well designed and effective examples of long-term developmental and comprehensive models of reforms in the way science and mathematics are learned and taught. The 16 chapters of the book are divided into two key parts. The first part is on curriculum development in the sciences and mathematics. The second describes the implementation of these areas and its related professional development. Following these chapters, two commentaries are written by two imminent researchers in science and mathematics teaching and learning: Professor Alan Schonfeld from UC Berkeley, USA, and Professor Ilka Parchman from IPN at the University of Kiel, Germany. The book as a whole, as well as its individual chapters,

The conflict between acceptance and disapproval of evolution has led to obstacles in its teaching and learning. Other difficulties, such as both teachers and students alternative perceptions, student maturity in the face of learning this complicated topic, and teachers gaps in evolution knowledge, add to the difficulties in teaching and learning evolution. The aim of this study was to grasp the difficulties in the teaching and learning of evolution perceived by curriculum writers compared to those perceived by in-service junior high school science and technology teachers and high school biology teachers in Israel. The findings revealed a wide range of perceived difficulties in the teaching and learning of evolution, mainly in the fields of religion, teacher and student knowledge, student maturity, and alternative perceptions. A questionnaire distributed among in-service Israeli teachers added strength to interviews with the curriculum writers, with both referring to some of the same difficulties. However, some difficulties were heard only in the interviews. Curriculum writers were more concerned with questions of faith that teaching evolution raises, whereas in-service teachers were concerned with their students difficulties in understanding natural selection and mutational randomness. Teacher-training programs that focus on teachers lack of evolution knowledge and on pedagogical skills, as well as the design of teaching materials that take into account these difficulties, are recommended for future research.

The strategic vision proposal for the Programme for International Student Assessment in science for the year 2024, as well as of the Framework for K12 Science Education and the Next Generation Science Standards in the United States, includes the vision that \u201cevery young person should be digitally and data literate.\u201d Thus, engaging in the practice of analyzing and interpreting data is regarded as an essential experience in the teaching and learning of science. For the last two decades, we have been promoting the idea of using authentic databases for the teaching and learning of biology in high school. The use of such databases requires various proficiencies, including the use of computational tools and databases integrated with biological knowledge. Throughout the research, development and implementation that accompanied the promotion of this idea, we have continuously used various frameworks suggested for the examination of knowledge elements that are involved in the teaching and learning of science. In this chapter, we discuss these various theoretical frameworks of scientific knowledge elements and how they have influenced our research and development efforts to promote the teaching and learning of biology using authentic tools and databases.

Biochemistry and molecular biology education starts before our students get to university. From a very early age, they start learning informally about science beginning with the basics of science and as they progress through their school years they should be exposed to more advanced topics such as biochemistry and molecular biology. This session at the conference focused on three very different examples of engaging school students with biochemistry and molecular biology.

The idea of the interaction between genes and environment in the formation of traits is an important component of genetic literacy, because it explains the plastic nature of phenotypes. However, most studies in genetics education characterize challenges in understanding and reasoning about genetic phenomena that do not involve modulation by the environment. Therefore, we do not know enough to inform the development of effective instructional materials that address the influences of environmental factors on genes and traits, that is, phenotypic plasticity. The current study explores college students understanding of phenotypic plasticity. We interviewed biological sciences undergraduates who are at different stages of their undergraduate studies and asked them to explain several phenomena that involved phenotypic plasticity. Analysis of the interviews revealed two types of mechanistic accounts: one type described the interaction as involving the environment directly acting on a passive organism; while the other described the interaction as mediated by a sensing-and-responding mechanism. While both accounts are plausible, the second account is critical for reasoning about phenotypic plasticity. We also found that contextual features of the phenomena may affect the type of account generated. Based on these findings, we recommend focusing instruction on the ways in which organisms sense and respond.

Due to the controversies surrounding the topic of evolution among religious and non-religious people alike, the treatment of biological evolution in educationboth teaching and learningis a potential minefield. The goal of this study was to probe the insights of Israeli stakeholders in education regarding the revision of the Israeli science and technology and biology curricula with respect to evolution. Our study is designed to capture the educational stakeholders opinions regarding the theological tensions surrounding the incorporation of evolution in the curricula, as well as methods of action to overcome or avoid these possible tensions. The study population was composed of 21 educational stakeholders, 11 of them scientists, developers of teaching and learning materials, and current or former chief supervisors at the Israeli Ministry of Education. These stakeholders were interviewed in-depth. The other 10 stakeholders were junior-high-school science or high-school biology leading teachers, for which focus groups were arranged. To obtain the main themes arising from the interviews, thematic analysis was conducted, and codes were obtained by grounded theory analysis. The results show themes of opposition to teaching evolution, a clear voice for no opposition to teaching evolution, and methods of action to overcome or avoid tension at the teacher and student levels. We suggest a culturally competent intervention program to reduce the dissonance between religion and evolution.

Here we present an educational approach that integrates SSI with inquiry-based learning (SSIBL) as a practical and pragmatic approach to promote active citizenship in science education. A model for a teacher professional development course designed to familiarize teachers with SSIBL and to prepare them for implementing this approach in their classrooms is described in the light of two case studies of upper-secondary teachers from Israel who participated in the course. The two case studies point to an advance in both teachers practice as both of them incorporated new practices into their teaching. However, the course enabled the more SSI experienced teacher to advance towards implementing SSIBL, while it enabled the non-SSI experienced teacher to implement SSI, but not to implement SSIBL. In order for SSIBL to become a norm in science classrooms, it should first be legitimized by the school systems. For centralized educational systems, such as the one in Israel, a coherent and focused representation of SSIBL in the national curricula and matriculation exams and the availability of SSIBL focused teaching materials are key factors towards this legitimisation.

The New Horizons in Biochemistry and Molecular Biology Education Conference was organized by the International Union of Biochemistry and Molecular Biology (IUBMB) in collaboration with the Federation of European Biochemical Societies (FEBS), and the Weizmann Institute of Science (Israel) and held in Rehovot, Israel, on September 6-8, 2017. The program covered the entire lifespan of students/scientists from the school level to undergraduate, graduate, and post-doctoral levels and brought together 130 international participants. This article provides an overview of the major issues and topics discussed at the conference and suggestions for the way forward.

The gap between theory and teachers practice is a barrier to education improvement. There is therefore an ongoing need to understand teachers thinking and find new ways to meaningfully relate theory and practice in STEM education. The research explores, through teachers-as-learners questions, the connections made by experienced high-school biology teachers between theory and practice, their practical concerns, and the contribution of a supportive course pedagogy to these connections. The research included 31 experienced high-school biology teachers that participated in a special graduate program.

Mechanisms are central in scientific explanations. However, developing mechanistic explanations is difficult for students especially in domains in which mechanisms involve abstract components and functions, such as genetics. One of the core components of genetic mechanisms are proteins and their functions. Students struggle to reason about the role of proteins while learning genetics and show limited ability to provide mechanistic explanations of genetic phenomena. In genetics education there are currently two competing theoretical frameworks regarding what domain-specific knowledge about proteins is important for reasoning about genetic mechanisms. One framework assumes knowledge about specific protein functions in the body, a tool kit of functions; the other framework assumes more abstracted knowledge about protein interactions that are common to all protein functions. These frameworks implicate different instructional frameworks: One offers to provide concrete examples of protein functions while the other offers a more general description of protein activity. Our aim in this study was to ascertain the ways in which students' reasoning about proteins' role in genetic phenomena (both familiar and novel) relates to the two theoretical frameworks. Toward this end we engaged 7th grade students in learning about proteins functions in the mechanisms underlying genetic traits using an online simulation environment that embodied key aspects of both frameworks. We analyzed students' responses to the final test questions in which they were asked to generatively reason about the underlying mechanisms of two novel genetic traits. Our findings suggest that students use proteins in their explanations mainly when they can explain the protein function and that knowledge about a few specific functions is insufficient to support conceptualization of new functions. Moreover, knowledge of general protein activities common to most functions is also insufficient. We suggest a new combined approach to supporting students' understanding of proteins' role in genetic mechanisms.

Technological breakthroughs in the past two decades have ushered in a new era of biomedical research, turning it into an information-rich and technology-driven science. This scientific revolution, though evident to the research community, remains opaque to nonacademic audiences. Such knowledge gaps are likely to persist without revised strategies for science education and public outreach. To address this challenge, we developed a unique outreach program to actively engage over 100 high-school students in the investigation of multidrug-resistant bacteria. Our program uses robotic automation and interactive web-based tools to bridge geographical distances, scale up the number of participants, and reduce overall cost. Students and teachers demonstrated high engagement and interest throughout the project and valued its unique approach. This educational model can be leveraged to advance the massive open online courses movement that is already transforming science education.

Despite the advancements in the production and accessibility of videos and animations, a gap exists between their potential for science teaching and their actual use in the classroom. The aim of this study was to develop and evaluate an approach to boost chemistry and biology teachers Technological Pedagogical Content Knowledge (TPACK) and their confidence regarding the use of videos and animations in class, which are required for their effective implementation. Twelve experienced high-school chemistry and biology teachers participated in a professional development workshop including biochemistry and technologicalpedagogical lectures along with video-editing instruction and practice. Teachers were provided with digital videos including high-resolution scientifically based animations and were encouraged to edit them based on their pedagogical experience and the needs of their class. We investigated how the workshop affected teachers' TPACK-confidence and TPACK. TPACK-confidence was assessed by pre- and post-workshop questionnaires and open-ended feedback questionnaires. TPACK was assessed by analyses of the edited digital videos and pedagogical considerations submitted by the teachers. It was found that teachers' TPACK-confidence was significantly higher following the workshop. There was also a development in the teachers' TPACK. They were able to recommend to use digital videos in a variety of classroom situations based on the technological pedagogical knowledge (e.g., as an opening to a new topic) and their TPACK (e.g., to visualize complex biochemical processes). We also found a development in their video-editing skills and their knowledge of how to use this technology effectively in biochemistry lessons. Results indicate that training teachers in using technological tools while providing them with relevant Content Knowledge and TPACK, and relying on their pre-existing Pedagogical Content Knowledge may assist them develop their TPACK and TPACK-confidence. This may promote the effective use of videos and animations in biochemistry teaching.

Learning the unique linguistic forms and structures that construct and communicate scientific principles, knowledge, and beliefs is important for developing students' disciplinary literacy. The use of scientific language is apparent in the texts that scientists produce to communicate their findings to other scientiststhe research articles. Texts are underused in the science classroom and the texts that students do read often do not reflect the core attributes of authentic scientific reasoning. Adapted primary literature (APL) refers to an educational genre that enables the use of scientific articles in high school. In the adaptation process, the language of the article is changed to make it more accessible for high school students. Here, we present a systemic functional linguistics (SFL) analysis of an APL article compared to the original research article and to a popular article. The three texts were systematically scanned and compared for specific lexicogrammatical items that characterize five linguistic features of scientific writing: informational density, abstraction, technicality, authoritativeness, and hedging. We found that the adaptation process lowered the lexical complexity, while retaining the authenticity of the scientific writing. APL articles, as suggested by the linguistic analysis presented here, may serve as models of scientific reasoning and communication and may promote students' language awareness and disciplinary literacy. We suggest using APL articles as an apprenticeship genre, for learning about the unique features of authentic scientific texts, and the reasoning that is reflected in the way the articles are written.

Understanding genetic mechanisms affords the ability to provide causal explanations for genetic phenomena. These mechanisms are difficult to teach and learn. It has been shown that students sometimes conceive of genes as traits or as trait-bearing particles. We termed these "nonmechanistic" conceptions of genetic phenomena because they do not allow the space required for a mechanism to exist in the learner's mind. In this study, we investigated how ninth- and 12th-grade students' conceptions of genetic phenomena affect their ability to learn the underlying mechanisms. We found that ninth- and 12th-grade students with nonmechanistic conceptions are less successful at learning the mechanisms leading from gene to trait than students with mechanistic conceptions. Our results suggest that nonmechanistic conceptions of a phenomenon may create a barrier to learning the underlying mechanism. These findings suggest that an initial description of a phenomenon should hint at a mechanism even if the mechanism would be learned only later.

In genetics education, symbols are used for alleles to visualize them and to explain probabilities of progeny and inheritance paradigms. In this study, we identified symbol systems used in genetics textbooks and the justifications provided for changes in the symbol systems. Moreover, we wanted to understand how students justify the use of different symbol systems when solving genetics problems. We analyzed eight textbooks from three different countries worldwide. We then presented a genetics problem to eight 9th-grade students and probed their justifications for the use of different symbol systems. Our findings showed that there is no one conventional symbol system in textbooks; instead, symbol systems are altered along and within textbooks according to the genetic context. More importantly, this alteration is not accompanied by any explicit explanation for the alteration. Student interviews revealed that some students were able to identify the genetic context of each symbol system, whereas others, who were unable to do so, provided justifications based on different non-genetics-related reasons. We discuss the implications of our analysis for how multiple symbol systems should be presented in textbooks, and how they should be introduced in the classroom.

Context-based approaches can bridge the gap between abstract, difficult science concepts and the world students live in. However, the relevance of specific contexts to different groups of learners, and its stability over time, have not been extensively explored. This study used four datasets, collected in different formal and informal settings, to examine which types of contexts could capture the interest of many students and remain so for many years. In the formal setting, responses to closed-ended questionnaires in which 4-12th graders indicated their interest in studying the answers to science questions were compared. Over 700 questionnaires collected in 2007 were compared to over 1600 questionnaires collected in 2016. To document the stability of children's interest in informal science learning settings we compared over 1600 science questions sent to a TV science show in 2004 with over 7000 science questions submitted to a commercial exhibition in 2014. Although there were some differences across ages, students' interest in science remained relatively stable over the 10 years. In the formal setting, this similarity was reflected in the significant linear relationship between the two databases (r=0.917) with regard to the questions students found interesting. In the informal setting, there was a striking similarity in the proportions of spontaneous questions in biology, astrophysics, Earth Science and chemistry. Based on the findings of this study and the literature we recommended, frequently asked questions are a valuable resource for context-based teaching which can serve to identify contexts that enhance the relevance of science in students' lives.

Biology as a discipline has its own language, its own ways of thinking and explaining the natural world and supporting its knowledge claims. However, students and teachers struggle when it comes to reading scientific texts. Helping students to read biology texts requires teachers to promote their students disciplinary literacy by emphasizing appropriate strategies for reading and writing in biology. In many cases, students inability to comprehend the text lies in the texts distinctive structure and language as it is used by biologists to explain the natural world and support their claims. Thus, to help their students cope with the literacy demands of biology, teachers should have a full understanding of the literacy of their discipline, and a better understanding of the central role that language plays in their discipline. Adapted Primary Literature (APL) articles are specifically designed to enable the use of scientific research articles in high school. These articles represent authentically the structure, claims, content and uncertainty that are found in the original research articles and may therefore serve as models of scientific reasoning and communication. In this chapter, we suggest several activities for using APL articles in biology education that are aimed at promoting students disciplinary literacy.

Previous studies have shown that students often ignore molecular mechanisms when describing genetic phenomena. Specifically, students tend to directly link genes to their encoded traits, ignoring the role of proteins as mediators in this process. We tested the ability of 10th grade students to connect genes to traits through proteins, using concept maps and reasoning questions. The context of this study was a computational learning environment developed specifically to foster this ability. This environment presents proteins as the mechanism-mediating genetic phenomena. We found that students' ability to connect genes, proteins, and traits, or to reason using this connection, was initially poor. However, significant improvement was obtained when using the learning environment. Our results suggest that visual representations of proteins' functions in the context of a specific trait contributed to this improvement. One significant aspect of these results is the indication that 10th graders are capable of accurately describing genetic phenomena and their underlying mechanisms, a task that has been shown to raise difficulties, even in higher grades of high school.

To determine what knowledge of genetics is needed for decision-making on genetic-related issues, a consensus-reaching approach was used. An international group of 57 experts, involved in teaching, studying, or developing genetic education and communication or working with genetic applications in medicine, agriculture, or forensics, answered the questions: "What knowledge of genetics is relevant to those individuals not professionally involved in science?" and "Why is this knowledge relevant?" The answers were classified in different knowledge components following the PISA 2015 science framework. During a workshop with the participants, the results were discussed and applied to seven cases in which genetic knowledge is relevant for decision-making. The analysis of these discussions resulted in a revised framework consisting of nine conceptual knowledge components, three sociocultural components, and four epistemic components. The framework can be used in curricular decisions; its open character allows for including new technologies and applications and facilitates comparisons of different cases.

Complications arising from socioscientific issues (SSI) call for immediate and responsible action and warrant students' activism on science-related issues. These issues therefore provide a solid learning context for the advancement of responsible research and innovation (RRI) in science education. This study investigates the development of students' identities as activists as they participate in a high-school project aimed at resolving the problem of global hunger. Drawing from practice-linked identity theory, we present the narratives of two students to examine how they came to embrace the identity of activist. Findings indicate that the students' identities as activists were supported through participation in highly contextual and emotionally charged experiences and through the ability to fill roles that were perceived as integral and authentic to the students. We discuss the potential of a well-structured activity to assist students in deeply engaging with responsible actions.

BackgroundAsking questions is an important scientific practice, and students around the world are expected to learn how to ask their own research questions while performing inquiry. In contrast to authentic scientific inquiry, in most simple inquiry tasks that are carried out in schools, the research questions are given to the students. Here, we characterized the teaching and learning of research-question-asking in the context of an innovative inquiry-oriented program for high-school biotechnology majors, focusing on two case studies of lessons in which students were expected to formulate their research questions.ResultsIn-depth examination of students questions, written during the two lessons, revealed that only in one of the lessons students ability to ask research questions improved. A connection was found between the more student-centered, dialogic, and interactive teaching strategy and the development of students ability to ask research questions in that class. Most of the research questions that were investigated by the students originated from a peer-critique activity during the student-centered lesson, unlike the teacher-focused lesson from which none of the students suggested research questions were selected for investigation.ConclusionsIt can be concluded that a student-centered, dialogic, and interactive teaching strategy may contribute to the development of students ability to ask research questions in an inquiry-oriented high-school program. Encouraging teachers to implement dialogic and interactive classroom discourse in authentic inquiry could be a meaningful tool to support the teaching and learning of scientific abilities such as asking research questions.

Despite the central place held by bioinformatics in modern life sciences and related areas, it has only recently been integrated to a limited extent into high-school teaching and learning programs. Here we describe the assessment of a learning environment entitled 'Bioinformatics in the Service of Biotechnology'. Students' learning outcomes and attitudes toward the bioinformatics learning environment were measured by analyzing their answers to questions embedded within the activities, questionnaires, interviews and observations. Students' difficulties and knowledge acquisition were characterized based on four categories: the required domain-specific knowledge (declarative, procedural, strategic or situational), the scientific field that each question stems from (biology, bioinformatics or their combination), the associated cognitive-process dimension (remember, understand, apply, analyze, evaluate, create) and the type of question (open-ended or multiple choice). Analysis of students' cognitive outcomes revealed learning gains in bioinformatics and related scientific fields, as well as appropriation of the bioinformatics approach as part of the students' scientific 'toolbox'. For students, questions stemming from the 'old world' biology field and requiring declarative or strategic knowledge were harder to deal with. This stands in contrast to their teachers' prediction. Analysis of students' affective outcomes revealed positive attitudes toward bioinformatics and the learning environment, as well as their perception of the teacher's role. Insights from this analysis yielded implications and recommendations for curriculum design, classroom enactment, teacher education and research. For example, we recommend teaching bioinformatics in an integrative and comprehensive manner, through an inquiry process, and linking it to the wider science curriculum.

Several types of knowledge are known to be required for teaching, including content knowledge (CK) and pedagogical content knowledge (PCK). Exploring the relationships between CK and PCK is not a straightforward task due to their complex and tacit nature. Here we aim to expose biology teachers' views about the knowledge required for teaching biology and their tacit views about the relationships between CK and PCK using the repertory grid technique. Data collected from 23 in-service experienced high-school biology teachers revealed that CK is viewed by the participating teachers as an important component of knowledge for teaching. Analysis of their tacit views about the relationships between CK and PCK revealed that CK is viewed by and large as distinct from PCK.

לפי תפיסתו של פולאן, למורים מקום מרכזי במערכת החינוך כ"סוכנים של שינוי" חינוכי וחברתי ]1 .]לשם כך, רצוי שיהיו להם שני מרכיבים חיוניים המשלימים זה את זה: חזון- להציב לעצמם תכלית ויעד חינוכי להביא לשיפור מתמיד בלמידה, תוך שהמורה מודע וקשוב לצרכי התלמידים; כלים ויכולת- פיתוח מיומנויות ואסטרטגיות הנדרשות להגשמת החזון. לדידו נדרשות 4 יכולות ליבה לשם הקניית היכולת לשנות: א) הבניה של חזון אישי, ב) חקירה מתמשכת כמנוע פנימי להתחדשות ולמידה, ג) מומחיות שבסיסה הכשרה איכותית ראשונית שנרכשת לאורך התפתחות הקריירה ומובילה להבנה מעמיקה, ו-ד) שיתוף פעולה. לפיכך, ולאור בסיס הידע והמיומנויות שיש להקנות למורים, הנוגעים להוראה משמעותית ושינוי התנאים המשפיעים על ההוראה, פולאן ועמיתיו בפקולטה לחינוך באוניברסיטת טורונטו גיבשו קריאה לבחינה של תכניות להכשרת מורים. בשנים האחרונות גוברת ההכרה כי למורים תפקיד מפתח באימוץ של רפורמות במערכת החינוך וביישומן. מחקרים מעידים כי ידע בתחום התוכן ומומחיות פדגוגית אינם הכרחיים כשלעצמם לשם יישום מוצלח של רפורמה בתוכנית הלימודים (להלן תה"ל) וכי ישנן סיבות למכביר בגינן מורים אינם מיישמים רפורמות, סיבות הנעוצות במטרות ובהקשרים חיצוניים (תה"ל לדוגמא), פנימיים (בית הספר, חברה), ואישיים (מטרות אישיות, ידע, מיומנויות פדגוגיות). על תכניות להתפתחות מקצועית המלוות רפורמות חינוכיות להכיר, להתחשב ולתת מענה למגוון המטרות של המורים וההקשרים בהם המורים מתפקדים, בכדי לאפשר שינוי אמיתי ויישום של רפורמות. במאמר זה נתאר את השלבים המרכזיים בהתפתחות מקצועית של מורים מובילים כחלק מתהליך ההטמעה של למידה והוראה של ביואינפורמטיקה בתה"ל של המקצוע "מערכות ביוטכנולוגיות". התפתחות מקצועית זו התאפשרה הודות לשיתוף פעולה בין המחלקה להוראת המדעים במכון ויצמן למדע והפיקוח על הוראת ביוטכנולוגיה במשרד החינוך. אחת מגולות הכותרת של ההתפתחות המקצועית הייתה השתלמות מורים ארצית לקראת שנה"ל תשע"ד, שהתקיימה במור-טק, מרכז המורים הארצי למקצועות הטכנולוגיים מדעיים.

This book specifies the foundation for Adapted Primary Literature (APL), a novel text genre that enables the learning and teaching of science using research articles that were adapted to the knowledge level of high-school students. More than 50 years ago, J.J. Schwab suggested that Primary Scientific Articles \u201cafford the most authentic, unretouched specimens of enquiry that we can obtain\u201d and raised for the first time the idea that such articles can be used for \u201cenquiry into enquiry\u201d. This book, the first to be published on this topic, presents the realization of this vision and shows how the reading and writing of scientific articles can be used for inquiry learning and teaching. It provides the origins and theory of APL and examines the concept and its importance. It outlines a detailed description of creating and using APL, and provides examples for the use of the enactment of APL in classes, as well as descriptions of possible future prospects for the implementation of APL. Altogether, the book lays the foundations for the use of this authentic text genre for the learning and teaching of science in secondary schools.

Developing systems thinking skills in school can provide useful tools to deal with a vast amount of medical and health information that may help learners in decision making in their future lives as citizen. Thus, there is a need to develop effective tools that will allow learners to analyze biological systems and organize their knowledge. Here, we examine junior high school students' systems thinking skills in the context of the human circulatory system. A model was formulated for developing teaching and learning materials and for characterizing students' systems thinking skills. Specifically, we asked whether seventh grade students, who studied about the human circulatory system, acquired systems thinking skills, and what are the characteristics of those skills? Concept maps were used to characterize students' systems thinking components and examine possible changes in the students' knowledge structure. These maps were composed by the students before and following the learning process. The study findings indicate a significant improvement in the students' ability to recognize the system components and the processes that occur within the system, as well as the relationships between different levels of organization of the system, following the learning process.Thus, following learning students were able to organize the systems' components and its processes within a framework of relationships, namely the students' systems thinking skills were improved in the course of learning using the teaching and learning materials.

Background: The knowledge that is required for teaching includes subject matter content knowledge (CK) and pedagogical content knowledge (PCK). Although CK and PCK are distinct components of the teachers knowledge, the distinction between those two components and the relationships between them are still underexplored. In a previous study, we showed that biology teachers that participated in a long-term professional development program view CK as an important component of the knowledge required for teaching biology, yet they see it as distinct from PCK. We wondered what are the views of mathematics teachers, who participate in a similar program, on the knowledge that is required for teaching and on the relationships between CK and PCK. In addition, we compared the participating mathematics and biology teachers tacit views of the knowledge required for teaching and on the relationships between CK and PCK.Results: We used the Repertory Grid Technique (RGT) as well as semi-structured interviews and a focus group, to elicit mathematics (n =13) and biology (n =16) teachers tacit views about the knowledge that is required for teaching. The results show that both mathematics and biology teachers view CK as a significant component of their teaching practice. However, whereas mathematics teachers tend to view CK and PCK as related entities, biology teachers tend to view them as separate.Conclusions: The main contribution of this study is in exposing that teachers from different disciplines may view differently the importance of high-level CK to their practice. The differences among the participating mathematics and biology teachers tacit views of the relationships between CK and PCK may aid in the design of professional development programs for mathematics and biology teachers. It is important to draw attention to the ability to recognize the tacit relationships between CK and PCK and to articulate these relationships in planning professional development programs.

Experienced teachers possess a unique teaching knowledge comprised of an inter-related set of knowledge and beliefs that gives direction and justification to a teacher's actions. This study examined the expansion of two components of pedagogical content knowledge (PCK) of three in-service teachers in the course of a professional development program aimed at designing new teaching and learning materials suggested by the teachers themselves. The research presents an enlargement of previous PCK representations by focusing on a detailed representation of two main PCK domains: teaching and learning, including ten PCK components that emerged in the course of data analysis. This representation enabled revealing the unique PCK held by each teacher and to characterize the expansion of the two components of the participating teachers' PCK during the long-term professional development program. Retention of major parts of the expanded PCK a year after termination of the program implies that designing and implementing new teaching and learning materials based on the teachers' experiences, needs, and knowledge in a workshop format accompanied by biology and science education courses might provide a powerful means for PCK expansion. We recommend that designers of professional development programs be aware of the unique PCK held by each teacher in order to promote meaningful professional development of each teacher. Moreover, the PCK representations that were identified in the course of this study enabled clarifying the "orientation toward teaching science" category of PCK which appears to be unclear in current literature.

Bioinformatics is an integral part of modern life sciences. It has revolutionized and redefined how research is carried out and has had an enormous impact on biotechnology, medicine, agriculture and related areas. Yet, it is only rarely integrated into high school teaching and learning programs, playing almost no role in preparing the next generation of information-oriented citizens. Here, we describe the design principles of bioinformatics learning environments, including our own, that are aimed at introducing bioinformatics into senior high school curricula through engaging learners in scientifically authentic inquiry activities. We discuss the bioinformatics-related benefits and challenges that high school teachers and students face in the course of the implementation process, in light of previous studies and our own experience. Based on these lessons, we present a new approach for characterizing the questions embedded in bioinformatics teaching and learning units, based on three criteria: the type of domainspecific knowledge required to answer each question (declarative knowledge, procedural knowledge, strategic knowledge, situational knowledge), the scientific approach from which each question stems (biological, bioinformatics, a combination of the two) and the associated cognitive process dimension (remember, understand, apply, analyze, evaluate, create). We demonstrate the feasibility of this approach using a learning environment, which we developed for the high school level, and suggest some of its implications. This review sheds light on unique and critical characteristics related to broader integration of bioinformatics in secondary education, which are also relevant to the undergraduate level, and especially on curriculum design, development of suitable learning environments and teaching and learning processes.

Inquiry is essentially a process in which research questions are asked and an attempt is made to find the answers. However, the formulation of operational research questions of the sort used in authentic scientific inquiry is not a trivial task. Here, we set out to explore the possible influence of separating the research question from the laboratory techniques used to try and answer this question on teachers' understanding of laboratory techniques and their ability to formulate research questions. We conducted a laboratory course in microbiology in which the laboratory techniques were presented in an explicit and generalized manner, in the context of specific research questions. During the course, teachers' understanding of laboratory techniques improved as reflected in their answers to exercises given throughout. In addition, teachers' ability to ask research questions, analyzed using Dillon's classification of research questions, also improved. When reflecting upon the course, some teachers attributed the change in their ability to ask research questions to their increased knowledge of techniques, whereas others did not. We conclude that to facilitate research-question-asking skills among teachers, they should be provided with knowledge of the relevant laboratory techniques in an explicit fashion.

Animation has great potential for improving the way people learn. A number of studies in different scientific disciplines have shown that instruction involving computer animations can facilitate the understanding of processes at the molecular level. However, using animation alone does not ensure learning. Students sometimes miss essential features when they watch only animations, mainly due to the cognitive load involved. Moreover, students seem to attribute a great deal of authority to the computer and may develop misconceptions by taking animations of abstract concepts too literally. In this study, we attempted to explore teachers' perceptions concerning the use of animations in the classroom while studying biotechnological methods, as well as the teachers' contribution to the enactment of animations in class. Thirty high-school biotechnology teachers participated in a professional development workshop, aimed at investigating how teachers plan for and support learning with animation while studying biotechnological methods in class. From that sample, two teachers agreed to participate in two case studies aimed at characterizing teachers' contribution to the enactment of animations in class while studying biotechnological methods. Our findings reveal marked teacher contribution in the following three aspects: establishing the "hands-on" point of view, helping students deal with the cognitive load that accompanies the use of animation, and implementing constructivist aspects of knowledge construction while studying using animations.

Different genres of scientific articles have begun to diffuse into science curricula. Among them, adapted primary literature (APL) retains the characteristics of scientific research articles, while adapting their contents to the knowledge level of students in the 11th to 12th grades. We present three models for the teaching and learning of the opening sections of an APL article by three different biology teachers. Each of the teachers used a different model for 'stepping into the unknown' of the article. The analysis of the teaching approach of the opening sections of an APL in the classroom illustrates the challenges presented by the use of scientific articles for learning and instruction and the strategies that might be useful in overcoming them. By comparing those models for the APL article, we aim at facilitating the use of different genres of scientific articles in class, and promoting the design of additional teaching/learning models.

Nearly 5,000 self-generated science-related K-12 students' questions, classified into seven science subjects, were used to quantitatively measure the gender gap in science interests and its change with age. In this data set, a difference between boys' and girls' science interests did not exist during early childhood, but increased over 20-fold by the end of high school. Furthermore, the gap widened in a stereotypical manner, with girls being increasingly interested in biology and boys more interested in physics and technology. This method could be applied for identifying and comparing the gender gap in science interests between different populations based on different data sources.

In this study we describe the support provided by a biology teacher during learning using a web-based research simulation that makes use of authentic research practices in genetics, including the use of a heuristic strategy to compare mutated and normal versions of a character at all the organisational levels. Authentic scientific practices include the use of conditional knowledge - namely coordination between declarative and strategic knowledge - which is not typically found in regular school tasks. Thus, it is unlikely that students will be able to carry out such coordination without guidance from their teacher. Our research question was: what kind of support does a teacher provide during enactment of the research simulation and how does it facilitate students' ability to coordinate between declarative and strategic knowledge? We observed one teacher and her students during the enactment of the research simulation in class. Our analysis revealed the support given by a teacher to promote students' use of conditional knowledge in a high-school biology classroom, was similar to the use of such knowledge by scientists in the course of performing authentic research.

This special issue of the Journal of Biological Education is devoted to selected papers from the European Research in the Didactic of Biology (ERIDOB) conference held in Braga, Portugal, in July 2010. The theme of the ERIDOB 2010 conference was Authenticity in biology education: benefits and challenges. This theme emerged from discussions that had taken place at the ERIDOB 2008 conference in Utrecht, The Netherlands. During those discussions, it had become apparent that various ERIDOB members related differently to the meaning of the term authenticity. Some believed that activities that are performed outside the classroom are authentic, while others thought that authentic activities should engage students in posing questions and designing their own paths to solve them. In this short editorial, we attempt to frame authenticity within the current literature, and to point out how the papers that were selected for this special issue contribute to our current understanding of authenticity in biology education.

An identification of students' interests in biology can help teachers better engage their pupils and meet their needs. To this end, over 28,000 self-generated biological questions raised by students from kindergarten through graduate school were analyzed according to age and gender. The sample demonstrated a dominance of female contributions among K-12 students. However, girls' interest in submitting questions dropped as they grew older. Topics popular among different age groups of males and females were identified, and the development of interest was described. Ways in which students' interests can be incorporated into a standard-based curriculum are discussed, mainly as a trigger for the learning of less popular subjects which are required by the curricula.

The most recent science and technology curriculum for junior high school in Israel contains a new guideline stating that the cell topic is to be taught "longitudinally in conjunction with other study contents." This guideline confers a change in teaching the cell topic and provides an opportunity to form meaningful relationships between biological phenomena at the macro level and their cellular explanations. Here, we examined the extent to which six textbooks, available for junior high schools in Israel, support this teaching approach. We found that the textbooks differ in how they express the guideline and that most of them do not support the new teaching approach to any significant extent. Moreover, the textbooks generally emphasize cells' structure and pay less attention to the processes occurring in them. Our findings could shed light on students' difficulties in comprehending the living cell and in correlating macroscopic phenomena with their cellular explanations.

The importance of biotechnology education at the high-school level has been recognized in a number of international curriculum frameworks around the world. One of the most problematic issues in learning biotechnology has been found to be the biotechnological methods involved. Here, we examine the unique contribution of an animation of the polymerase chain reaction (PCR) in promoting conceptual learning of the biotechnological method among 12th-grade biology majors. All of the students learned about the PCR using still images (n = 83) or the animation (n = 90). A significant advantage to the animation treatment was identified following learning. Students' prior content knowledge was found to be an important factor for students who learned PCR using still images, serving as an obstacle to learning the PCR method in the case of low prior knowledge. Through analysing students' discourse, using the framework of the conceptual status analysis, we found that students who learned about PCR using still images faced difficulties in understanding some mechanistic aspects of the method. On the other hand, using the animation gave the students an advantage in understanding those aspects.

Nearly 6,000 science questions collected from five different web-based, TV-based and school-based sources were rigorously analyzed in order to identify profiles of K-12 students' interest in science, and how these profiles change with age. The questions were analyzed according to their topic, thinking level, motivation for and level of autonomy in raising the question, the object of interest and its magnitude, and psychological distance of the object in question from the asker. Characteristics of the asker, such as gender, grade level, and country of origin were also considered, alongside characteristics of the data source, such as language, setting (Internet, school, TV), and the potential science-attentiveness of the users. Six meta-clusters of children's and adolescents' interest in science were identified using cluster analysis of their self-generated science questions. A developmental shift in interest from non-classical to classical school science subjects was noted. Other age-related developments, such as an increase in thinking level as reflected by the questions, a decrease in organization level and the psychological distance of the object in question with age were also explored. Advantages and shortcomings of web-based data collection for educational research are discussed, as are the implications of the results obtained using this methodology for formal science education.

Over the past several decades, there has been a tremendous growth in our understanding of genetic phenomena and the intricate and complicated mechanisms that mediate genetic effects. Given the complexity of content in modern genetics and the inadequacy of current instructional methods and materials it seems that a more coherent and extensive approach to teaching modern genetics is needed. Learning progressions provide such an approach by describing the learning of core concepts in a domain as it unfolds over multiple grades and grade bands. In this paper we suggest a learning progression for modern genetics that spans grades 5 10. We describe the learning progression in terms of three key aspects of teaching and learning modern genetics: (1) the big ideas in modern genetics, and the knowledge and abilities that students should master by the end of compulsory education; and (2) the progression of learning that students are expected to make over several grades; and (3) the identification of learning performances and development of assessments for the proposed progression. We conclude by identifying the implications for instruction and research that stem from our analysis of the research base in genetics education, and our development of a theoretical progression for learning the big ideas in modern genetics.

Adapted primary literature (APL) is a novel text genre that retains the authentic characteristics of primary literature. Learning through APL represents an educational intervention with an authentic scientific context. In this case study, we analyzed the 80-min discourse developed during the enactment of an article from an APL-based curriculum in biotechnology in one class, and examined epistemic practices used by students during their meaning-making of the Results and Discussion sections of the article. Specifically, we examined coordination practices, by which students connected elements belonging to different epistemic status or context (theory, data, experimental stages, biotechnological applications and text). The application of coordination practices was identified more than 70 times during the lesson. In the context of the Results section, the students displayed research-oriented coordination practices, which were frequently associated with claims of comprehension difficulty. In the context of the Discussion section, students displayed text-oriented coordination practices, associated with analysis of the text characteristics. We are suggesting that the research-oriented coordination practices and some of the text-oriented ones enabled the emergence of authentic scientific practices and learning by inquiry. Another type of text-oriented coordination practice enabled reflection on scientists' experimental processes, enabling learning science as inquiry. The enactment model of APL used here allowed for both the emergence of the two dimensions of inquiry learning and the promotion of scientific literacy in the fundamental and derived senses.

Nearly 79.000 questions sent to an Internet-based Ask-A-Scientist site during the last decade were analyzed according to the surfer's age, gender, country of origin, and the year the question was sent. The sample demonstrated a surprising dominance of female contributions among K-12 students (although this dominance did not carry over to the full sample), where offline situations are commonly characterized by males' greater interest in science. This female enthusiasm was observed in different countries, and had no correlation to the level of gender equity in those countries. This suggests that the Internet as a free-choice science-learning environment plays a potentially empowering and democratic role that is especially relevant to populations that are traditionally deprived of equal opportunities in learning formal science. However, worldwide, girls' interest in submitting questions to scientists dropped as they grew older relative to the boys' interest, and the stereotypically gendered science interests persisted in this environment as well. The strengths and limitations of using free-choice Web-based data sources for studying youth interest in science are discussed.

Learning modern genetics is challenging and students have difficulty acquiring a coherent cognitive mental model of abstract concepts such as DNA, bacteria and enzymes. Here we investigated students' mental models of genetics through analysis and interpretation of the discourse that took place while high-school students practised hands-on molecular biology experiments in the laboratory. The lab activity focused on DNA manipulations showing the link between gene and phenotype. The activity was conducted in a unique outreach laboratory setting, entitled Teacher-Led Outreach Laboratories (TLOL). In this setting, the high-school biology teachers themselves teach their students at our institute's laboratories, in contrast to most outreach laboratories in which academic personnel teach visiting classes. Written questionnaires, aimed at probing students' (12^th-graders, n = 181) conceptions, were handed to the students before and immediately following the laboratory activity. The results demonstrated that before the activity, the students have inaccurate mental models which are physical copies of the images they were exposed to during their studies. The students' mental models of DNA and bacteria improved significantly following the activity, as did their procedural understanding of DNA manipulations. Thus, the lab activity in the framework of TLOL promotes high-school students' comprehension of concepts in molecular genetics.

We shall structure this rejoinder around two main sections. In the first, we address three underlying assumptions of our work that Osborne has identified. We indicate points of agreement, disagreement, and clarification. In the second section, we discuss briefly and add our clarifications to three understandings of his that Osborne introduces into the discussion. It should be noted that Osborne's response is grounded in the same basic assumption as our set of papers, namely, the central role played by reading and writing, and communicative activities in general, both in science and in learning science.

In the new science and technology junior-high-school curriculum in Israel, it is recommended that the cell topic be taught 'longitudinally in conjunction with other study contents'. This recommendation confers a change in teaching the cell topic and provides an opportunity to form meaningful relationships between biological phenomena at the macro-level and their cellular explanations. Here, we examine junior-high-school science and technology teachers' pedagogical content knowledge (PCK) with regard to the cell topic and the formation of macro-micro relations, ten years following the publication of the change in the curriculum. Teachers in this study participated in three focus groups (n = 59) and one workshop (n = 12). In addition, six experienced teachers were interviewed in the course of this study. Specific tools were developed to capture the teachers' PCK. We found that the teachers had changed their way of teaching the cell topic only superficially: they did not undergo any deep change. Despite the importance the teachers placed on teaching and learning the cell topic, their concerns about their students' comprehension difficulties reduced the time they devoted to teaching the topic in class. The teachers were also found to have no PCK capacity to integrate biological phenomena at the macro-level with their cellular explanations. In addition, a duality was identified among the teachers with regards to relating macro- and micro-levels in biology and in chemistry.

Providing learners with opportunities to engage in activities similar to those carried out by scientists was addressed in a web-based research simulation in genetics developed for high school biology students. The research simulation enables learners to apply their genetics knowledge while giving them an opportunity to participate in an authentic genetics study using bioinformatics tools. The main purpose of the study outlined here is to examine how learning using this research simulation influences students' understanding of genetics, and how students' approaches to learning using the simulation influence their learning outcomes. Using both quantitative and qualitative procedures, we were able to show that while learning using the simulation students expanded their understanding of the relationships between molecular mechanisms and phenotype, and refined their understanding of certain genetic concepts. Two types of learners, research-oriented and task-oriented, were identified on the basis of the differences in the ways they seized opportunities to recognize the research practices, which in turn influenced their learning outcomes. The research-oriented learners expanded their genetics knowledge more than the task-oriented learners. The learning approach taken by the research-oriented learners enabled them to recognize the epistemology that underlies authentic genetic research, while the task-oriented learners referred to the research simulation as a set of simple procedural tasks. Thus, task-oriented learners should be encouraged by their teachers to cope with the scientists' steps, while learning genetics through the simulation in a class setting.

In her commentary Danielle J. Ford mainly focused on three issues that highlight the promises and challenges for the use of Adapted Primary Literature (APL) in science curricula: the possible contribution of APL to authentic experiences in secondary schools, implementation issues of APL including the support required for the teachers, and the possibilities to extend the use of APL to younger and older students. In this rejoinder, we first offer some general comments on Ford's commentary. Then we offer more specific comments on two areas of her response, authenticity and the support for teachers.

Adapted primary literature (APL) refers to an educational genre specifically designed to enable the use of research articles for learning biology in high school. The present investigation focuses on the paedagogical content knowledge (PCK) of four high-school biology teachers who enacted an APL-based curriculum in biotechnology. Using a constructivist qualitative research approach, we analysed those teachers' aims and beliefs, the instructional strategies they used during the enactment of the curriculum, as well as the outcomes of the enactment as perceived by the teachers and their students, and as reflected in the class observations. Some of the teachers' strategies applied during the enactment, such as the conversational model, were specifically designed for teaching APL-based curricula. We found that the instructional strategies applied for the adapted articles were associated with cognitive and affective engagement, active learning, inquiry thinking, and understanding of the nature of science. Suitable teacher PCK promoted learning by inquiry in addition to learning on inquiry. Students' challenges were mainly linked to the comprehension of complex, multi-stage, biotechnological processes and methods that are abundant throughout the curriculum and required the use of previous knowledge in new contexts. A complex interaction of factors, namely teachers' PCK, the APL genre, and the biotechnology content of the curriculum, shaped the instructional strategies of the new curriculum and the outcomes of its enactment.

Many of the explanations for girls disinterest in physics focus on the role of the educational system in creating this situation. Here, we use evidence from free-choice science learning settings to study if this lack of interest is also expressed in non-school settings. Three sets of self-generated questions raised by children, adolescents and adults in the fields of biology and physics were used. The outcomes of this analysis show that the polar pattern previously described in school science settings, in which physics proves significantly less interesting to girls than to boys, while biology is of greater interest to girls than to boys, also appears in free-choice science learning settings. While boys develop an interest in physics with age, girls do not develop such an interest to the same degree. Thus, the initial gap in interest is probably not based on school-related causes, but its widening in later years probably is. A difference was also found between the genders in the type of information requested and in the motivation for raising the questions. Using topics that appeal to girls interest as the context of science learning could prove beneficial in the process of mainstreaming science education. These topics can be identified using girls spontaneous questions.

Learning to become an interdisciplinary scientist will be needed in order to participate in the scientific research of the future. It is therefore of great importance to learn about the challenges graduate students, with various disciplinary backgrounds, face when carrying out interdisciplinary scientific research. We used the weekly group meetings of an interdisciplinary research group, in the field of systems biology, as a platform to probe the challenges to learning interdisciplinary science. Group meetings were observed and interviews were carried out with the group members. A visible, if sometimes subtle, difference between the challenges facing biologists and those facing physicists was identified. Physicists encountered difficulties in grasping the biological knowledge organization; while biologists found the models suggested by physicists over simplistic. The views of the group members on the nature of the disciplines of physics and biology complement our understanding of the possible causes of some of the identified challenges.

Interest is a powerful motivator; nonetheless, science educators often lack the necessary information to make use of the power of student-specific interests in the reform process of science curricula. This study suggests a novel methodology, which might be helpful in identifying such interests - using children's self-generated questions as an indication of their scientific interests. In this research, children's interests were measured by analyzing 1555 science-related questions submitted to an international Ask-A-Scientist Internet site. The analysis indicated that the popularity of certain topics varies with age and gender. Significant differences were found between children's spontaneous (intrinsically motivated) and school-related (extrinsically motivated) interests. Surprisingly, girls contributed most of the questions to the sample; however, the number of American girls dropped upon entering senior high school. We also found significant differences between girls' and boys' interests, with girls generally preferring biological topics. The two genders kept to their Stereotypic fields of interest, in both their school-related and spontaneous questions. Children's science interests, as inferred from questions to Web sites, could ultimately inform classroom science teaching. This methodology extends the context in which children's interests can be investigated.

Following the rationale that learning is an active process of knowledge construction as well as enculturation into a community of experts, we developed a novel web-based learning environment in bioinformatics for high-school biology majors in Israel. The learning environment enables the learners to actively participate in a guided inquiry process by solving a problem in the context of authentic research in genetics. Through the learning environment, the learners are exposed to a genetics problem which was developed on the basis of research in which a mutated gene, which causes deafness, was identified. They follow, step by step, the way scientists try to solve it, using the current geneticists' toolbox. The environment uses an adapted version of the BLAST program (a bioinformatics tool which enables to find similarities between sequences), which was modified in a way that enables the teachers and students to use it easily. Using quantitative and qualitative research approaches, we were able to show that learning through the bioinformatics environment promotes construction of new knowledge structures and influences students' acquisition of a deeper and multidimensional understanding of the genetics domain. In addition, learning through the bioinformatics environment influences students' comprehension of the practices and scientific ways of thinking.

This article reports the results of an analysis of 1676 science and technology questions submitted by Israeli children to a series of television programmes. It categorizes the children's questions with reference to five different coding schemes: field of interest, motivation for asking the question, type of information requested, country-specific aspects, and source of information. The results point to the popularity of biology, technology, and astrophysics over other sciences, indicate a shift in interests and motivation with age, and reflect a variety of gender-related differences within the sample. The implications of the findings for some current trends in curriculum development and for informal science education are discussed with reference to the wider context of the pupils' voice in education.

Learning using primary literature may be a way of developing a capacity for scientific ways of thinking among students. Since reading research articles is a difficult task for novices, we examined the possible benefits of learning using primary literature versus secondary literature, particularly with respect to their influence on the creation and formation of scientific literacy. We report on a comparison between four groups of high school students, each with differing degrees of prior knowledge in biology, who read a domain-related text written in either the scientific research article genre (adapted primary literature) or the popular-scientific genre (secondary literature). Although there was no significant difference in the students' ability to summarize the main ideas of each text, indicating that there was no eminent distinction in their content, we found that students who read adapted primary literature demonstrated better inquiry skills, whereas secondary literature readers comprehended the text better and demonstrated less negative attitudes toward the reading task. Since the scientific content of the two texts was essentially identical, we suggest that the differences in students' performances stem from the structure of the text, dictated by its genre.

Biology education, like education in any other discipline, strives to make students familiar with the knowledge, activities, and ways of thinking of the community of biologists. We produced a curriculum in developmental biology based on learning through primary literature, in an attempt to develop biological literacy among high-school students. Here we characterize the way in which two high-school biology students read a research article in developmental biology. Mere reading resulted in superficial comprehension. In contrast, when the students answered questions about the text, deeper comprehension evolved. The students could overcome reading-comprehension problems by applying well-established reading strategies, but encountered difficulties resulting from the classical structure of research articles. We hope that our characterization of the learning process of research articles by high-school students will enable the use of these complex texts in high-school biology classrooms.

Question-asking is a basic skill, required for the development of scientific thinking. However, the way in which science lessons are conducted does not usually stimulate question-asking by students. To make students more familiar with the scientific inquiry process, we developed a curriculum in developmental biology based on research papers suitable for high-school students. Since a scientific paper poses a research question, demonstrates the events that led to the answer, and poses new questions, we attempted to examine the effect of studying through research papers on students' ability to pose questions. Students were asked before, during, and after instruction what they found interesting to know about embryonic development. In addition, we monitored students' questions, which were asked orally during the lessons. Questions were scored according to three categories: properties, comparisons, and causal relationships. We found that before learning through research papers, students tend to ask only questions of the properties category. In contrast, students tend to pose questions that reveal a higher level of thinking and uniqueness during or following instruction with research papers. This change was not observed during or following instruction with a textbook. We suggest that learning through research papers may be one way to provide a stimulus for question-asking by high-school students and results in higher thinking levels and uniqueness.

Since biology is one of the most dynamic research fields within the natural sciences, the gap between the accumulated knowledge in biology and the knowledge that is taught in schools, increases rapidly with time. Our long-term objective is to develop means to bridge between the dynamics of biological discoveries and the biology teachers and students. Here we report on our recent initiative towards this objective in which we established a journal club forum as a means towards the professional development of biology teachers. We used the journal club format, which is common within the scientific community, in order to engage biology teachers in a constructivist type of learning in which they acquire new skills and at the same time are continuously updated as to biological discoveries, and can then develop updated activities for their biology students. We suggest using the journal club format for the long-term professional development of biology teachers.

Textbooks, research news from the media, and review articles from popular journals are the most common sources of texts used for high-school biology education. We attempted to adopt primary literature as a means of developing scientific literacy among high-school biology majors. For that purpose, we developed and implemented a primary literature-based curriculum in developmental biology. The process of adapting original research articles to the high-school level, as well as a conversational model developed for learning through research articles, are discussed.

Vinculin is a 117 kDa microfilament-associated protein located at the cytoplasmic aspects of focal contacts and cell-cell adherens type junctions. In both sites, vinculin participates in the formation of a submembrane 'plaque' structure which is responsible for the attachment of actin filaments to the plasma membrane. Vinculin consists of 1066 amino acids, which form a large 90 kDa globular head domain and a rod-like 29 kDa tail domain. The two domains are separated by several stretches of proline residues where the major proteolytic cleavage sites are located. The experimental procedure for isolation and purification of vinculin from smooth muscle has been developed and crystals of native vinculin suitable for X-ray analysis have been obtained. The homogeneity of the vinculin solution was analyzed prior to crystallization using dynamic light scattering. Crystals of vinculin have been obtained in buffer containing 2 mg ml^-1 protein, 0.9 M ammonium sulfate, 0.1 M MES pH 6.5 using both the hanging-drop and sitting-drop vapour-diffusion methods. The crystals have the form of rhombic plates and grow to maximal dimensions of 0.3 x 0.3 x 0.05 mm in two weeks. Preliminary X-ray data show that the crystals diffract to 3.5 Å resolution at the X11 beamline of DESY and belong to the monoclinic space group P2₁. Crystal unit-cell parameters are estimated to be a = 57, b = 351, c: 70 Å, α = 90, β = 113, γ = 90°.

In this study the direct involvement of cadherins in adhesion-mediated growth inhibition was investigated. It is shown here that overexpression of N-cadherin in CHO cells significantly suppresses their growth rate. Interaction of these cells and two additional fibroblastic lines with synthetic beads coated with N-cadherin ligands (recombinant N-cadherin ectodomain or specific antibodies) leads to growth arrest at the G1 phase of the cell cycle. The cadherin-reactive beads inhibit the entry into S phase and the reduction in the levels of cyclin-dependent kinase (cdk) inhibitors p21 and p27, following serum-stimulation of starved cells. In exponentially growing cells these beads induce G1 arrest accompanied by elevation in p27 only. We propose that cadherin-mediated signaling is involved in contact inhibition of growth by inducing cell cycle arrest at the G1 phase and elevation of p27 levels.

The early development of the zebra fish (Danio rerio) embryo is characterized by a series of rapid and synchronous cell cycles with no detectable transcription. This period is followed by the midblastula transition (MBT), during which the cell cycle gradually lengthens, cell synchrony is lost, and zygotic transcription is initially detected. In this work, we examined the changes in the pattern of the cell cycle during MBT in zebra fish and whether these changes are dependent on the initiation of zygotic transcription. To characterize the pattern of the early zebra fish cell cycles, the embryonic DNA content was determined by flow cytometric analysis. We found that G₁ phase is below detection levels during the first 10 cleavages and can be initially detected at the onset of MBT. Inhibition of zygotic transcription, by microinjection of actinomycin D, abolished the appearance of G₁ phase at MBT. Premature activation of zygotic transcription, by microinjection of nonspecific DNA, induced G₁ phase before the onset of MBT, while coinjection of actinomycin D and nonspecific DNA abolished this early appearance of G₁ phase. We therefore suggest that during the early development of the zebra fish embryo, G₁ phase appears at the onset of MBT and that the activation of transcription at MBT is essential and sufficient for the G₁-phase induction.

Cyclin E cDNA, cloned from a zebrafish embryonic cDNA library, was used for analysis of cyclin E regulation during early embryogenesis. During the rapid cell cycles of the early cleavage stage, which lacks a G1 phase, the cyclin E mRNA, protein, and associated H1 kinase activity were found to be constitutive, in contrast to their reported cyclic behavior during the cycle of cultured mammalian cells. These results suggest an additional role for cyclin E during early embryogenesis, in addition to its established role during the G1/S transition in somatic cells. These results support previous identification of cyclin E in early cleaving Drosophila and Xenopus embryos, and provide for the first time the direct demonstration of constitutive cyclin E activity throughout the M/S cycles of the embryonic cleavage stage. Cyclin E mRNA was reduced during epiboly (approximately 6-8 hr postfertilization, HPF), concomitantly with a marked reduction in cell division rates. In contrast, the cyclin E protein and cyclin E-CDK complexes remained constant throughout the first 24 hr, implying that the cyclin E protein is regulated post translationally and is not immediately affected by the levels of the corresponding mRNA. However, the cyclin E-CDK complexes present in 26 somite embryos (22 HPF) did not exhibit histone H1 kinase activity. This discrepancy between high levels of cyclin E-CDK complexes and low enzymatic activity may be explained by the presence of putative cyclin E- CDK inhibitory mechanism. Here we show that multiple levels of regulation of the cyclin E mRNA, protein, and associated kinase activity are present during the first 24 hr of zebrafish embryonic development.

Cultured epithelial cells interact massively, rapidly and stereospecifically with the {011} faces of calcium (R,R)-tartrate tetrahydrate crystals. It was suggested that the massive rapid adhesion represents an exaggerated and isolated form of the first initial events in the attachment of cultured cells to conventional tissue culture surfaces (Hanein, et al., Cells and Materials, 5, 197-210; 1995). Attachment is however not followed by normal cell spreading and development of focal adhesions, but results in massive cell death. In this study, the fate of the crystal-bound cells was characterized by electron microscopy, flow cytometry and microscopic morphometry and was found to display the characteristics of physiological cell death. We show that the direct interaction with the highly homogenous and repetitive {011} faces per se does not trigger the transduction of lethal transmembrane signals. We suggest that the excessive direct interactions between the cell membrane and the crystal, by impairing cell motion, prevent the evolution of RGD-dependent cell adhesion. This implies that the deprivation of proper extracellular matrix (ECM)-receptor contacts of substrate-attached epithelial cells eventually triggers physiological cell death.Errata available

We have isolated and determined the nucleotide sequence of a cDNA containing the complete coding region of cyclin D1 from embryonic zebrafish cDNA library. The cyclin D1 gene is a single copy gene within the zebrafish genome, which undergoes an alternative polyadenylation process. The initial expression of cyclin Dl transcript occurs at the presumed onset of G1 phase in the developing zebrafish embryo.

EXPRESSION OF G1 CYCLINS DURING EARLY DEVELOPMENT OF ZEBRAFISH EMBRYOS

Transcription factor E2F binds to cellular promoters of certain growth- and cell cycle-controlling genes and forms distinct heteromeric complexes with other nuclear proteins. We show here that alpha and beta interferons (α, β) and interleukin-6 abolished the E2F-containing DNA-binding complexes in Daudi Burkitt lymphoma cells and in M1 myeloblastic cells, which responded to the cytokines by suppression of c-myc transcription. Time kinetics studies showed that the abolishment of E2F complexes coincided with reduction of c-myc expression and that both molecular events preceded the cell cycle block in G₀/G₁ phase. In contrast, the pattern of E2F complexes remained unchanged in an interferon-treated growth-resistant Daudi cell mutant that displayed relaxed regulation of c-myc. All of the DNA-binding E2F complexes, including those containing the retinoblastoma protein (pRB), cyclin A-p33^cdk2, and the free forms of E2F, were reduced by interferons or interleukin-6. Their abolishment was unperturbed by pharmacological treatments that alleviated the cyclin A and pRB responses to interferon. Thus, changes in cyclin A expression and pRB phosphorylation are not primary events that influence the pattern of E2F responses to cytokines. Addition of EDTA to cell extracts of interferon-treated Daudi cells restored the DNA-binding activity of E2F, resulting in the appearance of a single E2F complex that exclusively contained pRB. It is suggested that the regulation of E2F by growth-inhibitory cytokines that induce cell cycle exit takes place at the level of the DNA-binding activity, and by that mean it differs basically from the phase-specific regulation of E2F in cycling cells.

Keywords: Biochemistry & Molecular Biology; Oncology; Pharmacology & Pharmacy

Different hematopoietic cells produce minute amounts of β-related interferon (IFN) following induction of differentiation by chemical or natural inducers. The endogenous IFN binds to type I cell surface receptors and modulates gene expression in the producer ceils. We show that self-induction of two members of the IFN-induced gene family differs in the dose response sensitivity and the prolonged kinetics of mRNA accumulation from the response to exogenous IFN-β₁. Production and response to endogenous IFN are also detected when bone marrow precursor cells differentiate to macrophages after exposure to colony stimulating factor 1. In M1 myeloid cells induced to differentiate by lung-conditioned medium, addition of antibodies against IFN-β partially abrogates the reduction of c-myc mRNA and the loss in cell proliferative activity, which both occur during differentiation. The endogenous IFN therefore functions as an autocrine growth inhibitor that participates in controlling c-myc suppression and the specific G0 G1 arrest during terminal differentiation of hematopoietic cells.

The suppression of the c-myc nuclear oncogene is associated with growth arrest and may therefore be directly controlled by naturally occurring growth inhibitors. The effect of tumor necrosis factor (TNF) and of interferon-γ (IFN-γ) on c-myc expression was investigated in HeLa cells, which respond to these cytokines by a specific arrest in the G₀/G₁ phase of the cell cycle. Northern blot and nuclear transcription analyses indicated that each cytokine reduced within 1 to 3 hours the c-myc messenger RNA levels as a result of transcriptional inhibition. Adding the two cytokines together at saturating levels resulted in enhanced inhibition of c-myc transcription and of the c-myc messenger RNA steady-state levels. While the reduction of c-myc messenger RNA by IFN-γ was dependent on new protein synthesis, the inhibitory effect of TNF on c-myc messenger RNA was direct and was not abrogated by cycloheximide. The differential effect of the protein synthesis inhibitor and the cooperative inhibitory effects of the two cytokines when added together suggest that IFN-γ and TNF reduce c-myc transcription through different molecular mechanisms.

The expression of class I HLA genes was measured during the in vitro differentiation of human U937 lymphoma cells towards macrophages. Following the onset of differentiation by phorbol myristate acetate the levels of cytoplasmic mRNA that hybridized with a [32P]HLAB cDNA probe increased by a factor of nine. Elevation in HLA mRNA accumulation was followed by an increase in the rate of synthesis of HLA proteins and also by a dramatic increase in class I HLA cell surface antigen expression, as shown by cytofluorimetric analysis. The elevation in HLA mRNA and surface antigens could be prevented by adding antibodies against human interferonbeta (IFNbeta) to the culture medium at the onset of differentiation. Interferon antiviral activity was detected in the medium of differentiated U937 cells. The same antiIFNbeta antibodies prevented the increase in (25)oligo(A) synthetase activity which also takes place in differentiating U937 cells. Accumulation of the IFNinduced (25)oligo(A) synthetase in U937 cells is preceded by an increase in its specific 1.6kb mRNA as shown by hybridization to cloned (25)oligo(A) synthetase cDNA. The enzyme was preferentially found in the nuclear fraction of differentiating U937 cells. We suggest that an autogenous production of interferonbeta by the differentiating cells, switches on expression of the class I HLA genes as well as that of the (25)oligo(A) synthetase.