The genetic development of eggs in fruit fly (Drosophilia) is the most important model used by developmental biologists in understanding how we go from a fertilized egg to a fully developed organism. Insights into fruit fly genetics have also begun to provide an idea as to how humans develop. This text amasses and organizes information on nearly 400 genes affecting the origin and development of ova. It should aid understanding of the crucial processes in organisms development.

This volume provides current up-to-date protocols for preparing the ovary for various imaging techniques, genetic protocols for generating mutant clones, mosaic analysis and assessing cell death. Chapters address methods for performing genome wide gene expression analysis and bioinformatics for studies of RNA-protein interactions. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and cutting-edge, Drosophila Oogenesis: Methods and Protocols aims to ensure successful results in the further study of this vital field.

This book will give an overview of insect ovaries, showing the diversities and the common traits in egg growth processes. The idea to write this book developed while looking at the flood of information which appeared in the early 1980s on early pattern formation in Drosophila embryos. At this time a significant breakthrough was made in studies of this little fly, combining molecular biological methods with classical and molecular genetics. The answers to questions about early pattern formation raised new questions about the architecture of ovaries and the growth of eggs within these ovaries. However, by concentrating only on Drosophila it is not possible to form an adequate picture of what is going on in insect ovaries, since the enormous diversity found among insects is not considered sufficiently. Almost forgotten, but the first to study the architecture of ovaries, was Alexander Brandt writing in 1878 in aber das Ei und seine Bildungsstaette (On the egg and its organ of development). More than 100 years later, a series of ten books or more would be required to survey all the serious informa tion we have today on insect oogenesis. Thus, this book is a personal selection and personal view on the theme, and the authors must be excused by all those scientists whose papers could not be included. The book briefly describes the ectodemes, i. e.

Eggs of all animals contain mRNAs and proteins that are supplied to or deposited in the egg as it develops during oogenesis. These maternal gene products regulate all aspects of oocyte development, and an embryo fully relies on these maternal gene products for all aspects of its early development, including fertilization, transitions between meiotic and mitotic cell cycles, and activation of its own genome. Given the diverse processes required to produce a developmentally competent egg and embryo, it is not surprising that maternal gene products are not only essential for normal embryonic development but also for fertility. This review provides an overview of fundamental aspects of oocyte and early embryonic development and the interference and genetic approaches that have provided access to maternally regulated aspects of vertebrate development. Some of the pathways and molecules highlighted in this review, in particular, Bmps, Wnts, small GTPases, cytoskeletal components, and cell cycle regulators, are well known and are essential regulators of multiple aspects of animal development, including oogenesis, early embryogenesis, organogenesis, and reproductive fitness of the adult animal. Specific examples of developmental processes under maternal control and the essential proteins will be explored in each chapter, and where known conserved aspects or divergent roles for these maternal regulators of early vertebrate development will be discussed throughout this review. Table of Contents: Introduction / Oogenesis: From Germline Stem Cells to Germline Cysts / Oocyte Polarity and the Embryonic Axes: The Balbiani Body, an Ancient Oocyte Asymmetry / Preparing Developmentally Competent Eggs / Egg Activation / Blocking Polyspermy / Cleavage/ Mitosis: Going Multicellular / Maternal-Zygotic Transition / Reprogramming: Epigenetic Modifications and Zygotic Genome Activation / Dorsal-Ventral Axis Formation before Zygotic Genome Activation in Zebrafish and Frogs / Maternal TGF-β and the Dorsal-Ventral Embryonic Axis / Maternal Control After Zygotic Genome Activation / Compensation by Stable Maternal Proteins / Maternal Contributions to Germline Establishment or Maintenance / Perspective / Acknowledgments / References

There is no multicellular animal whose genetics is so well understood as Drosophila melanogaster. An increasing number of biologists have, therefore, turned to the fruitfly in pursuit of such diverse areas as the molecular biology of eukaryotic cells, development and neurobiology. Indeed there are signs that Dro sophila may soon become the most central organism in biqlogy for genetic analysis of complex problems. The papers in this collection were presented at a conference on Development and Behavior of Drosophila held at the Tata Insti tute of Fundamental Research from 19th to 22nd December, 1979. The volume reflects the commonly shared belief of the participants that Drosophila has as much to contribute to biology in the future as it has in the past. We hope it will be of interest not merely to Dro sophilists but to all biologists. We thank Chetan Premani, Anil Gupta, K.S. Krishnan, Veronica Rodrigues, Hemant Chikermane and K. Vijay Raghavan for help with recording and transcription of the proceedings and Vrinda Nabar and K.V. Hareesh for editorial assistance. We thank Samuel Richman, Thomas Schmidt-Glenewinkel and T.R. Venkatesh for their valuable assistance in proofreading the manuscripts, and we also thank Patricia Rank for her excellent effort in the preparation of the final manuscripts. The conference was supported by a grant from Sir Dorabji Tata Trust.

Scientific Frontiers in Developmental Toxicology and Risk Assessment reviews advances made during the last 10-15 years in fields such as developmental biology, molecular biology, and genetics. It describes a novel approach for how these advances might be used in combination with existing methodologies to further the understanding of mechanisms of developmental toxicity, to improve the assessment of chemicals for their ability to cause developmental toxicity, and to improve risk assessment for developmental defects. For example, based on the recent advances, even the smallest, simplest laboratory animals such as the fruit fly, roundworm, and zebrafish might be able to serve as developmental toxicological models for human biological systems. Use of such organisms might allow for rapid and inexpensive testing of large numbers of chemicals for their potential to cause developmental toxicity; presently, there are little or no developmental toxicity data available for the majority of natural and manufactured chemicals in use. This new approach to developmental toxicology and risk assessment will require simultaneous research on several fronts by experts from multiple scientific disciplines, including developmental toxicologists, developmental biologists, geneticists, epidemiologists, and biostatisticians.