This volume details a wide range of methods, ranging from beginner through advanced, used to further study zebrafish and fish germline. Chapter guide readers through cultivating and manipulating germ cells, imaging of germline processes and the molecular analysis of their, protein, and RNA. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, application details for both the expert and non-expert reader, and tips on troubleshooting and avoiding known pitfalls. Authoritative and cutting-edge, Germline Development in the Zebrafish: Methods and Protocols aims to ensure successful results in the further study of this vital field.
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
Infertility affects more than one in ten couples worldwide and is related to highly heterogeneous pathologies sometimes only discernible in the germ line. Its complex etiology often, but not always, includes genetic factors besides anatomical defects, immunological interference, and environmental aspects. Nearly 30% of infertility cases are probably caused only by genetic defects. Thereby experimental animal knockout models convincingly show that infertility can be caused by single or multiple gene defects. Translating those basic research findings into clinical studies is challenging, leaving genetic causes for the vast majority of infertility patients unexplained. Nevertheless, a large number of candidate genes have been revealed by sophisticated molecular methods. This book provides a comprehensive overview on the subject of infertility written by the leading authorities in this field. It covers topics including basic biological, cytological, and molecular studies, as well as common and uncommon syndromes. It is a must-read for human geneticists, endocrinologists, epidemiologists, zoologists, and counsellors in human genetics, infertility, and assisted reproduction.
In this comprehensive and cutting-edge book, leading experts explore the parameters that define germline stem cells and the mechanisms that regulate the cell behavior in order to better isolate, characterize and maintain them. The volume begins by providing protocols for germline stem cell identification and regulation in model organisms, and concludes with detailed chapters covering current techniques involving in vitro culture and the applications of the cells.
Connects classical cellular descriptive studies with more recent work on the molecular and genetic aspects regarding germline development. Prominent scientists discuss research on a range of organisms including insects, worms, birds, fish, amphibia, mammals and green algae. Specification of germ cells, their migration to the gonads and subsequent interactions with the soma and evolutionary factors of their segregation are among the topics covered.
Scientists investigating germ cells have, over the past 15 years, originated discoveries and innovations that give us valuable insights into the mechanisms that regulate not just stem cell function, but human development in its widest sense. With contributions from some of the leading researchers in the field, Male Germline Stem Cells: Developmental and Regenerative Potential assesses the implications of these discoveries for understanding the fundamental biology of germline stem cells as well as their potential for human stem cell-based therapies. This monograph covers many of the fundamental issues now being explored by today’s generation of stem cell researchers, including the field’s potential for regenerative medicine. Ranging from an assessment of the pluripotency of primordial germ cells and their possible applications in treating testicular cancer, to the recovery of once-mordant fertilization-competent sperm, this volume has it all. It is a reference point for any scientist involved in related research as well as being a timely summation of what could prove to be a hugely exciting and very fruitful area of inquiry.
Heritable human genome editing - making changes to the genetic material of eggs, sperm, or any cells that lead to their development, including the cells of early embryos, and establishing a pregnancy - raises not only scientific and medical considerations but also a host of ethical, moral, and societal issues. Human embryos whose genomes have been edited should not be used to create a pregnancy until it is established that precise genomic changes can be made reliably and without introducing undesired changes - criteria that have not yet been met, says Heritable Human Genome Editing. From an international commission of the U.S. National Academy of Medicine, U.S. National Academy of Sciences, and the U.K.'s Royal Society, the report considers potential benefits, harms, and uncertainties associated with genome editing technologies and defines a translational pathway from rigorous preclinical research to initial clinical uses, should a country decide to permit such uses. The report specifies stringent preclinical and clinical requirements for establishing safety and efficacy, and for undertaking long-term monitoring of outcomes. Extensive national and international dialogue is needed before any country decides whether to permit clinical use of this technology, according to the report, which identifies essential elements of national and international scientific governance and oversight.
This book is about the development of the animal embryo starting from the fertilised egg. The emphasis is on the problem of pattern formation: how cells in different regions of the embryo become programmed to form the various structures of the body in the correct relative positions.
Genome editing is a powerful new tool for making precise alterations to an organism's genetic material. Recent scientific advances have made genome editing more efficient, precise, and flexible than ever before. These advances have spurred an explosion of interest from around the globe in the possible ways in which genome editing can improve human health. The speed at which these technologies are being developed and applied has led many policymakers and stakeholders to express concern about whether appropriate systems are in place to govern these technologies and how and when the public should be engaged in these decisions. Human Genome Editing considers important questions about the human application of genome editing including: balancing potential benefits with unintended risks, governing the use of genome editing, incorporating societal values into clinical applications and policy decisions, and respecting the inevitable differences across nations and cultures that will shape how and whether to use these new technologies. This report proposes criteria for heritable germline editing, provides conclusions on the crucial need for public education and engagement, and presents 7 general principles for the governance of human genome editing.
