The Fish Oocyte

This book presents a comprehensive overview on egg production in fish, from the standpoint of the oocyte. It covers oocyte development, maturation, hydration and fertilization. The book places special emphasis on using state-of-the-art tools for discerning the ultra-structure of the follicle and genomic/proteomic tools to fully understand biological basis of fish reproduction.

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

With the decline in world fish stocks, our knowledge of fish reproduction has become fundamental. Reproduction is an essential commitment to future generation. It is also a continuous development process throughout ontogeny, requiring energetic, ecological, physiological, anatomical, biochemical and endrocrinological adaptations. The first chapters highlight important issues affecting fish normal ways of reproductive development; details would focus on species living in opposite environments, such as tropical and polar fishes; far related, as teleosts and cartilaginous fishes; and finally, fish having different reproductive strategies. Thereafter, since many fishes live in detrimental environments, mainly induced by the continuous input of xenobiotic substances into waterways, the authors found it highly pertinent to include this topic. Herein, the authors fix their attention on the factors and mechanisms that may well affect reproductionrelated hormonal systems as also on known consequences for fish living i

This volume describes the myriad ways in which fish have approached problems of reproduction — it is an amply illustrated comparative study of the microscopic structure of the female genital systems of fish. The timing of its appearance is auspicious in that it coincides with the decline of the golden age of descriptive morphology. It is a compilation of thousands of micrographs from classic works in the field. The volume should prove valuable to investigators studying fish in areas such as ecology, physiology, and reproductive biology who may view histology as essential in their work but have little background in this area.

In the compiling of this book, the vast literature dealing with the descriptive morphology, histology and cytology of teleost development has been combed and integrated. The book is divided into 21 chapters, starting with the egg and embryonic development up to hatching. This is followed by a description of ectodermal, mesodermal and entodermal derivatives and the development of various organs. The subject index, species index and the abundant illustrations add extra value to this long awaited book. Developmental Biology of Teleost Fishes will be a valuable tool for scientists and students in the fields of biology, developmental biology, molecular biology and fish biology.