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

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.

"A subject collection from Cold Spring Harbor perspectives in biology."

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.

This book describes human development including sexual reproduction and stem cell research with the development of model organisms that are accessible to genetic and experimental analysis in readily understandable texts and 315 multi-colored graphics. The introductory account of model organisms selected from the entire animal kingdom presents general principles, which are then outlined in subsequent chapters devoted to, for example, sexual development; genes controlling development and their contemporary molecular-analysis methods; production of clones and transgenic animals; development of the nervous and circulatory systems; regenerative medicine and ageing. Finally the evolution of developmental toolkits and novelties is discussed including the genetic basis of the enlargement of the human forebrain. Separate boxes are devoted to controversial questions such as the benefits and problems of prenatal diagnostics or the construction of ancient body plans.

Authored by leading experts in the field, this book provides the first comprehensive overview of the mechanisms of early patterning and morphogenesis in zebrafish. It summarizes the current knowledge and the key questions for the next decade of research.

Biology and Evolution of the Mexican Cavefish features contributions by leading researchers in a comprehensive, unique work that examines a number of distinct areas of biology—evolution, development, ecology, and behavior—using the Mexican cavefish as a powerful model system to further understanding of basic biological processes such as eye degeneration, hearing, craniofacial development, sleep, and metabolic function. These fish are currently being used to better understand a number of issues related to human health, including age-related blindness, sleep, obesity, mood-related disorders, and aging. The recent sequencing of the cavefish genome broadens the interest of this system to groups working with diverse biological systems, and has helped researchers identify genes that regulate sleep, eye degeneration, and metabolic function. Mexican cavefish are particularly powerful for the study of biological processes because these fish evolved independently in twenty-nine caves in the Sierra de el Abra Region of Northeast Mexico. These fish have dramatic adaptations to the cave environment, and this can be used to identify genes involved in disease-related traits. This scholarly text will be of interest to researchers and students throughout diverse areas of biology and ecology. It includes photographs of animals and behavior in laboratory and natural settings that will also increase interest and accessibility to non-experts. - Includes a mixture of images and illustrations such as the geographical distribution of cave pools and the developmental biology of the nervous system - Features a companion site with geographical maps - Fills a notable gap in the literature on a topic of broad interest to the scientific community - Presents the recent sequencing of the cavefish genome as a groundbreaking development for researchers working with diverse biological systems