What makes an ideal model system to study embryonic development? The answer to this question has varied in the course of scientific quest, depending on the available experimental approaches. Yet, at the beginning of the new millennium, most of the mainstream model organisms have one feature in common, they are amenable to genetic analysis. Indeed, the genetic approach has proven remarkably effective in the dissection of complex biological phenomena, starting with the regulation of the lactose operon in Escherichia coli, the decision between the lysogenic and lytic cycles of the lambda phage and the yeast cell cycle control. The genetic screens for mutations affecting embryonic development of a fruit fly, Drosophila melanogaster, carried out by Christiane Niisslein-Volhard, Eric Wieschaus and Edward Lewis, marked the turning point in experimental approaches to embryonic development of more complex organisms. The resulting mutants facilitated identification of the key regulatory molecules, while their phenotypic classes hinted at the underlying regulatory mechanisms. This work not only provided a paradigm for genetic dissection of other developmental processes, but also inspired many budding embryologists throughout the world. Soon thereafter, George Streisinger noted that, among vertebrates, the zebrafish, Danio rerio, offered many features facilitating the dissection of nervous system development and function. Among these, transparency of the embryo, ease of husbandry, and the highly prolific nature make the zebrafish a good genetic model system.

I. Germ Layer Formation and Early Patterning

Formation and Patterning Roles of the Yolk Syncytial Layer
Mesoderm Induction and Patterning
The Guts of Endoderm Formation
Organizer Formation and Function
Dorsoventral Patterning in the Zebrafish: Bone Morphogenetic Proteins and Beyond
Specification of Left-Right Asymmetry
II. Gastrulation Movements
Life at the Edge: Epiboly and Involution in the Zebrafish
Cellular and Genetic Mechanisms of Convergence and Extension
Primordial Germ Cell Development in Zebrafish
III. Neural Development
Patterning the Zebrafish Central Nervous System
Specification of the Zebrafish Neural Crest
Neurogenesis and Specification of Neuronal Identity
Cellular, Genetic and Molecular Mechanisms of Axon Guidance in the Zebrafish
IV. Aspects of Organogenesis
Somitogenesis
Cardiovascular System
The Pronephros
The Zebrafish Eye: Developmental and Genetic Analysis
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