Determinants of Neuronal Identity

Determinants of Neuronal Identity brings together studies of a wide range of vertebrate and invertebrate organisms that highlight the determinants of neuronal identity. Emphasis of this book is on how neurons are generated; how their developmental identities are specified; and to what degree those identities can be subsequently modified to meet the changing needs of the organism. This book also considers various techniques used in the analysis of different organisms.
This volume is comprised of 15 chapters; the first of which introduces the reader to the specification of neuronal identity in Caenorhabditis elegans. The discussion then turns to neurogenesis and segmental homology in the leech, as well as intrinsic and extrinsic factors influencing the development of Retzius neurons in the leech nervous system. Drosophila is discussed next, with particular reference to neuronal diversity in the embryonic central nervous system, cell choice and patterning in the retina, and development of the peripheral nervous system. Other chapters explore endocrine influences on the postembryonic fates of neurons during insect metamorphosis; neuron determination in the nervous system of Hydra and in the mammalian cerebral cortex; and segregation of cell lineage in the vertebrate neural crest.
This book will help scientists and active researchers in synthesizing a conceptual framework for further studies of neuronal specification.

Contenu

Contributors
Preface
1 Specification of Neuronal Identity in Caenorhabditis elegans
I. Introduction
II. Early Neurogenesis
III. Cell Type Specification and Differentiation (Late Neurogenesis)
IV. Prospects
References
2 Segmental Differentiation of Lineally Homologous Neurons in the Central Nervous System of the Leech
I. Introduction
II. Leech Neuroanatomy
III. Neurogenesis and Segmental Homology
IV. Determination of Neuronal Phenotype by Cell Lineage History
V. Determination of Neuronal Phenotype by Postmitotic Cell Interactions
VI. Spatial Patterning of Neuronal Differentiation
References
3 Control of Central Neurogenesis in the Leech
I. Introduction
II. Early Neurogenesis in the Leech
III. Significant Segmental Differences in Cell Number in the Ventral Nerve Cord
IV. Birth of Extra Neurons in the Sex Ganglia Depends on Their Innervation of the Male Genitalia
V. What are the Precursors of the Peripherally Induced Central Neurons?
VI. What is the Nature of the Mitogenic Signal?
References
4 Intrinsic and Extrinsic Factors Influencing the Development of Retzius Neurons in the Leech Nervous System
I. Introduction
II. Adult Properties of Retzius Neurons
III. Influences of Intrinsic Properties and Early Interactions
IV. Later Peripheral Interactions
V. Summary
References
5 The Generation of Neuronal Diversity in the Drosophila Embryonic Central Nervous System
I. Neuroblast Formation
II. Generation of Neuronal Diversity
III. Gene Regulatory Hierarchies in the Central Nervous System
IV. Perspectives
References
6 Initial Determination of the Neuroectoderm in Drosophila
I. Introduction
II. The Neural-Epidermal Decision
III. Genetic Mechanisms in the Neural-Epidermal Decision: Controlling Gene Expression
IV. Genetic Mechanisms in the Neural-Epidermal Decision: Genes Taking Part in Interactions between Cells
V. The Neural-Epidermal Decision: Tilting the Balance and Keeping it Tilted
VI. Conclusion
References
7 Cell Choice and Patterning in the Drosophila Retina
I. Introduction
II. Structure of the Compound Eye
III. Description of Eye Development
IV. Developmental Analysis of the Retina
V. The Role of Specific Genes in Regulating Eye Development
VI. Perspective
References
8 Development of the Peripheral Nervous System in Drosophila
I. Introduction
II. A Progressive Process
III. Acquisition of Competence
IV. Singling out the Sensory Mother Cell
V. Differentiating the Sensory Mother Cell
VI. Differentiating the Neuron
VII. Programming Diversity
Appendix: Genetic Methods and Tools
References
9 Endocrine Influences on the Postembryonic Fates of Identified Neurons During Insect Metamorphosis
I. Introduction
II. Description of the Life Cycle and Hormones of Manduca
III. Metamorphic Fates of Identified Neurons
IV. Conclusions
References
10 Neuron Determination in the Ever-Changing Nervous System of Hydra
I. Introduction
II. The Nervous System of Hydra
III. The Nerve Net is Dynamic
IV. Neuron Cell Lineages
V. Commitment of Multipotent Stem Cells to Neuronal Differentiation
VI. Neuronal Phenotype is Position-Dependent
VII. Basis of Position-Dependent Conversion
VIII. Summary
References
11 Cell Lineage Segregation in the Vertebrate Neural Crest
I. Introduction
II. Developmental Potential of Neural Crest Cell Populations
III. Evidence That Individual Neural Crest Cells are Multipotent
IV. Evidence for Subpopulations at Stages of Neural Crest Cell Migration
V. Evidence for Neural Crest Sublineages at Postmigratory Stages
VI. Role of Growth Factors in Neural Crest Cell Differentiation
VII. Phenotypic Plasticity in Neural-Crest-Derived Ganglia
VIII. Conclusions Regarding Mechanism s of Cell-Type Segregation in the Neural Crest
References
12 The Determination of Neuronal Identity in the Mammalian Cerebral Cortex
I. Introduction
II. Organization and Development of the Mammalian Cerebral Cortex
III. Mechanisms of Neuronal Determination
IV. Axon Outgrowth in the Developing Cerebral Cortex
V. Summary
References
13 Generation of Neuronal Diversity in the Vertebrate Retina
I. Introduction
II. The Embryology of the Eye
III. Sensory Retinal Histogenesis
IV. Mechanisms of Cell Determination in the Sensory Retina
V. Conclusions
References
14 Development of Motoneuronal Identity in the Zebrafish
I. Introduction
II. Early Patterning of the Embryo
III. Differentiation of the Nervous System
IV. Criteria for Identification of Primary Motoneurons
V. Development of Primary Motoneuronal Identity
VI. Conclusions
References
15 Cellular and Molecular Mechanisms Determining Neurotransmitter Phenotypes in Sympathetic Neurons
I. Introduction
II. Neurotransmitter Phenotypes of Sympathetic Neurons
III. A System for Studying Cholinergic Sympathetic Neurons: Sweat Gland Innervation
IV. Developmental History of Sympathetic Neurons
V. Molecules That Specify Neurotransmitter Phenotype
VI. Transient Catecholaminergic Cells of the Gut also Change Their Phenotype
VII. Effects of the Alteration in Transmitter Properties on Target Function
VIII. Summary and Conclusions
References
Index