[Frontiers in Bioscience 9, 85-92, January 1, 2004]

EGF FAMILY OF GROWTH FACTORS: ESSENTIAL ROLES AND FUNCTIONAL REDUNDANCY IN THE NERVE SYSTEM

Cory J. Xian 1 and Xin-Fu Zhou 2

1 Department of Orthopaedic Surgery, Women's and Children's Hospital, Adelaide, Australia, and 2 Department of Human Physiology, Flinders University, Adelaide, Australia

TABLE OF CONTENTS

1. Abstract
2. Introduction
3. Expression of EGF-R and ligands in the nervous system
4. Roles in the central nervous system
4.1. Proliferation of precursor cells or stem cells and glial reaction
4.2. Cellular migration during CNS development
4.3. Neuronal and glial differentiation
4.4. Neurotrophic functions
5. Roles in the peripheral nervous system
6. Essential roles of and possible functional redundancy within the EGF family in the nerve system
7. Conclusions and perspective
8. Acknowledgments
9. References

1. ABSTRACT

Evidence has suggested that the epidermal growth factor receptor (EGF-R) and its ligands are important regulators for development and maintenance of various tissues including the nerve system. Gene knockout, transgenic or other in vivo and in vitro studies have demonstrated that these molecules, produced by neurons and glial cells, play important roles in regulating neural/glial precursor cell or stem cell proliferation, migration, differentiation and survival, in maintaining tissue homeostasis, and in regulating CNS gliosis and peripheral nerve injury responses. These studies have revealed that, despite a possible functional redundancy among the individual EGF family ligands, collectively EGF-R ligands are required for development and maintenance of the nerve system.