Epidermal growth factor receptor expression regulates proliferation in the postnatal rat retina
Article first published online: 18 MAY 2006
Copyright © 2006 Wiley-Liss, Inc.
Volume 54, Issue 2, pages 94–104, 1 August 2006
How to Cite
Close, J. L., Liu, J., Gumuscu, B. and Reh, T. A. (2006), Epidermal growth factor receptor expression regulates proliferation in the postnatal rat retina. Glia, 54: 94–104. doi: 10.1002/glia.20361
- Issue published online: 26 JUN 2006
- Article first published online: 18 MAY 2006
- Manuscript Accepted: 19 APR 2006
- Manuscript Received: 10 JAN 2006
- NIH. Grant Numbers: RO1 EY13475, RO1 NS28308
- NIH Institutional Neurobiology Training. Grant Number: T32 GM07108
Epidermal growth factor (EGF) is known to promote proliferation of both retinal progenitors and Muller glia in vitro, but several questions remain concerning an in vivo role for this factor. In this study, we investigated whether the EGF receptor (EGFR) is necessary for the maintenance of normal levels of progenitor and Muller glial proliferation in vivo. Here, we show that (1) mice with homozygous deletion of the Egfr gene have reduced proliferation in late stages of retinal histogenesis, (2) EGF is mitogenic for Müller glia in vivo during the first two postnatal weeks in the rodent retina, (3) the effectiveness of EGF as a Müller glial mitogen declines in parallel with the decline in EGFR expression as the retina matures, and (4) following damage to the retina from continuous light exposure, EGFR expression is up-regulated in Müller glia to levels close to those in the neonatal retina, resulting in a renewed mitotic response to EGF. Together with previous results from other studies, these data indicate that the downregulation of a growth factor receptor is one mechanism by which glial cells maintain mitotic quiescence in the mature nervous system. © 2006 Wiley-Liss, Inc.