Purchase this article with an account.
D. Hamassaki–Britto, M.A. Belmonte, L.M. Castro, M.F. Santos; PHOTORECEPTOR DEGENERATION INDUCES AN INCREASE IN Rac1 EXPRESSION . Invest. Ophthalmol. Vis. Sci. 2004;45(13):3613.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose:To investigate the expression of the Rho GTPases Rac1 and Cdc42 and their effectors p21–activated kinases 1–4 (PAKs) in two models of retinal degeneration: light–induced and rd mice. Methods:Adult Balb/c mice dark–adapted for 18h were light–stimulated (5000 lux) for 2h, and immediately sacrificed or kept in the dark for additional 6, 14 or 24 h. Rd mice (C3H/HeJ) were sacrificed at postnatal days 9, 11 or 15 days. The eyes were enucleated and processed for immunofluorescence. Apoptosis was evaluated using TUNEL. Results:Although not visible in the control, Rac1 expression in the outer nuclear layer (ONL) became progressively evident after light stimulation, reaching its maximum after 24 h. Similar observation was made in rd mice: the number of Rac1–positive cells in the ONL was higher in 11 days–old, when compared to 9 days–old animals. From 15 days–old on, Rac1 labeling became reduced. Cdc42 was not expressed in Balb/c and rd photoreceptors. In Balb/c mice, only PAKs 3 and 4 were expressed in photoreceptors. PAK 3 was present in the outer segments, whereas PAK4 was uniformly distributed throughout the ONL. Photoreceptor degeneration apparently did not alter the distribution of these proteins. Conclusions:The results suggest a role for Rac1 during photoreceptor degeneration in mice, in a pathway that might involve PAKs 3 and 4.
This PDF is available to Subscribers Only