Implication of the small GTPase Rac1 in the apoptosis induced by UV in rat-2 fibroblasts

Citation
Yw. Eom et al., Implication of the small GTPase Rac1 in the apoptosis induced by UV in rat-2 fibroblasts, BIOC BIOP R, 285(3), 2001, pp. 825-829
Citations number
27
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biochemistry & Biophysics
Journal title
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
ISSN journal
0006-291X → ACNP
Volume
285
Issue
3
Year of publication
2001
Pages
825 - 829
Database
ISI
SICI code
0006-291X(20010720)285:3<825:IOTSGR>2.0.ZU;2-3
Abstract
Exposure of mammalian cells to ultraviolet (UV) light elicits a cellular re sponse and also lead to apoptotic cell death. However, the role of Rac, a m ember of Rho family GTPases, in the UV-induced apoptosis has never been exa mined. In UV-irradiated Rat-2 fibroblasts, nuclear fragmentation began to b e observed within 2 h and the total viability of Rat-2 cells were only abou t 15% at 6 h following by UV irradiation, whereas the total viability in Ra t2-Rac(N17) cells stably expressing RacN17, a dominant negative Rac1 mutant , was almost close to 67%. Pretreatment with SB203580, a specific inhibitor of p38 kinase, likewise attenuated UV-induced cell death, but PD98059, a M EK inhibitor, did not. Thus, Rac1 and p38 kinase appear to be components in the apoptotic signaling pathway induced by UV irradiation in Rat-2 fibrobl asts. In addition, our results show that p38 kinase stimulation by UV is dr amatically inhibited by RacN17, suggesting that p38 kinase is situated down stream of Rac1 in the UV signaling to apoptosis. (C) 2001 Academic Press.