Click here to close Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly. We suggest using a current version of Chrome, FireFox, or Safari.
XB-ART-14420
Mol Cell Biol 1998 Sep 01;189:5567-78. doi: 10.1128/MCB.18.9.5567.
Show Gene links Show Anatomy links

Ras-GAP controls Rho-mediated cytoskeletal reorganization through its SH3 domain.

Leblanc V , Tocque B , Delumeau I .


???displayArticle.abstract???
Proteins of the Ras superfamily, Ras, Rac, Rho, and Cdc42, control the remodelling of the cortical actin cytoskeleton following growth factor stimulation. A major regulator of Ras, Ras-GAP, contains several structural motifs, including an SH3 domain and two SH2 domains, and there is evidence that they harbor a signalling function. We have previously described a monoclonal antibody to the SH3 domain of Ras-GAP which blocks Ras signalling in Xenopus oocytes. We now show that microinjection of this antibody into Swiss 3T3 cells prevents the formation of actin stress fibers stimulated by growth factors or activated Ras, but not membrane ruffling. This inhibition is bypassed by coinjection of activated Rho, suggesting that the Ras-GAP SH3 domain is necessary for endogenous Rho activation. In agreement, the antibody blocks lysophosphatidic acid-induced neurite retraction in differentiated PC12 cells. Furthermore, we demonstrate that microinjection of full-length Ras-GAP triggers stress fiber polymerization in fibroblasts in an SH3-dependent manner, strongly suggesting an effector function besides its role as a Ras downregulator. These results support the idea that Ras-GAP connects the Ras and Rho pathways and, therefore, regulates the actin cytoskeleton through a mechanism which probably does not involve p190 Rho-GAP.

???displayArticle.pubmedLink??? 9710640
???displayArticle.pmcLink??? PMC109141
???displayArticle.link??? Mol Cell Biol


Species referenced: Xenopus
Genes referenced: actl6a cdc42 rac1 rho rho.2

References [+] :
Abdellatif, An effector-like function of Ras GTPase-activating protein predominates in cardiac muscle cells. 1997, Pubmed