JCB logo
Accuri Cytometers
  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents

Published 25 November 2002. doi:10.1083/jcb.200202117
This Article
Right arrow Full Text
Right arrow Full Text (PDF, 544K)
Right arrow PPT slides of all figures
Right arrow Alert me when this article is cited
Right arrow Citation Map
Services
Right arrow Email this article
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new content in the JCB
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Tsubouchi, A.
Right arrow Articles by Sabe, H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Tsubouchi, A.
Right arrow Articles by Sabe, H.
Social Bookmarking
 Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati  
What's this?
© The Rockefeller University Press, 0021-9525/2002/11/673 $5.00
The Journal of Cell Biology, Volume 159, Number 4, 673-683


Article

Localized suppression of RhoA activity by Tyr31/118-phosphorylated paxillin in cell adhesion and migration

Asako Tsubouchi1,2, Junko Sakakura1, Ryohei Yagi1, Yuichi Mazaki1, Erik Schaefer3, Hajime Yano1 and Hisataka Sabe1,2

1 Department of Molecular Biology, Osaka Bioscience Institute, Osaka 565-0874, Japan
2 Graduate School of Biostudies, Kyoto University, Sakyoku, Kyoto 606-8502, Japan
3 BioSource International, Hopkinton, MA 01748

Address correspondence to Hisataka Sabe, Dept. of Molecular Biology, Osaka Bioscience Institute, Osaka 565-0874, Japan. Tel.: 81-6-6872-4814. Fax: 81-6-6871-6686. E-mail: sabe{at}obi.or.jp

RhoA activity is transiently inhibited at the initial phase of integrin engagement, when Cdc42- and/or Rac1-mediated membrane spreading and ruffling predominantly occur. Paxillin, an integrin-assembly protein, has four major tyrosine phosphorylation sites, and the phosphorylation of Tyr31 and Tyr118 correlates with cell adhesion and migration. We found that mutation of Tyr31/118 caused enhanced activation of RhoA and premature formation of stress fibers with substantial loss of efficient membrane spreading and ruffling in adhesion and migration of NMuMG cells. These phenotypes were similar to those induced by RhoA(G14V) in parental cells, and could be abolished by expression of RhoA(T19N), Rac1(G12V), or p190RhoGAP in the mutant-expressing cells. Phosphorylated Tyr31/118 was found to bind to two src homology (SH)2 domains of p120RasGAP, with coprecipitation of endogenous paxillin with p120RasGAP. p190RhoGAP is known to be a major intracellular binding partner for the p120RasGAP SH2 domains. We found that Tyr31/118-phosphorylated paxillin competes with p190RhoGAP for binding to p120RasGAP, and provides evidence that p190RhoGAP freed from p120RasGAP efficiently suppresses RhoA activity during cell adhesion. We conclude that Tyr31/118-phosphorylated paxillin serves as a template for the localized suppression of RhoA activity and is necessary for efficient membrane spreading and ruffling in adhesion and migration of NMuMG cells.

Key Words: paxillin; p120RasGAP; RhoA; p190RhoGAP; tyrosine phosphorylation


Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati    What's this?


This article has been cited by other articles:



  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents