JCB logo
  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents
This Article
Right arrow Full Text
Right arrow Full Text (PDF, 1987K)
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 CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Kiosses, W. B.
Right arrow Articles by Schwartz, M. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Kiosses, W. B.
Right arrow Articles by Schwartz, M. A.
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Facebook   Add to Reddit   Add to Technorati   Add to Twitter  
What's this?

© The Rockefeller University Press, 0021-9525/1999//831 $5.00
The Journal of Cell Biology, Volume 147, Number 4, , 1999 831-844

Original Article

A Role for P21-Activated Kinase in Endothelial Cell Migration



William B. Kiossesa, R. Hugh Danielsb, Carol Oteyc, Gary M. Bokochb, and Martin Alexander Schwartza

a Department of Vascular Biology, The Scripps Research Institute, La Jolla, California 92037
b Departments of Immunology and Cell Biology, The Scripps Research Institute, La Jolla, California 92037
c Department of Physiology, University of North Carolina, Chapel Hill, North Carolina 27599
Department of Vascular Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037.(619) 784-7360(619) 784-7140

schwartz{at}scripps.edu

The serine/threonine p21-activated kinase (PAK) is an effector for Rac and Cdc42, but its role in regulating cytoskeletal organization has been controversial. To address this issue, we investigated the role of PAK in migration of microvascular endothelial cells. We found that a dominant negative (DN) mutant of PAK significantly inhibited cell migration and in-creased stress fibers and focal adhesions. The DN effect mapped to the most NH2-terminal proline-rich SH3-binding sequence. Observation of a green fluorescent protein-tagged {alpha}-actinin construct in living cells revealed that the DN construct had no effect on membrane ruffling, but dramatically inhibited stress fiber and focal contact motility and turnover. Constitutively active PAK inhibited migration equally well and also increased stress fibers and focal adhesions, but had a somewhat weaker effect on their dynamics. In contrast to their similar effects on motility, DN PAK decreased cell contractility, whereas active PAK increased contractility. Active PAK also increased myosin light chain (MLC) phosphorylation, as indicated by staining with an antibody to phosphorylated MLC, whereas DN PAK had little effect, despite the increase in actin stress fibers. These results demonstrate that although PAK is not required for extension of lamellipodia, it has substantial effects on cell adhesion and contraction. These data suggest a model in which PAK plays a role coordinating the formation of new adhesions at the leading edge with contraction and detachment at the trailing edge.

Key Words: Rac • Cdc42 • cell motility • cytoskeleton • contractility

© 1999 The Rockefeller University Press

Abbreviations used in this paper: AC, active CAAX tagged; EC, endothelial cell; DN, dominant negative; FN, fibronectin; GFP, green fluorescent protein; HMEC, human microvascular endothelial cells; JNK, Jun kinase; MLC, myosin light chain; PAK, p21-activated kinase; P-MLC, phosphorylated myosin light chain; WT, wild-type.


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 Facebook Facebook   Add to Reddit Reddit   Add to Technorati Technorati   Add to Twitter Twitter    What's this?




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