Tyrosine phosphorylation of pp125fak and paxillin in aortic
endothelial cells induced by mechanical strain.
Yano, Yoshiko, John Geibel, and Bauer E. Sumpio.
Department of Surgery, Yale University School of Medicine, New
Haven, CT, 06510
APStracts 3:0072C, 1996.
The objective of this study was to determine whether focal adhesion
proteins pp125FAK (focal adhesion kinase) and paxillin are
phosphorylated on tyrosine and might play a role in the morphological
change and cell migration induced by strain. Bovine aortic
endothelial cells (EC) were subjected to 10% average strain at 60
cycles/min. Cyclic strain increased tyrosine phosphorylation of
pp125FAK at 30 min (3.4-fold) and 4h (5.9-fold), and the tyrosine
phosphorylation of paxillin at 4h (2.0-fold). Confocal microscopy
showed that after 4h exposure of strain, EC began to elongate and F
-actin, pp125FAK and paxillin aligned, although they randomly
distribute in static condition. Tyrosine kinase inhibitor tyrphostin
A25 (100 [mu]M) inhibited not only tyrosine phosphorylation of
pp125FAK and paxillin but also the redistribution of pp125FAK and
paxillin, morphological change and migration of EC induced by strain.
These data demonstrate that cyclic strain induced tyrosine
phosphorylation and reorganization of pp125FAK and paxillin, and
suggest that these focal adhesion proteins play specific role in
cyclic strain induced morphological change and migration.
Received 5 January 1996; accepted in final form 23 February 1996.
APS Manuscript Number C7-6.
Article publication pending Am. J. Physiol. (Cell Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 20 March 96