Galpha11 induces caspase-mediated proteolytic activation of Rho-associated kinase, ROCK-I, in HeLa cells - PubMed (original) (raw)

. 2001 Nov 9;276(45):42527-33.

doi: 10.1074/jbc.M102529200. Epub 2001 Sep 6.

Affiliations

Free article

Galpha11 induces caspase-mediated proteolytic activation of Rho-associated kinase, ROCK-I, in HeLa cells

H Ueda et al. J Biol Chem. 2001.

Free article

Erratum in

Abstract

Expression of the constitutively active mutant of Galpha(11) (Galpha(11)QL) induces the formation of vinculin-containing focal adhesion-like structures in HeLa cells. This was found to be inhibited by Y-27632, a specific inhibitor of Rho-associated kinases (ROCK), but not by co-expression with a dominant negative mutant of RhoA, suggesting Rho-independent activation of ROCK by Galpha(11)QL. Investigation of trypan blue exclusion and immunocytochemistry with an antibody against cleaved caspase revealed the cellular phenotype of Galpha(11)QL-expressing cells to be identical to that displayed by cells undergoing apoptosis, and the caspase inhibitor zVAD-fmk blocked all morphological changes induced by Galpha(11)QL. Transfection of Galpha(11)QL induced cleavage of ROCK-I, and this proteolysis was also prevented by zVAD-fmk. ROCK-I C-terminally truncated at its authentic caspase sites also induced the formation of vinculin-containing focal adhesion-like structures. In addition, cleavage of ROCK-I was observed when cells overexpressing m1 muscarinic acetylcholine receptors were stimulated with carbachol. These results suggest that Galpha(11) induces proteolytic activation of ROCK-I by caspase and thereby regulates the actin cytoskeleton during apoptosis.

PubMed Disclaimer

Similar articles

Cited by

Publication types

MeSH terms

Substances

LinkOut - more resources