Format

Send to

Choose Destination
EMBO J. 1994 Oct 17;13(20):4745-56.

Association of the amino-terminal half of c-Src with focal adhesions alters their properties and is regulated by phosphorylation of tyrosine 527.

Author information

1
Department of Microbiology and Immunology, University of California, San Francisco 94143.

Abstract

We have characterized the mechanism by which the subcellular distribution of c-Src is controlled by the phosphorylation of tyrosine 527. Mutation of this tyrosine dramatically redistributes c-Src from endosomal membranes to focal adhesions. Redistribution to focal adhesions occurs independently of kinase activity and cellular transformation. In cells lacking the regulatory kinase (CSK) that phosphorylates tyrosine 527, c-Src is also found predominantly in focal adhesions, confirming that phosphorylation of tyrosine 527 affects the location of c-Src inside the cell. The first 251 amino acids of c-Src are sufficient to allow association with focal adhesions, indicating that at least one signal for positioning c-Src in focal adhesions resides in the amino-terminal half. Point mutations and deletions in the first 251 amino acids of c-Src reveal that association with focal adhesions requires the myristylation site needed for membrane attachment, as well as the SH3 domain. Expression of the amino-terminal region alters both the structural and biochemical properties of focal adhesions. Focal adhesions containing this non-catalytic portion of c-Src are larger and exhibit increased levels of phosphotyrosine staining. Our results suggest that c-Src may regulate focal adhesions and cellular adhesion by a kinase-independent mechanism.

PMID:
7525268
PMCID:
PMC395413
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Wiley Icon for PubMed Central
Loading ...
Support Center