Autonomous expression of a noncatalytic domain of the focal adhesion-associated protein tyrosine kinase pp125FAK.
Integrins play a central role in cellular adhesion and anchorage of the cytoskeleton and participate in the generation of intracellular signals, including tyrosine phosphorylation. We have recently isolated a cDNA encoding a unique, focal adhesion-associated protein tyrosine kinase (FAK) that is a component of an integrin-mediated signal transduction pathway. Here we report the isolation of cDNAs encoding the C-terminal, noncatalytic domain of the FAK kinase, termed FRNK (FAK-related nonkinase). Both the FAK- and FRNK-encoded polypeptides, pp125FAK and p41/p43FRNK, are expressed in normal chicken embryo cells. pp125FAK and p41/p43FRNK were localized to focal adhesions, suggesting that pp125FAK is directed to the focal adhesions by sequences within its C-terminal domain. We also show that the fibronectin-dependent increase in tyrosine phosphorylation of pp125FAK is accompanied by a concomitant posttranslational modification of p41FRNK.
Schaller
M D
MD
Department of Microbiology and Cancer Center, University of Virginia Health Sciences Center, Charlottesville 22908.
Borgman
C A
CA
Parsons
J T
JT
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000235:genetics* / Q000378:metabolism; D002642:Chick Embryo; D004247:DNA; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D008969:Molecular Sequence Data; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D011505:Protein-Tyrosine Kinases / Q000235:genetics* / Q000378:metabolism
D015815:Cell Adhesion Molecules; D004247:DNA; D011505:Protein-Tyrosine Kinases; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases