title: Bombesin and platelet-derived growth factor induce association of endogenous focal adhesion kinase with Src in intact Swiss 3T3 cells.
abstract: Stimulation of quiescent Swiss 3T3 cells with bombesin induces a rapid increase in the formation of complexes between focal adhesion kinase (FAK) and Src family members, which can be extracted with a buffer containing Triton, deoxycholate, and SDS but not with a buffer containing Triton alone. An increase in complex formation between FAK and Src in response to bombesin could be detected within 1 min, reached a maximum after 10 min, and declined toward base-line levels after 60 min of bombesin treatment. Bradykinin, endothelin, and lysophosphatidic acid also stimulated FAK-Src complex formation. Bombesin stimulated FAK/Src association through a Ca(2+) and phosphatidylinositol 3'-kinase-independent pathway that requires the integrity of the actin filament network and is partly dependent on functional protein kinase C. Treatment with the selective Src kinase inhibitor PP-2 inhibited both FAK activation and phosphorylation of FAK at Tyr(577) induced by bombesin in intact cells. Platelet-derived growth factor at low concentrations (1-10 ng/ml) also induced FAK-Src complex formation via a pathway that depended on the integrity of the actin cytoskeleton and phosphatidylinositol 3'-kinase. Thus, G protein-coupled receptor agonists and platelet-derived growth factor promote complex formation between endogenous FAK and Src in attached cells through different signal transduction pathways.
authors.affiliation: Department of Medicine, School of Medicine, Molecular Biology Institute, UCLA, Los Angeles, California 90095, USA.
authors.forename: E P
authors.initials: EP
authors.lastname: Salazar
authors.forename: E
authors.initials: E
authors.lastname: Rozengurt
mesh_terms: D016475:3T3 Cells; D000199:Actins / Q000378:metabolism; D000818:Animals; D001839:Bombesin / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D003599:Cytoskeleton / Q000378:metabolism; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D051379:Mice; D015688:Oncogene Protein pp60(v-src) / Q000378:metabolism*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology*; D011485:Protein Binding; D011493:Protein Kinase C / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*
chemical_list: D000199:Actins; D015815:Cell Adhesion Molecules; D010982:Platelet-Derived Growth Factor; D019869:Phosphatidylinositol 3-Kinases; D011505:Protein-Tyrosine Kinases; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D015688:Oncogene Protein pp60(v-src); C496051:Ptk2 protein, mouse; D011493:Protein Kinase C; D001839:Bombesin; D002118:Calcium