Fig. 5. PKC and Src family tyrosine kinases are required for the p130Cas/CrkII complex formation induced by gastrin. A and B, CHO cells expressing the human CCKBR were stimulated for the times indicated with 10 nM gastrin. C-F, after a 30-min preincubation with (+) or without (-) 5 µM GF109203X (GF) or 10 µM PP2, CHO cells expressing the human CCKBR were stimulated for 1 min with 10 nM gastrin or for 20 min with 100 nM PMA. Proteins from cell lysates were prepared and immunoprecipitated (IP) with anti-phosphotyrosine (P-Tyr; A, C, and E) or anti-CrkII (B, D, and F) antibodies and then subjected to p130Cas immunoblotting. Comparable amounts of proteins were detected in immunoprecipitates or whole cell lysates of all of the above-mentioned experiments (B, D, and F and data not shown). The autoradiograms were densitometrically analyzed, and the data from at least three separate autoradiograms were plotted as fold stimulation and presented as means ± SE.