Pyk2 facilitates FAK^−/− MEFs' proliferation and motility. (A) FAK^−/−, FAK^+/+, and FAK-reconstituted (DP3) MEF proliferation was evaluated over 5 d and shows that FAK^−/− MEFs do not exhibit growth defects. (B) FAK^−/− vector, FAK^−/− Scr shRNA, and FAK^−/− Pyk2 shRNA MEF proliferation was evaluated over 5 d and shows that Pyk2 shRNA expression is associated with reduced growth. (C) Transient Ad-FAK or Ad-Pyk2 expression enhances FAK^−/− Pyk2 shRNA MEF proliferation. Cells were infected for 24 h with the indicated control Ad-TA, Ad-FAK, or Ad-Pyk2 constructs before initiating growth analyses. Values in A–C are means ± SD of three experiments. (D) Lysates from FAK^−/− vector and Pyk2 shRNA MEFs infected with Ad-FAK or Ad-Pyk2 were resolved by SDS-PAGE and analyzed by HA-tag, Pyk2, and actin blotting. (E) FAK promotes FAK^−/− MEF motility better than Pyk2. The indicated MEFs were analyzed for 10-μg/ml-FN–stimulated Boyden chamber motility over 4 h and values are expressed as a percentage of FAK^−/− vector control (set to 100). As indicated, FAK^−/− vector shRNA or FAK^−/− Pyk2 shRNA MEFs were infected with Ad-FAK or Ad-Pyk2 for 48 h and analyzed for motility responses. Values ± SD are from three separate experiments.