FIG. 3.
Relative tyrosine phosphorylation of WT-, F397-, and F576/F577-FAK in Tet-FAK cells growing under normal culture conditions. Tet-FAK cells were induced for either 2 days [Tet-FAK(WT)-46 and Tet-FAK(F576/F577)-16] or 12 h [Tet-FAK(F397)-21] to obtain near-equal levels of expression of the FAK variants, and then FAK was immunoprecipitated (IP) from RIPA buffer lysates containing 650 μg of total protein. The immunoprecipitates were then divided equally for immunoblot (IB) analysis by using either antiphosphotyrosine antibody 4G10 (top panel) or anti-FAK antibody C-20 (bottom panel). Immunoblots were developed by enhanced chemiluminescence, and signals were quantitated from digitized images.