Effects of mutant ILKs lacking kinase activity in mutant cells. (A) Immunoblotting showing protein expression of GFPILK-WT and kinase-dead ILK mutants (GFPILK-K220M and GFPILK-S343A). Whole-cell lysates were electrophoresed on SDS-PAGE and immunoblotted with rabbit anti-GFP polyclonal, rabbit anti-ILK polyclonal, or rabbit anti-GAPDH polyclonal Ab. (B) The activation indexes of transfectants. The activation index was determined by the formula shown in “Flow cytometry.” A value of 100% represents maximal PAC-1 binding in the cells treated with DTT. Data are mean plus or minus SD of 3 independent experiments.