RhoA-dependent ROCKII activation is sensitive to Y722 dephosphorylation. (A) In vitro kinase assay in the absence or presence of 0.1 or 1 μM GTPγS-GST-RhoA protein with wild-type or Y722F myc-ROCKII immunoprecipitates from transfected cells treated with or without pervanadate. Inset indicates the phosphorylation status of ROCKII by Western blotting with anti-pY (4G10) antibody. (B) Comparison of RhoA-dependent kinase activation of Y722F and Y722D myc-ROCKII. Data are expressed as fold increase relative to wild-type myc-ROCKII without GTP-RhoA stimulation (mean ± SD; **, P < 0.05).