Fig. 7. Cdk5 phosphorylates paxillin at Ser244 in vitro. (A) Immobilized paxillin constructs were incubated with recombinant Cdk5 and p25, and immunoblotted with antibody recognizing phosphorylated Cdk substrate. Total levels of GFP-paxillin are also shown. (B) Quantification of the intensity of the bands shown in the immunoblots.