Figure 3. In-gel kinase assays.

Triton-skinned rat caudal arterial smooth muscle (lanes 1 and 4; two muscle strips), tissue-purified ILK containing a small amount of ZIPK (lanes 2 and 5; 30 μl) and recombinant ZIPK (lanes 3 and 6; 0.125 μg) were subjected to SDS/PAGE in a gel containing purified LC₂₀ (lanes 1–3) or an identical gel without LC₂₀ (lanes 4–6). Following electrophoresis, proteins were renatured in the gels, which were then incubated in the presence of [γ-³²P]ATP and absence of Ca²⁺. Phosphorylated proteins were detected by autoradiography (n=3). Numbers at the right indicate the sizes of molecular-mass markers (in kDa).