Urea-SDS-glycerol/PAGE analysis of RLC phosphorylation. RLC, and P + RLC indicate unphosphorylated and phosphorylated RLC, respectively. All myosins were poorly phosphorylated before kinase treatment and, with the exception of MyΔC1528, were well phosphorylated after the treatment with kinase. C-A, chimera A; C-B, chimera B.