FIGURE 3.

Effect of ZIPK knockdown on cardiac RLC phosphorylation in intact myocytes. A, NRCM were transfected with 10 nm of negative control or ZIPK-targeted siRNA (siZIPK, ABI siRNA sequence number s64814) and harvested 72 h after transfection for Western blot analysis with antibodies against ZIPK, GAPDH (load control), phospho-cardiac RLC (RLC-P), smooth muscle myosin light chain kinase (smMLCK), and cardiac myosin light chain kinase (cMLCK). B, densitometric quantitation of samples treated with siRNA for amounts of ZIPK (open) and RLC-P (hatched) normalized to negative control-siRNA transfected sample median values (filled). **, p < 0.001, n = 3.