Regulates myosin phosphatase activity. Augments Ca(2+) sensitivity of the contractile apparatus.
Cytoplasm, cytoskeleton . Cytoplasm, cytoskeleton, stress fiber . Along actomyosin filaments. .
Detected in skeletal muscle, fetal and adult heart, brain, placenta, kidney, spleen, thymus, pancreas and lung. Isoform 3 and isoform 4 are heart specific.