Regulatory Light Chain (RLC)
Regulatory light chain (RLC) of vertebrate smooth and cardiac
myosins do not bind calcium but are an alternate source of calcium
regulation via a CAM activated kinase. Comparison of the crystal
structure of molluscan RLC with a Ca2+ ion bound in EF-hand 1 with both
chicken ELC and RLC complexed with the S1 fragment of myosin has
permitted Houdusse et al. to present a model of ELC and RLC
complexed with myosin in the active and inactive states.