Role of the essential light chain in the activation of smooth muscle myosin by regulatory light chain phosphorylation.

ABSTRACT: The activity of smooth and non-muscle myosin II is regulated by phosphorylation of the regulatory light chain (RLC) at serine 19. The dephosphorylated state of full-length monomeric myosin is characterized by an asymmetric intramolecular head-head interaction that completely inhibits the ATPase activity, accompanied by a hairpin fold of the tail, which prevents filament assembly. Phosphorylation of serine 19 disrupts these head-head interactions by an unknown mechanism. Computational modeling (Tama et al., 2005. J. Mol. Biol. 345, 837-854) suggested that formation of the inhibited state is characterized by both torsional and bending motions about the myosin heavy chain (HC) at a location between the RLC and the essential light chain (ELC). Therefore, altering relative motions between the E

SUBMITTER: Taylor KA 

PROVIDER: S-EPMC4065857 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature