Phosphorylation of Ser283 enhances the stiffness of the tropomyosin head-to-tail overlap domain.

ABSTRACT: The ends of coiled-coil tropomyosin molecules are joined together by nine to ten residue-long head-to-tail "overlapping domains". These short four-chained interconnections ensure formation of continuous tropomyosin cables that wrap around actin filaments. Molecular Dynamics simulations indicate that the curvature and bending flexibility at the overlap is 10-20% greater than over the rest of the molecule, which might affect head-to-tail filament assembly on F-actin. Since the penultimate residue of striated muscle tropomyosin, Ser283, is a natural target of phosphorylating enzymes, we have assessed here if phosphorylation adjusts the mechanical properties of the tropomyosin overlap domain. MD simulations show that phosphorylation straightens the overlap to match the curvature of the remaind

SUBMITTER: Lehman W 

PROVIDER: S-EPMC4385494 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature