Stabilization of the Central Part of Tropomyosin Molecule Alters the Ca2+-sensitivity of Actin-Myosin Interaction.
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ABSTRACT:
SUBMITTER: Shchepkin DV
PROVIDER: S-EPMC3848074 | biostudies-literature | 2013 Jul
REPOSITORIES: biostudies-literature
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Stabilization of the Central Part of Tropomyosin Molecule Alters the Ca2+-sensitivity of Actin-Myosin Interaction.
Shchepkin D V DV Matyushenko A M AM Kopylova G V GV Artemova N V NV Bershitsky S Y SY Tsaturyan A K AK Levitsky D I DI
Acta naturae 20130701 3
We show that the mutations D137L and G126R, which stabilize the central part of the tropomyosin (Tm) molecule, increase both the maximal sliding velocity of the regulated actin filaments in the in vitro motility assay at high Са(2+) concentrations and the Са(2+)-sensitivity of the actin-myosin interaction underlying this sliding. Based on an analysis of the recently published data on the structure of the actin-Tm-myosin complex, we suppose that the physiological effects of these mutations in Tm ...[more]
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