Cardiac and skeletal actin substrates uniquely tune cardiac myosin strain-dependent mechanics.

ABSTRACT: Cardiac ventricular myosin (βmys) translates actin by transducing ATP free energy into mechanical work during muscle contraction. Unitary βmys translation of actin is the step-size. In vitro and in vivo βmys regulates contractile force and velocity autonomously by remixing three different step-sizes with adaptive stepping frequencies. Cardiac and skeletal actin isoforms have a specific 1 : 4 stoichiometry in normal adult human ventriculum. Human adults with inheritable hypertrophic cardiomyopathy (HCM) upregulate skeletal actin in ventriculum probably compensating the diseased muscle's inability to meet demand by adjusting βmys force-velocity characteristics. βmys force-velocity characteristics were compared for skeletal versus cardiac actin substrates using ensemble in vi

SUBMITTER: Wang Y 

PROVIDER: S-EPMC6282072 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature