Analytical comparison of natural and pharmaceutical ventricular myosin activators.

ABSTRACT: Ventricular myosin (βMys) is the motor protein in cardiac muscle generating force using ATP hydrolysis free energy to translate actin. In the cardiac muscle sarcomere, myosin and actin filaments interact cyclically and undergo rapid relative translation facilitated by the low duty cycle motor. It contrasts with high duty cycle processive myosins for which persistent actin association is the priority. The only pharmaceutical βMys activator, omecamtive mecarbil (OM), upregulates cardiac contractility in vivo and is undergoing testing for heart failure therapy. In vitro βMys step-size, motility velocity, and actin-activated myosin ATPase were measured to determine duty cycle in the absence and presence of OM. A new parameter, the relative step-frequency, was introduced and measured to charact

SUBMITTER: Wang Y 

PROVIDER: S-EPMC4139156 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature