Regulation of motor force in skeletal muscle contraction
Bin Chen (Zhejiang univ.), Huajian Gao (Brown University)
Mechanics and Physics of Biological Cells
Wed 9:00 - 10:30
Barus-Holley 141
Coordinated and synchronous actions of multiple motors take place in various biological processes, including skeletal muscle contraction, cellular mitosis, and neuronal growth, etc. though the behavior of a single motor is essentially random. Here, we investigate the chemomechanical coupling within an actin-myosin-ATP cycle and show that a �working�Myosin II possesses a unique force-stretch curve. Further study demonstrates that this unique force-stretch relation together with the stochastic behavior of actin-myosin binding causes the average number of �working� Myosin IIs to increase in linear proportion to the filament load during skeletal muscle contraction at steady state, in excellent agreement with experiment.