Work Phone Number:
Los Angeles, CA 90095 CHS
Los Angeles, CA 90095
|Professor Emeritus, Physiology|
Research Interest: Regulation of crossbridge mechanisms We study the mechanism by which muscle or other molecular motors convert chemical energy (ATP) into mechanical work force, and shortening (chemomechanical transduction) and the calcium regulation of these processes. For this we use a variety of biochemical and biophysical techniques including: measurement of force, displacement, and stiffness in single muscle cells contracting under controlled conditions; measurement of the force exerted on single reconstituted fluorescently labled thin filaments (using microneedles) and their unloaded sliding speed in in vitro motility assays; measurement of force transients using single isolated myofibrils; and meaurements of force and displacement produced by single myosin molecules using optical trapping techniques. Reconstituted thin filaments are constructed from native and/or molecularly engineered actin, tropomyosin and/or troponin. We hope to learn the size of the crossbridge power stroke, the rates of specific crossbridge reaction steps, the identity of those steps affected by force exerted, displacement, [Ca+2], and the mechanisms of effects of regulatory protein mutations associated with Familial Hypertrophic Cardiomyopathy.