Characterization of Cardiac Adiponectin Post-Translational Processing and Secretion

Abstract

Harris, Biophys. Soc. abstracts, 2012). To determine directly whether cMyBP-C binding affects tropomyosin position, we carried out 3D reconstruction of negatively stained thin filaments (containing F-actin, tropomyosin and troponin) decorated with the N-terminal fragment containing domains C0 to C2. Clear decoration was obtained under a variety of salt conditions. 3D reconstructions suggest that under most conditions cMyBP-C does not displace tropomyosin from its low Ca 2þ position, although under certain conditions some shift of tropomyosin did appear to occur. At high Ca 2þ , there was little effect on tropomyosin position. The results suggest that cMyBP-C may modulate thin filament function by physically competing with tropomyosin for its low Ca 2þ site on Factin.