Myosin 19 is an Outer Mitochondrial Membrane Motor and Effector of Starvation Induced Filopodia with Unique Kinetic Features

Abstract

suggesting that the presence of the COL5A2 mutation in P2 has not altered the clinical phenotype. The potential contribution of these mutations to phenotype using molecular modelling will be presented. This is the first instance where double-hit muta-tions have been described in familial TAA but the effect of multiple mutations on phenotype appears to be variable. Mutation analysis for individuals with fa-milial TAA should look beyond the identification of a single gene culprit. The rate of actin and myosin rigor binding depends on the ionic strength of the solution, confirming that actomyosin interaction is electrostatically driven. The dependence of the rate of actin and myosin interaction on the ionic strength of the solution reflects the charge of the interface of the interacting molecules. We used fluorescence of pyrene labeled actin to measure transient kinetics of acto-myosin rigor binding in buffered solutions of different ionic strength and con-stant pH. We used recent data on the structure of actomyosin complex [1] to determine the charge and charge distribution of the actin binding interface of myosin head. The experimental transient kinetics data and the computational analysis were used to compare cellular and muscle myosin in terms of similar-ities and differences of their actin binding interface. 1. Behrmann, E., et al., Structure of the rigor actin-tropomyosin-myosin com-plex. Cell, 2012. 150(2): p. 327-38.