Helmholtz Gemeinschaft


Distinct interactions between actin and essential myosin light chain isoforms

Item Type:Article
Title:Distinct interactions between actin and essential myosin light chain isoforms
Creators Name:Petzhold, D. and Simsek, B. and Meißner, R. and Mahmoodzadeh, S. and Morano, I.
Abstract:Binding of the utmost N-terminus of essential myosin light chains (ELC) to actin slows down myosin motor function. In this study, we investigated the binding constants of two different human cardiac ELC isoforms with actin. We employed circular dichroism (CD) and surface plasmon resonance (SPR) spectroscopy to determine structural properties and protein-protein interaction of recombinant human atrial and ventricular ELC (hALC-1 and hVLC-1, respectively) with {alpha}-actin as well as {alpha}-actin with alanin-mutated ELC binding site ({alpha}-actin(ala3)) as control. CD spectroscopy showed similar secondary structure of both hALC-1 and hVLC-1 with high degree of {alpha}-helicity. SPR spectroscopy revealed that the affinity of hALC-1 to {alpha}-actin (KD = 575 nM) was significantly (p<0.01) lower compared with the affinity of hVLC-1 to {alpha}-actin (KD = 186 nM). The reduced affinity of hALC-1 to {alpha}-actin was mainly due to a significantly (p<0.01) lower association rate (kon: 1018 M(-1)s(-1)) compared with kon of the hVLC-1/{alpha}-actin complex interaction (2908 M(-1)s(-1)). Hence, differential expression of ELC isoforms could modulate muscle contractile activity via distinct {alpha}-actin interactions.
Keywords:Essential Myosin Light Chains, Actin Interaction, Surface Plasmon Resonance
Source:Biochemical and Biophysical Research Communications
Publisher:Elsevier / Academic Press
Page Range:284-288
Date:4 July 2014
Official Publication:https://doi.org/10.1016/j.bbrc.2014.05.040
PubMed:View item in PubMed

Repository Staff Only: item control page

Open Access
MDC Library