Table of Contents
Journal of Signal Transduction
Volume 2012 (2012), Article ID 754964, 9 pages
http://dx.doi.org/10.1155/2012/754964
Research Article

Redox Regulation of Nonmuscle Myosin Heavy Chain during Integrin Engagement

Department of Biochemical Sciences, University of Florence, Viale Morgagni 50, 50134 Florence, Italy

Received 21 July 2011; Accepted 20 September 2011

Academic Editor: Lorenza Trabalzini

Copyright © 2012 Tania Fiaschi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

On the basis of our findings reporting that cell adhesion induces the generation of reactive oxygen species (ROS) after integrin engagement, we were interested in identifying redox-regulated proteins during this process. Mass spectrometry analysis led us to identify nonmuscle myosin heavy chain (nmMHC) as a target of ROS. Our results show that, while nmMHC is reduced in detached/rounded cells, it turns towards an oxidized state in adherent/spread cells due to the integrin-engaged ROS machinery. The functional role of nmMHC redox regulation is suggested by the redox sensitivity of its association with actin, suggesting a role of nmMHC oxidation in cytoskeleton movement. Analysis of muscle MHC (mMHC) redox state during muscle differentiation, a process linked to a great and stable decrease of ROS content, shows that the protein does not undergo a redox control. Hence, we propose that the redox regulation of MHC in nonprofessional muscle cells is mandatory for actin binding during dynamic cytoskeleton rearrangement, but it is dispensable for static and highly organized cytoskeletal contractile architecture in differentiating myotubes.