Abstract 359: Tripartite Motif Protein 58 (trim58) is a Novel Regulator of Membrane Repair With Increased Expression in Failing Cardiac Muscle

Abstract

In recent years, members of the tripartite motif-containing (TRIM) family of E3 ubiquitin ligases have been shown to be both positively and negatively regulated in various disease pathologies. TRIM72 (MG53) has been directly linked with regulation of sarcolemmal membrane repair in striated muscle cells, including cardiomyocytes. Recently, we were first to identify that a novel tripartite motif family member, TRIM58, is a negative regulator of the cell membrane repair process in striated muscle cells. Overexpression of TRIM58 decreases the membrane repair capacity of cultured myoblasts as measured by dye occlusion following laser-mediated disruption of the sarcolemmal membrane. We also find that TRIM58 can directly interact with TRIM72/MG53 and alter signaling through phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K). Protein profiling experiments show that TRIM58 expression increases during the development of heart failure suggesting that TRIM58 may be relevant in the development of cardiac failure. Western blot and histological examination in both human (Fig.1) and mouse transverse aortic constriction (TAC) heart failure samples clearly show an increased expression of TRIM58 in cardiac tissue. Our results suggest that TRIM58 levels might serve as a potential prognostic marker and that TRIM58 may be a therapeutic target for the management of cardiovascular disease.