Title | Mice lacking Homer 1 exhibit a skeletal myopathy characterized by abnormal transient receptor potential channel activity. |
Publication Type | Journal Article |
Year of Publication | 2008 |
Authors | JA Stiber, Z-S Zhang, J Burch, JP Eu, S Zhang, GA Truskey, M Seth, N Yamaguchi, G Meissner, R Shah, PF Worley, RS Williams, and PB Rosenberg |
Journal | Molecular and Cellular Biology |
Volume | 28 |
Issue | 8 |
Start Page | 2637 |
Pagination | 2637 - 2647 |
Date Published | 04/2008 |
Abstract | Transient receptor potential (TRP) channels are nonselective cation channels, several of which are expressed in striated muscle. Because the scaffolding protein Homer 1 has been implicated in TRP channel regulation, we hypothesized that Homer proteins play a significant role in skeletal muscle function. Mice lacking Homer 1 exhibited a myopathy characterized by decreased muscle fiber cross-sectional area and decreased skeletal muscle force generation. Homer 1 knockout myotubes displayed increased basal current density and spontaneous cation influx. This spontaneous cation influx in Homer 1 knockout myotubes was blocked by reexpression of Homer 1b, but not Homer 1a, and by gene silencing of TRPC1. Moreover, diminished Homer 1 expression in mouse models of Duchenne's muscular dystrophy suggests that loss of Homer 1 scaffolding of TRP channels may contribute to the increased stretch-activated channel activity observed in mdx myofibers. These findings provide direct evidence that Homer 1 functions as an important scaffold for TRP channels and regulates mechanotransduction in skeletal muscle. |
DOI | 10.1128/MCB.01601-07 |
Short Title | Molecular and Cellular Biology |