| First Author | Béguin P | Year | 2005 |
| Journal | J Cell Sci | Volume | 118 |
| Issue | Pt 9 | Pages | 1923-34 |
| PubMed ID | 15860732 | Mgi Jnum | J:200310 |
| Mgi Id | MGI:5508269 | Doi | 10.1242/jcs.02321 |
| Citation | Beguin P, et al. (2005) 14-3-3 and calmodulin control subcellular distribution of Kir/Gem and its regulation of cell shape and calcium channel activity. J Cell Sci 118(Pt 9):1923-34 |
| abstractText | Individual members of the RGK family of Ras-related GTPases, which comprise Rad, Gem/Kir, Rem and Rem2, have been implicated in important functions such as the regulation of voltage-gated calcium channel activity and remodeling of cell shape. The GTPase Kir/Gem inhibits the activity of calcium channels by interacting with the beta-subunit and also regulates cytoskeleton dynamics by inhibiting the Rho-Rho kinase pathway. In addition, Kir/Gem interacts with 14-3-3 and calmodulin, but the significance of this interaction on Kir/Gem function is poorly understood. Here, we present a comprehensive analysis of the binding of 14-3-3 and calmodulin to Kir/Gem. We show that 14-3-3, in conjunction with calmodulin, regulates the subcellular distribution of Kir/Gem between the cytoplasm and the nucleus. In addition, 14-3-3 and calmodulin binding modulate Kir/Gem-mediated cell shape remodeling and downregulation of calcium channel activity. Competition experiments show that binding of 14-3-3, calmodulin and calcium channel beta-subunits to Kir/Gem is mutually exclusive, providing a rationale for the observed regulatory effects of 14-3-3 and calmodulin on Kir/Gem localization and function. |
