| First Author | Klein U | Year | 1997 |
| Journal | J Biol Chem | Volume | 272 |
| Issue | 31 | Pages | 19099-102 |
| PubMed ID | 9235896 | Mgi Jnum | J:41995 |
| Mgi Id | MGI:894915 | Doi | 10.1074/jbc.272.31.19099 |
| Citation | Klein U, et al. (1997) A novel interaction between adrenergic receptors and the alpha-subunit of eukaryotic initiation factor 2B. J Biol Chem 272(31):19099-102 |
| abstractText | The alpha-subunit of eukaryotic initiation factor 2B (eIF-2B), a guanine nucleotide exchange protein that functions in regulation of translation, was observed to associate with the carboxyl-terminal cytoplasmic domains of the alpha2A- and alpha2B-adrenergic receptors in a yeast two-hybrid screen of a cDNA library prepared from 293 cells. This protein association was confirmed in vitro by affinity chromatography and was shown to be specific for a subset of G protein-coupled receptors, including the alpha2A-, alpha2B-, alpha2C-, and beta2-adrenergic receptors, but not the vasopressin (V2) receptor. Association of these proteins in vivo was confirmed by specific co-immunoprecipitation of eIF-2Balpha with full-length beta2-adrenergic receptors expressed in transfected 293 cells and by fluorescence microscopy showing co-localization of these proteins in intact cells. Remarkably, eIF-2Balpha co-localized with receptors exclusively in regions of the plasma membrane that are in contact with the extracellular medium, but failed to associate with membranes making cell-cell contacts. Overexpression of eIF-2Balpha in 293 cells caused a small (approximately 15%) but significant enhancement of beta2-adrenergic receptor-mediated activation of adenylyl cyclase, without affecting forskolin or V2 receptor-mediated activation. These observations suggest a new role for a previously identified guanine nucleotide exchange protein in membrane biology and cell signaling. |
