| First Author | Booth RA | Year | 2002 |
| Journal | J Biol Chem | Volume | 277 |
| Issue | 8 | Pages | 6719-25 |
| PubMed ID | 11751850 | Mgi Jnum | J:74746 |
| Mgi Id | MGI:2159053 | Doi | 10.1074/jbc.M108033200 |
| Citation | Booth RA, et al. (2002) GIPC participates in G protein signaling downstream of insulin-like growth factor 1 receptor. J Biol Chem 277(8):6719-25 |
| abstractText | Several recent studies have demonstrated that insulin-like growth factor (IGF)-1-induced mitogen-activated protein kinase (MAP kinase) activation is abolished by pertussis toxin, suggesting that trimeric G proteins of the G(i) class are novel cellular targets of the IGF-1 signaling pathway. We report here that the intracellular domain of the Xenopus IGF-1 receptor is capable of binding to the Xenopus homolog of mammalian GIPC, a PDZ domain-containing protein previously identified as a binding partner of G(i)-specific GAP (RGS-GAIP). Binding of xGIPC to xIGF-1 receptor is independent of the kinase activity of the receptor and appears to require the PDZ domain of xGIPC. Injection of two C-terminal truncation mutants that retained the PDZ domain blocked IGF-1-induced Xenopus MAP kinase activation and oocyte maturation. While full-length xGIPC injection did not significantly alter insulin response, it greatly enhanced human RGS-GAIP in stimulating the insulin response in frog oocytes. This represents the first demonstration that GIPC x RGS-GAIP complex acts positively in IGF-1 receptor signal transduction. |
