| First Author | Sette C | Year | 2002 |
| Journal | EMBO J | Volume | 21 |
| Issue | 20 | Pages | 5386-95 |
| PubMed ID | 12374739 | Mgi Jnum | J:79575 |
| Mgi Id | MGI:2388511 | Doi | 10.1093/emboj/cdf553 |
| Citation | Sette C, et al. (2002) Tr-kit-induced resumption of the cell cycle in mouse eggs requires activation of a Src-like kinase. EMBO J 21(20):5386-95 |
| abstractText | Microinjection in mouse eggs of tr-kit, a truncated form of the c-kit tyrosine kinase present in mouse spermatozoa, causes resumption of meiosis through activation of phospholipase Cgamma1 (PLCgamma1) and Ca(2+) mobilization from intracellular stores. We show that the Src-like kinase Fyn phosphorylates Tyr161 in tr-kit and that this residue is essential for tr-kit function. Fyn is localized in the cortex region underneath the plasma membrane in mouse oocytes. Using several approaches, we demonstrate that Fyn associates with tr-kit and that the interaction requires Tyr161. The interaction between tr-kit and Fyn triggers activation of the kinase as monitored by both autophosphorylation and phosphorylation of PLCgamma1. Co-injection of tr-kit with the SH2 domain of Fyn, or pre-treatment with a Fyn inhibitor, impairs oocyte activation, suggesting that activation of Fyn by tr-kit also occurs in vivo. Finally, microinjection of constitutively active Fyn triggers oocyte activation downstream of tr-kit but still requires PLC activity. We suggest that the mechanism by which tr-kit triggers resumption of meiosis of mouse eggs requires a functional interaction with Fyn and phosphorylation of PLCgamma1. |
