Mos positively regulates Xe-Wee1 to lengthen the first mitotic cell cycle of Xenopus
AUTOR(ES)
Murakami, Monica S.
FONTE
Cold Spring Harbor Laboratory Press
RESUMO
Several key developmental events occur in the first mitotic cell cycle of Xenopus; consequently this cycle has two gap phases and is ∼60–75 min in length. In contrast, embryonic cycles 2–12 consist only of S and M phases and are 30 min in length. Xe-Wee1 and Mos are translated and degraded in a developmentally regulated manner. Significantly, both proteins are present in the first cell cycle. We showed previously that the expression of nondegradable Mos, during early interphase, delays the onset of M phase in the early embryonic cell cycles. Here we report that Xe-Wee1 is required for the Mos-mediated M-phase delay. We find that Xe-Wee1 tyrosine autophosphorylation positively regulates Xe-Wee1 and is only detected in the first 30 min of the first cell cycle. The level and duration of Xe-Wee1 tyrosine phosphorylation is elevated significantly when the first cell cycle is elongated with nondegradable Mos. Importantly, we show that the tyrosine phosphorylation of Xe-Wee1 is required for the Mos-mediated M-phase delay. These findings indicate that Mos positively regulates Xe-Wee1 to generate the G2 phase in the first cell cycle and establish a direct link between the MAPK signal transduction pathway and Wee1 in vertebrates.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=316506Documentos Relacionados
- Cell cycle regulation of a Xenopus Wee1-like kinase.
- Absence of Wee1 ensures the meiotic cell cycle in Xenopus oocytes
- c-Mos forces the mitotic cell cycle to undergo meiosis II to produce haploid gametes
- The existence of two distinct Wee1 isoforms in Xenopus: implications for the developmental regulation of the cell cycle
- Cell cycle regulation of human WEE1.