Xp38γ/SAPK3 promotes meiotic G2/M transition in Xenopus oocytes and activates Cdc25C
Xp38γ/SAPK3 promotes meiotic G2/M transition in Xenopus oocytes and activates Cdc25C
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Xp38γ/SAPK3 促进非洲爪蟾卵母细胞减数分裂 G2/M 转变并激活 Cdc25C
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
A. Nebreda
中科院分区：
文献类型：
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作者：
Eusebio Perdiguero;M. Pillaire;J. Bodart;F. Hennersdorf;M. Frödin;N. Duesbery;G. Alonso;A. Nebreda
我们研究了p38丝裂原活化蛋白激酶（MAPK）在非洲爪蟾卵母细胞减数分裂成熟中的作用。p38激活剂MKK 6的组成型活性突变体的过表达加速孕酮诱导的成熟。免疫沉淀实验表明，卵母细胞中p38γ/SAPK 3是MKK 6激活的主要p38蛋白。我们克隆了非洲爪蟾p38γ（Xp 38 γ），并表明活性MKK 6与Xp 38 γ的共表达在不存在孕酮的情况下诱导卵母细胞成熟。Xp 38 γ诱导的成熟既不需要蛋白质合成，也不需要p42 MAPK-p90 Rsk通路的激活，但它被cAMP依赖性蛋白激酶阻断。内源性Xp 38 γ在孕酮诱导的成熟中的作用得到了MKK 6和Xp 38 γ激酶死亡突变体的抑制作用的支持。此外，MKK 6可以拯救炭疽致死因子（一种使MAPK激酶失活的蛋白酶）对卵母细胞成熟的抑制。我们还发现Xp 38 γ可以激活磷酸酶XCdc 25 C，并且我们确定XCdc 25 C的Ser 205是Xp 38 γ的主要磷酸化位点。我们的研究结果表明Xp 38 γ/SAPK 3对XCdc 25 C的磷酸化对非洲爪蟾卵母细胞减数分裂的G2/M进程是重要的。
We have studied the role of p38 mitogen‐activated protein kinases (MAPKs) in the meiotic maturation of Xenopus oocytes. Overexpression of a constitutively active mutant of the p38 activator MKK6 accelerates progesterone‐induced maturation. Immunoprecipit ation experiments indicate that p38γ/SAPK3 is the major p38 activated by MKK6 in the oocytes. We have cloned Xenopus p38γ (Xp38γ) and show that co‐expression of active MKK6 with Xp38γ induces oocyte maturation in the absence of progesterone. The maturation induced by Xp38γ requires neither protein synthesis nor activation of the p42 MAPK–p90Rsk pathway, but it is blocked by cAMP‐dependent protein kinase. A role for the endogenous Xp38γ in progesterone‐induced maturation is supported by the inhibitory effect of kinase‐dead mutants of MKK6 and Xp38γ. Furthermore, MKK6 can rescue the inhibition of oocyte maturation by anthrax lethal factor, a protease that inactivates MAPK kinases. We also show that Xp38γ can activate the phosphatase XCdc25C, and we identified Ser205 of XCdc25C as a major phosphorylation site for Xp38γ. Our results indicate that phosphorylation of XCdc25C by Xp38γ/SAPK3 is important for the meiotic G2/M progression of Xenopus oocytes.
影响因子：
16
作者：
Chang, CI;Xu, BE;Goldsmith, EJ
通讯作者：
Goldsmith, EJ
影响因子：
3.3
作者：
IZUMI, T;MALLER, JL
通讯作者：
MALLER, JL