Post-transcriptional regulation by insulin of Xenopus ribosomal protein S6 kinase.
Post-transcriptional regulation by insulin of Xenopus ribosomal protein S6 kinase.
复制标题
非洲爪蟾核糖体蛋白 S6 激酶胰岛素的转录后调节。
DOI：
10.1016/0014-4827(88)90352-7
复制
发表时间：
1988
影响因子：
3.7
通讯作者：
Maller,JL
中科院分区：
文献类型：
--
作者：
Stefanovic,D;Maller,JL
研究了卵母细胞成熟过程中卵母细胞核糖体蛋白S6激酶的激活。胰岛素治疗引起S6激酶的快速三倍激活，在胰岛素后2小时恢复到接近基础水平。其次是后来的5倍增加，从2至5小时与胰岛素，最终与萌发囊泡破裂。用多种蛋白质合成抑制剂预处理卵母细胞可增加基础活性水平，但胰岛素对S6激酶早期激活的时间过程没有明显改变。与此相反，在S6激酶活性的后期增加完全抑制预处理放线菌酮。然而，S6激酶活性的最大增加发生在注射促成熟因子后，即使在存在多种蛋白质合成抑制剂的情况下。短暂暴露于放线菌酮30分钟或更长时间的胰岛素刺激后，增加了胰岛素刺激的活动的幅度，而不改变活动增加的整体模式。这些结果表明，存在一种快速翻转的S6激酶抑制剂，胰岛素通过蛋白质合成依赖性和非依赖性机制激活S6激酶。
The activation ofXenopusoocyte ribosomal protein S6 kinase during oocyte maturation was investigated. Insulin treatment caused a rapid three-fold activation of S6 kinase that returned to near basal levels by 2 h postinsulin. This was followed by a later fivefold increase from 2 to 5 h with insulin, culminating with germinal vesicle breakdown. Pretreatment of oocytes with multiple protein synthesis inhibitors increased the level of basal activity, but did not greatly alter the time course of early activation of S6 kinase by insulin. In contrast, the later increase in S6 kinase activity was completely inhibited by pretreatment with cycloheximide. However, near maximal increases in S6 kinase activity occurred following injection of maturation-promoting factor, even in the presence of multiple protein synthesis inhibitors. Brief exposure to cycloheximide after 30 min or more of insulin stimulation increased the magnitude of insulin-stimulated activity without changing the overall pattern of activity increase. These results suggest that a rapidly turning-over inhibitor of S6 kinase exists, and the activation of S6 kinase by insulin occurs by protein synthesis-dependent and -independent mechanisms.