激活蛋白激酶C会降低c-Jun的酸化,这些酸化发生在那些负面调节其DNA结合活动的部位
W J Boyle1, T Smeal, L H Defize
1Molecular Biology and Virology Laboratory, Salk Institute, La Jolla, California 92037.
Cell
|February 8, 1991
概括
在静止细胞中,c-Jun蛋白因酸化而不活跃. 蛋白激酶C的激活触发了脱酸化,增强了AP-1结合活性和c-Jun.
科学领域:
- 分子生物学分子生物学
- 细胞信号传递 细胞信号传递
背景情况:
- c-Jun是一种调节基因表达的转录因子.
- 酸化c-Jun会影响其DNA结合和转激活活动.
研究的目的:
- 调查c-Jun酸化在调节其活动中的作用.
- 确定特定的酸化位点及其对DNA结合的影响.
主要方法:
- 在实验室中使用糖原合成酶激酶3 (GSK-3) 进行酸化试验.
- 在c-Jun酸化位点的位点定向突变发生.
- 在蛋白激酶C激活后对AP-1结合活性的分析.
主要成果:
- 在三个特定地点 (残留物227-252) 发现GSK-3酸化物c-Jun.
- 蛋白激酶C的激活会导致c-Jun的脱,增加AP-1的结合.
- 氨酸243转化为氨酸的突变使c-Jun的转激活增加了10倍.
结论:
- 在休息细胞中,c-Jun存在于潜伏的酸化状态.
- 由蛋白激酶C触发的局部特异性脱化,激活了c-Jun.
- 酸化状态是c-Jun的转录功能的一个关键调节者.
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