拉巴胺可以选择性地抑制p70 S6激酶的介质素-2激活
C J Kuo1, J Chung, D F Fiorentino
1Howard Hughes Medical Institute, Unit in Molecular and Genetic Medicine, Beckman Center, Stanford University School of Medicine, California 94305-5425.
Nature
|July 2, 1992
概括
宏类拉巴胺通过抑制p70 S6激酶激活来阻止细胞循环的进展. 这一发现揭示了调节T细胞增殖和免疫抑制的保存途径.
科学领域:
- 免疫学 免疫学 免疫学
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
背景情况:
- 拉巴素是一种宏类物质,阻止了酵母和哺乳动物细胞的细胞循环,这表明S阶段进入有保存的调节途径.
- 在哺乳动物中,拉巴胺通过阻断因特乐金-2受体诱导的S相进入来抑制T细胞增殖,从而导致免疫抑制.
研究的目的:
- 为了研究拉巴胺抑制介质素-2诱导的T细胞增殖的机制.
- 为了确定拉巴素在T细胞中准的特定信号通路.
主要方法:
- 研究了介素-2对p70 S6激酶,MAP激酶 (ERK) 和S6激酶 (RSK) 酸化和激活的作用.
- 评估了拉巴胺对因特鲁金-2诱导的p70 S6激酶激活的影响.
- 研究了拉帕米辛,FK506和FKBP之间的相互作用.
主要成果:
- 介质素-2可以选择性地刺激p70 S6激酶的酸化和激活,但不能刺激ERK或RSK.
- 拉巴胺素在低度 (0.05-0.2 nM) 时快速且完全抑制因特乐金-2-诱导的p70 S6激酶激活.
- FK506具有竞争性对抗拉帕素的作用,表明通过FKBP进行调解.
结论:
- 拉帕素-FKBP复合体选择性地阻断了p70 S6激酶激活级联.
- 这种信号通路与T细胞进入S阶段的调节有关.
- 拉巴胺的免疫抑制作用与抑制p70 S6激酶信号传递有关.
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