压力激活的蛋白质激酶子家族的c-Jun激酶
J M Kyriakis1, P Banerjee, E Nikolakaki
1Diabetes Research Laboratory, Medical Services, Massachusetts General Hospital East, Charlestown 02129.
Nature
|May 12, 1994
概括
压力激活蛋白激酶 (SAPKs) 是一种新的MAP激酶类. 这些激酶被细胞压力和瘤亡因子-α激活,调节c-Jun活动.
科学领域:
- 细胞信号通道是细胞信号通道.
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 线素激活蛋白 (MAP) 激酶Erk-1和Erk-2是通过氨酸和三氨酸酸化激活的林导向激酶.
- 类酶p54,类似于Erks-1/2,是以proline为导向的,需要Tyr和Ser/Thr酸化才能活性.
- p54表现出明显的基质特异性,比pp90rsk.sk.更活跃地酸化c-Jun事务激活域.
研究的目的:
- 描述p54激酶及其细胞外调节激酶子家族.
- 调查涉及p54.4的激活机制和信号通路.
- 确定p54在细胞应激反应和TNF-α信号传递中的作用.
主要方法:
- 分子克隆p54.4. 的分子克隆.
- 对激酶活性和基质特异性的分析.
- 通过mitogens,phorbol,细胞应激和瘤缩因子 (TNF) -alpha.alpha的激活的研究.
主要成果:
- 分子克隆揭示p54属于细胞外调节激酶的独特亚家族,被指定为应激激活蛋白激酶 (SAPKs).
- SAPKs与Erks-1/2相同的40-45%,但被mitogens或phorbol基激活不良.
- SAPKs是主要的c-Jun N-终端激酶,由细胞应激和TNF-alpha激活,也由基胺酶激活.
结论:
- SAPKs定义了一种由TNF-alpha和细胞压力激活的新信号通路.
- 这一途径可能是由基于基胺的第二信使启动的.
- 在应对压力时,SAPKs在调节c-Jun和TNF-alpha的活性方面发挥着至关重要的作用.
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