通过对KSR蛋白的异质控制,MEK驱动BRAF激活
Hugo Lavoie1, Malha Sahmi1, Pierre Maisonneuve2
1Institute for Research in Immunology and Cancer Laboratory of Intracellular Signaling Université de Montréal C.P. 6128, Succursale Centre-Ville Montréal, Québec H3C 3J7, Canada.
Nature
|February 13, 2018
概括
RAF激酶在癌症中至关重要, 但它们的二元化阻碍了药物开发. 这项研究揭示了BRAF和KSR1之间的新相互作用,揭示了RAF激酶激活和挑战KSR的新机制.
科学领域:
- 分子生物学
- 癌症研究
- 信号传输
背景情况:
- RAF家族的激酶 (ARAF,BRAF,CRAF) 和伪激酶 (KSR1,KSR2) 在癌症中起着关键作用.
- RAF激酶的激活取决于二分化,这是药物开发的一个挑战.
- 据认为KSR伪基因酶是RAF和MEK的支架,但它们的二分化调节尚不清楚.
研究的目的:
- 阐明与RAF家族成员的KSR伪激酶二分化相关的监管原则.
- 确定介导BRAF-KSR1异构的特定分子相互作用.
- 了解KSR-MEK复合体如何影响BRAF的催化活性.
主要方法:
- 通过生物化学测试研究了蛋白质与蛋白质的相互作用.
- 确定了参与RAF-KSR1复合体形成的新型蛋白质域.
- 通过KSR1- MEK复合体对BRAF激酶活性进行全调节.
主要成果:
- 发现BRAF和KSR1的异构化是由N端相互作用介导的,包括BRAF的BRS域和KSR1的CC-SAM域.
- 表明MEK与KSR1的激酶域结合驱动了BRAF-KSR1的异构化.
- 证明KSR-MEK复合物可以以异质方式刺激BRAF的催化活性.
结论:
- 通过特定的N端接触和MEK结合来调节BRAF-KSR1异构.
- KSR-MEK复合体以基方式激活BRAF,从而挑战KSR仅在支架上的作用.
- 这些发现为RAF激酶调节和潜在的癌症治疗策略提供了新的见解.
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