对c-Abl氨酸激酶自身抑制的结构基础
Bhushan Nagar1, Oliver Hantschel, Matthew A Young
1Howard Hughes Medical Institute and Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA.
Cell
|March 26, 2003
概括
慢性骨髓性白血病 (CML) 涉及c-Abl放松调节. c-Abl 1b的基化诱导自抑制,类似于Src激酶,解释了Gleevec的作用.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 在瘤学瘤学.
背景情况:
- c-Abl放松调控与慢性髓性白血病 (CML) 有关.
- c-Abl的自身抑制机制仍然不清楚,因为它缺乏在 Src 激酶中发现的特定的色胺残留物.
- 了解c-Abl调节对于CML治疗策略至关重要.
研究的目的:
- 为了阐明c-Abl. 的自身抑制机制.
- 调查c-Abl调节的结构基础及其对伊马替尼布的差异反应.
- 为了解c-Abl和c-Src激酶的不同行为提供见解.
主要方法:
- 对c-Abl.晶体结构的分析.
- 调查N-终端基化在c-Abl构成中的作用.
- 使用Src酶进行比较结构分析.
主要成果:
- c-Abl 1b的N端myristoyl修饰与激酶域结合,诱导结构变化.
- 这些变化促进了SH2和SH3域的对接,形成了自抑制状态.
- c-Abl的自身抑制结构与非活性Src酶有相似之处,但具有关键差异.
结论:
- 在c-Abl自身抑制过程中,基化非常重要.
- 结构上的差异解释了为什么伊马替尼 (Gleevec) 抑制了Abl,而不是Src.
- 这为向性CML治疗提供了分子基础.
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