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Assaying Protein Kinase Activity with Radiolabeled ATP
Published on: May 26, 2017
通过双酸化来激活MAP激酶ERK2的激活机制
B J Canagarajah1, A Khokhlatchev, M H Cobb
1Department of Biochemistry, The University of Texas Southwestern Medical Center at Dallas, 75235-9050, USA.
Cell
|September 23, 1997
概括
线素激活蛋白 (MAP) 激酶ERK2的活性形式揭示了酸化如何激活酶. 激活唇和特异性口袋的关键结构变化解释了ERK2的存在.
科学领域:
- 生物化学和结构生物学.
- 酶学 是一种酶学.
- 信号传导途径的信号传导途径.
背景情况:
- 线素激活蛋白 (MAP) 激酶,特别是ERK2,是细胞过程的关键调节者.
- 了解ERK2激活的结构基础对于破译信号传导至关重要.
- 之前的研究表明,ERK2功能中的激活唇内含有酸化.
研究的目的:
- 阐明ERK2.2的活性,双化形式的三维结构.
- 确定导致ERK2激活的特定形状变化.
- 确定ERK2.2的林导向基质特异性的分子基础.
主要方法:
- 使用X射线结晶学来确定活性ERK2.2的结构.
- 与其他激酶进行了比较结构分析,包括CDK2-CyclinA.
- 分析的重点是激活唇和周围区域内的形状变化.
主要成果:
- 活性结构显示了激活唇的重新折叠,使索氨酸和索氨酸与结合部位对齐.
- 在P+1位点,MAP激酶插入,C端延伸和C螺旋中观察到显著的构造变化.
- 确定了以proline为导向的P+1特异性口袋的重塑及其与CDK2-CyclinA的相似性是关键的激活机制.
结论:
- ERK2激活涉及协调的结构重组,特别是在激活唇和特异性口袋.
- 这项研究定义了ERK2.2中proline导向特异性的结构基础.
- 酸化状态与其他细胞组成部分的全性传播是由激活唇外的构造变化促进的.
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