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Assaying Protein Kinase Activity with Radiolabeled ATP
Published on: May 26, 2017
对AMP激活蛋白激酶自身抑制机制的结构洞察力
Lei Chen1, Zhi-Hao Jiao, Li-Sha Zheng
1MOE Key Laboratory of Bioinformatics, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing 100084, China.
Nature
|May 29, 2009
概括
AMP激活蛋白激酶 (AMPK) 的活性由AMP结合来调节. 结构和生化研究揭示了自抑制域 (AID) 如何抑制AMPK,以及AMP结合如何激活它.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 细胞的新陈代谢
背景情况:
- AMP激活蛋白激酶 (AMPK) 通过感知ATP/AMP比率来调节细胞能量稳态.
- AMPK在细胞生长,增殖和极性中起着至关重要的作用,使其成为代谢疾病和癌症的关键药物标.
- 通过AMP结合来调节AMPK活动的确切机制一直是难以捉摸的.
研究的目的:
- 阐明AMPK自抑制和AMP激活的结构基础.
- 为了研究自身抑制域 (AID) 在调节激酶活性中的作用.
- 了解AMPK激活背后的构造变化.
主要方法:
- 使用X射线晶体学来确定非酸化AMPKα子单元片段 (KD-AID) 和酸化激酶域 (Snf1-pKD) 的结构.
- 进行了生物化学测定,包括体外动力学研究,以评估激酶活性和突变的影响.
- 使用结构分析来解释激酶域与自身抑制域之间的相互作用.
主要成果:
- 自抑制性域 (AID) 结合到酶域的链区域,限制链alphaC,从而显著降低酶活性.
- 干扰KD-AID接口取消了自身抑制,使AMPK突变物对AMP度变化没有反应.
- 证明AMP通过全性机制和通过抑制脱酸化来激活AMPK.
结论:
- 这项研究揭示了AMPK自抑制的主要机制,该机制由AID介导.
- 提出了一个由AMP激活AMPK的结构交换机模型,涉及自抑制的释放.
- 这些发现为AMPK调节和潜在的治疗策略提供了关键的见解.
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