CASK 作为Mg2+独立的神经素激酶的功能
Konark Mukherjee1, Manu Sharma, Henning Urlaub
1Department of Neuroscience, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390-9111, USA. konark.mukherjee@utsouthwestern.edu
Cell
|April 22, 2008
概括
/卡尔莫杜林依赖的血清蛋白激酶 (CASK) 作为无的活性激酶起作用,挑战其伪激酶的分类. 这一发现揭示了CASK.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 神经科学是一个神经科学.
背景情况:
- CASK是一种MAGUK蛋白质,具有独特的N终端CaM-激酶域.
- 由于缺乏Mg2+结合的DFG基因,这个域被认为是催化不活的 (伪基因酶).
研究的目的:
- 为了研究CASK CaM-激酶域的催化活性.
- 阐明其酶功能的结构基础,如果有的话.
主要方法:
- 高分辨率的晶体结构确定CASK CaM-激酶域.
- 生物化学测试以评估激酶活性 (ATP结合和转移).
主要成果:
- CASK CaM-激酶域具有构成性活性,结合ATP并催化无Mg2+的转移体.
- CASK自化和化其相互作用体,神经素-1.
- 结构数据显示了一个活性构造,使Mg2+独立的催化.
结论:
- CASK具有不寻常的,Mg2+独立的激酶活性,补充其支架功能.
- 这挑战了伪基因酶的分类,并表明其他伪基因酶也可能活跃.
- 通过其脚手架领域招募的CASK酸化基质.
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