通过与之相关的RCK蛋白TrkA对TrkH离子通道进行加
Yu Cao1, Yaping Pan, Hua Huang
1Department of Physiology & Cellular Biophysics, College of Physicians and Surgeons, Columbia University, 630 West 168th Street, New York, New York 10032, USA.
Nature
|April 20, 2013
概括
这项研究表明,细菌运输体TrkH表现出单通道活性,通过其相关蛋白TrkA通过ATP进行调节. 这些发现阐明了一种新的ATP介导的TrkH活性上调的机制.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- TrkH是一种K(+) 运输蛋白,在低环境中对细菌生长至关重要.
- TrkH与K(+) 频道具有结构上的相似性,但具有潜在的独特封闭机制.
- TrkH与TrkA一起作用,TrkA是一种含有RCK域的蛋白质,它调节K(+) 道关口.
研究的目的:
- 为了研究TrkH的离子通道活性.
- 为了确定TrkA在TrkH功能中的监管作用.
- 阐明ATP调节TrkH活动的机制.
主要方法:
- 单通道电生理学来评估TrkH活动.
- 进行X射线晶体学以确定TrkA和TrkA-TrkH复合物的结构.
- 生物化学试验分析蛋白质相互作用和构造变化.
主要成果:
- 证实了TrkH的单通道活动.
- 表明ATP与TrkA结合起来对TrkH活动进行上调.
- 解决了四度环TrkA环的两个不同的构造,既与TrkH孤立,又与TrkH复合.
结论:
- TrkH 作为一个受调节的离子通道.
- ATP与TrkA结合会诱导形状变化,导致TrkH活性增加.
- 这提供了对细菌运输的ATP依赖调节的机理洞察.
相关概念视频
Enzyme-linked Receptors
Enzyme-linked receptors are proteins that act as both receptor and enzyme, activating multiple intracellular signals. This is a large group of receptors that include the receptor tyrosine kinase (RTK) family. Many growth factors and hormones bind to and activate the RTKs.
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When a ligand binds to a cell-surface receptor, the receptor's intracellular domain changes shape, which may either activate its enzyme function or allow its binding to other molecules. The initial signal is amplified by most signal transduction pathways. This means that a single ligand molecule can activate multiple molecules of a downstream target. Proteins that relay a signal are most commonly phosphorylated at one or more sites, activating or inactivating the protein. Kinases catalyze the...


