Acetylation represses the binding of CheY to its target proteins
Acetylation represses the binding of CheY to its target proteins
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DOI：
10.1111/j.1365-2958.2010.07148.x
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发表时间：
2010-05-01
影响因子：
3.6
通讯作者：
Eisenbach, Michael
中科院分区：
文献类型：
--
作者：
Liarzi, Orna;Barak, Rina;Eisenbach, Michael
细菌趋化性的反应调节因子CheY产生顺时针旋转的能力受两种共价修饰-磷酸化和乙酰化的调节。虽然前者的功能和信号传播被广泛理解，但后者的机制和作用仍然不清楚。为了获得关于这种乙酰化的功能的信息，我们将CheY非酶促乙酰化至与体内发现的水平相似的水平，并检查其与其激酶CheA、磷酸酶CheZ和开关蛋白FliM（其在鞭毛开关复合物处的靶点）的结合。乙酰化抑制了与所有三种蛋白质的结合。这些结果表明，磷酸化和乙酰化决定了CheY与其靶蛋白结合的能力，从而提供了两种水平的调节，分别为快速和缓慢。快速水平由环境信号（例如趋化性和趋热性刺激）调节。慢的一个受细胞代谢状态的调节，它决定了在每个代谢状态下，可以参与信号传导的CheY分子的比例。
P>The ability of CheY, the response regulator of bacterial chemotaxis, to generate clockwise rotation is regulated by two covalent modifications - phosphorylation and acetylation. While the function and signal propagation of the former are widely understood, the mechanism and role of the latter are still obscure. To obtain information on the function of this acetylation, we non-enzymatically acetylated CheY to a level similar to that found in vivo, and examined its binding to its kinase CheA, its phosphatase CheZ and the switch protein FliM - its target at the flagellar switch complex. Acetylation repressed the binding to all three proteins. These results suggest that both phosphorylation and acetylation determine CheY's ability to bind to its target proteins, thus providing two levels of regulation, fast and slow respectively. The fast level is modulated by environmental signals (e.g. chemotactic and thermotactic stimuli). The slow one is regulated by the metabolic state of the cell and it determines, at each metabolic state, the fraction of CheY molecules that can participate in signalling.