从RelA/SpoT同类的机理和进化视角来看,从严格响应信号传输到超越严格响应信号传输
Tatsuaki Kurata1,2, Hiraku Takada2,3
1RNA Systems Biochemistry Laboratory, RIKEN Pioneering Research Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Bioscience, biotechnology, and biochemistry
|January 9, 2026
概括
细菌使用由警报器 (p) pGpp介导的严格反应来适应压力. 本综述详细介绍了RelA/SpoT同类酶 (RSH) 如何合成和水解警报子,影响细菌的转录,翻译和新陈代谢.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 细菌生理学 细菌生理学
背景情况:
- 严格的反应是一个关键的细菌应激适应机制.
- 警示剂,主要是瓜诺辛多酸盐 (p) pGpp,调节基因表达,转化和新陈代谢.
- RelA/SpoT同类酶 (RSH) 是 (p) pGpp合成和水解的核心.
研究的目的:
- 审查细菌中警报激素信号的机械,生理和进化方面.
- 探索RelA/SpoT同类 (RSH) 酶的各种功能.
- 讨论激素信号通路的进化起源和多样化.
主要方法:
- 关于细菌严格反应的机械学,生理学和进化学研究的文献综述.
- 分析长RSH和小警报激素合成酶/水解酶 (SAS/SAH) 的结构和功能.
- 对RSH酶的比较基因组学和进化轨迹分析.
主要成果:
- 激素的合成是以核糖体为中心的,由RelA和双功能Rel酶被饥饿的核糖体激活.
- 小型警报激素合成酶 (SAS) 产生各种警报,包括像 (p) pppApp.App.这样的腺激素警报.
- 毒性SAS (toxSAS) 模块具有独特的功能,例如tRNA 3'-CCA末端酸化.
- 进化分析揭示了从操作子到融合的RSH的轨迹,在toxSAS中可能会独立获取图案.
结论:
- RSH酶表现出不同的激活机制和功能输出,包括非正规的警报和tRNA修改.
- RSH酶的进化显示了从简单的操作子到复杂的融合蛋白质的适应.
- 了解警报激素信号提供了细菌应激反应和潜在的治疗点的见解.
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