转录后的封闭产生共酶A结合RNA
Krishna Sapkota1, Jordyn K Lucas2,3, Jarrett W Faulkner1
1Department of Chemistry and Biochemistry, University of Southern Mississippi, Hattiesburg, MS, USA.
RNA biology
|November 30, 2023
概括
研究人员发现,酸盐氨酸腺转移酶 (PPAT) 可以在转录后将RNA与4-酸盐氨酸封闭,形成CoA-RNA. 这表明了细菌中CoA-RNA生物发生的新途径.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 在RNA生物学,RNA生物学.
背景情况:
- NAD可以通过共同转录的方式被纳入RNA.
- 由于3'-dephospho-CoA (dpCoA) 水平较低,通过这种机制不太可能形成与CoA相关的RNA.
- 需要一个对CoA-RNA生物发生的后转录机制.
研究的目的:
- 调查酸丁氨基基转移酶 (PPAT) 是否可以形成CoA-RNA.
- 确定PPAT作为基质所需的RNA特征.
- 确定PPAT介导RNA封闭的机制和调节.
主要方法:
- 在实验室中使用合成RNA对PPAT活性进行表征.
- 对RNA 5'终端和酶抑制剂的突变分析.
- 在候选RNAs的细菌表达之后的CoA-RNA捕获Seq.
主要成果:
- PPAT在转录后将4'-酸盐氨酸转移到RNA5'末端,形成CoA-RNA.
- 在5'终端有4-10个未配对核酸的RNA是首选基质.
- ATP 抑制了 PPAT 的活性,而 PPAT 的结合则不那么依赖特定的 5' 核酸.
- 在体内实验支持PPAT介导的RNA转录的CoA封闭.
结论:
- PPAT促进了转录后RNA封闭,产生了CoA-RNA.
- 这代表了细菌中CoA-RNA生物发生的新机制.
- RNA结构,特别是5'终端,影响PPAT基质识别.
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