含有托尔/介质素-1受体 (TIR) 域的蛋白质具有NAD-RNA分解活性
Xufeng Wang1,2,3, Dongli Yu4,5,6, Jiancheng Yu7
1State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Joint Center for Life Sciences, School of Life Sciences, Peking University, Beijing, 100871, China.
Nature communications
|March 14, 2024
概括
TIR域蛋白可以从NAD覆盖的RNA (NAD-RNA) 中去除尼古丁胺,产生循环ADPR-RNA. 细菌中的这种deNAMing活动表明TIR蛋白在调节基因表达中的作用.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 微生物学 微生物学
背景情况:
- 尼古丁胺胺氨基二核酸 (NAD+) 在各种生物体中充当非正规RNA盖.
- 涉及防御反应的TIR域含有蛋白质具有NADase活性.
研究的目的:
- 研究细菌和古生物学TIR域蛋白在NAD覆盖RNA (NAD-RNAs) 上的deNAMing活性.
- 阐明TIR域介导的NAD-RNA分解的酶机制和生物影响.
主要方法:
- 在体外的酶分析评估细菌和古老的TIR蛋白对NAD-RNAs的deNAMing活性.
- 剪切产品的特征,特别是周期性ADPR-RNA.
- 在大肠杆菌中Acinetobacter baumannii TIR (AbTir) 的异质表达,以评估体内对细胞传播和NAD-RNA水平的影响.
主要成果:
- 来自多种物种的TIR域蛋白有效地从NAD-RNA中去除尼古丁胺胺 (NAM) 部分.
- AbTir的deNAMing活动产生循环ADPR-RNA,随后被已知的酶切割.
- 野生型AbTir的表达,但不是催化突变,在大肠杆菌中抑制了细胞生长和降低了特定的NAD-RNA水平.
结论:
- 含有TIR域的蛋白质作为NAD-RNAs的deNAMing酶起作用.
- 这种活动表明,由TIR域蛋白调节基因表达的新机制.
- 这些发现为了解核糖核酸代谢和原核细胞的防御机制开辟了新的途径.
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