氨酸酸盐的Riboswitch受到了Escherichia coli中氨酸衍生代谢转化产品的影响
Shirin Jahangirnejad1, Jean-Philippe Côté1, Daniel A Lafontaine1
1Department of Biology, Faculty of Science, RNA Group, Université de Sherbrooke, Sherbrooke, Quebec, Canada, J1K 2R1.
Journal of molecular biology
|May 16, 2025
概括
氨酸水平可能会意外地影响大肠杆菌中的氨酸酸盐 (TPP) рибо开关,这表明这些基因调节者可能会检测到超出其特定代谢物位的更广泛的细胞应激.
科学领域:
- 分子生物学分子生物学
- 代谢调节 代谢调节 代谢调节
- 控制基因表达 控制基因表达
背景情况:
- 带状切换器是调节基因表达的基因元素,以响应特定的代谢物结合.
- 虽然 рибо开关的特异性很高,但它们与更广泛的代谢途径的相互作用仍未得到充分研究.
- 了解细胞代谢转化如何影响 рибо开关功能对于理解基因调节至关重要.
研究的目的:
- 为了研究 lysine-sensing 和 thiamin pyrophosphate (TPP) -sensing riboswitches 在大肠杆菌中的调节机制.
- 为了确定非同源代谢物或它们的代谢副产品是否影响 рибо开关活动.
- 探索氨酸和TPP代谢途径之间的潜在交叉对话,影响 рибо开关功能.
主要方法:
- 在大肠杆菌中 lysine 和 TPP рибо开关调节的表征.
- 对在生长介质中添加 lysine 和 TPP 后基因表达变化的分析.
- 利用基约收藏中的突变菌株来探测代谢依赖性.
主要成果:
- 氨酸和TPP的添加都降低了它们各自的核糖开关调节的mRNA水平.
- 氨酸的添加也显著降低了TPP调节的mRNA,这表明对TPP рибо开关有间接影响.
- 这种间接效应在改变了氨酸降解的突变物中被废除了,这表明氨酸催化剂在TPP合成中发挥了作用.
- 添加TPP并没有影响 lysine riboswitch调节.
结论:
- 氨酸降解产物可能参与TPP生物合成,将氨酸代谢与TPP рибо开关活性联系起来.
- TPP 核子开关可以感知 lysine 水平的变化,这表明它在检测细胞压力方面发挥了更广泛的作用.
- 带状交换机可能表现出超出其直接代谢物标的细胞条件的敏感性.
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