协同转录和翻译调节感应未充电的托tRNA
Guangnan Chen1, Charles Yanofsky
1Department of Biological Sciences, Stanford University, Stanford, CA 94305, USA.
Science (New York, N.Y.)
|July 12, 2003
概括
细菌细菌使用未充电的托转移RNA (tRNATrp) 来控制抗TRAP (AT) 蛋白质的合成. 这种双重调节通过调节转录终结来确保trp操作子的正确表达.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 基因规则 基因规则
背景情况:
- 在 Bacillus subtilis 中的 trp 操作子是由 trp RNA 结合衰减蛋白 (TRAP) 调节的.
- 在trp操作子领导者中转录终止是由抗TRAP (AT) 蛋白抑制的.
- 亚特蛋白的转录是由未充电的托转移RNA (tRNATrp) 激活的.
研究的目的:
- 通过未充电的tRNATrp来研究AT蛋白的翻译调节.
- 阐明未充电的tRNATrp控制AT合成的机制.
- 了解AT合成和TRAP介导的trp操作调节之间的相互作用.
主要方法:
- 在AT操作中对10个残余编码区域的分析.
- 研究连续的托编码子在翻译控制中的作用.
- 评估翻译完成/抑制对AT蛋白生产的影响.
主要成果:
- AT基因的翻译也由未充电的tRNATrp进行调节.
- 一个特定的编码序列,有三个连续的托编码子,在AT结构基因之前.
- 完成翻译会抑制AT合成,而不完整的翻译会增强AT生成.
结论:
- 细菌细菌采用一个双重感应机制,涉及未充电的tRNATrp来调节AT合成.
- 这种AT的双重调节 (转录和翻译) 可以确保对TRAP活动的精确控制.
- 对AT和TRAP的协调监管微调了trp操作子的表达,以响应托的可用性.
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