在Bacillus subtilis中功能性脱离的转录-翻译
Grace E Johnson1, Jean-Benoît Lalanne1,2, Michelle L Peters1
1Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA.
Nature
|August 28, 2020
概括
在细菌中,转录和翻译并非普遍存在. 在Bacillus subtilis中,RNA聚合酶 (RNAP) 超过核糖体,导致
科学领域:
- 分子生物学
- 基因组学
- 微生物生理学
背景情况:
- 转录-翻译合传统上被视为细菌基因表达的标志.
- 这种合涉及RNA聚合酶 (RNAP) 和核糖体协调基因表达和调节.
- 在多种细菌物种中这种结合的普遍性仍然在很大程度上未被探索.
研究的目的:
- 调查转录-翻译合是否是所有细菌的基本特征.
- 探索 Bacillus subtilis 等模型生物中未结合的转录和翻译的含义.
- 鉴定 prokaryotes 中的替代基因表达模式及其调节机制.
主要方法:
- 在 Bacillus subtilis 中对RNAP和核糖体动态进行比较分析.
- 在非合系统中研究RNA监控和转化控制机制.
- 基因组分析以确定跨细菌族的"逃跑转录"的签名.
主要成果:
- 在 Bacillus subtilis 中,RNAP 超过了核糖体,证明了"逃跑转录".
- 不结合的转录解释了对Rho-依赖终结的依赖性降低以及对核糖突变和RNA结合蛋白的使用增加.
- 脱离转录的基因组特征在多种细菌系中广泛存在.
结论:
- 结合RNAP-核糖体运动不是细菌基因表达的一般特征.
- 细菌使用至少两种主要的基因表达方式:转化合和失控转录.
- 这些不同的模式决定了 prokaryotes 中的基因组特异性调节策略.
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