转录因子CdnL的调节促进了Caulobacter对营养应激的适应
Erika L Smith1, Gaël Panis2, Selamawit Abi Woldemeskel1
1Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
PNAS nexus
|April 23, 2024
概括
细菌通过严格反应 (SR) 途径在营养压力期间清除CdnL蛋白. 这种蛋白质清除,与其他SR因素一起,对于细菌的生存和适应不断变化的营养可用性至关重要.
科学领域:
- 细菌应激反应的细菌应激反应
- 分子微生物学分子微生物学
- 基因调节 基因调节
背景情况:
- 细菌在营养缺乏期间激活严格反应 (SR),以调节基因表达.
- 由SpotT合成的二次信使 (p)ppGpp) 是SR的关键调解者,影响RNA聚合酶 (RNAP) 的转录和调节合成基因.
- CdnL是控制*Caulobacter crescentus*中合成基因的关键转录因子,但在SR期间其调节是未知的.
研究的目的:
- 调查转录因子CdnL在*Caulobacter crescentus*中严格反应 (SR) 期间的调节和功能重要性.
- 阐明CdnL翻译后修饰在细菌适应营养压力的作用.
主要方法:
- 在饥饿期间使用SpotT依赖性和ClpXP蛋白酶依赖性试验研究了CdnL下调.
- 分析了人工稳定CdnL在饥饿期间对核糖体和代谢基因表达的影响.
- 在波动的营养条件下,评估了野生类型细胞与CdnL未清除细胞的竞争能力.
主要成果:
- 在饥饿期间,CdnL以SpotT和ClpXP蛋白酶依赖的方式在翻译后下调.
- 在饥饿期间稳定CdnL会导致核糖体和代谢基因的错误调节.
- 在饥饿期间无法清除CdnL的细胞在受到营养物质波动时被野生类型细胞超越.
结论:
- 在SR期间通过SpoT和ClpXP调解的CdnL清除对于细菌的生存和适应营养应激是必不可少的.
- SR转录调节器和CdnL降解的联合作用允许快速适应营养补充.
- 对CdnL的翻译后调节对于在营养应激期间改变转录组至关重要,确保细胞存活.
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