李斯特菌的转录景观从萨普罗菲特主义到毒性
Alejandro Toledo-Arana1, Olivier Dussurget, Georgios Nikitas
1Institut Pasteur, Unité des Interactions Bactéries-Cellules, F-75015 Paris, France.
Nature
|May 19, 2009
概括
这项研究揭示了Listeria monocytogenes如何通过分析其整个基因组转录从环境生存过渡到引起感染. 它揭示了对细菌病原和病毒性基因表达至关重要的新型RNA调节体.
科学领域:
- 微生物学 微生物学
- 基因组学就是基因组学.
- 分子生物学分子生物学
背景情况:
- 李斯特菌 (Listeria monocytogenes) 是一种环境细菌,会导致严重的食物传播疾病.
- 它从一个saprophyte到一个病原体的过渡是不太了解.
- 它越来越多地被用作研究病变发生的模型生物.
研究的目的:
- 为了全面分析Listeria monocytogenes的转录景观.
- 确定管理转向致病性状态的新型监管机制.
- 为了绘制完整的操作子结构和多样化的RNA物种.
主要方法:
- 整个基因组片阵列被用来分析来自野生类型和突变细菌的RNA.
- 细菌转录在体外,体外和体内条件下进行了研究.
- 进行了与无垢菌 (Listeria innocua) 的比较分析.
主要成果:
- 建立了一个完整的Listeria操作图,揭示了广泛的RNA多样性.
- 确定了50多个小RNA,反意义RNA和重叠的未翻译区域.
- 证实了SigB和PrfA是不同宿主环境中毒性基因的关键调节者.
- 发现了与病毒性基因表达相关的新型非编码RNA.
结论:
- 在宿主感染期间,Listeria monocytogenes经历了显著的转录重编程.
- 涉及多种RNA物种的以前未知的调节机制控制细菌病变.
- 特定的非编码RNA与毒性有关,并且在非致病性亲属中不存在.
相关概念视频
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