复制-转录冲突产生R循环,调节细菌应激生存和发病
Kevin S Lang1, Ashley N Hall2, Christopher N Merrikh1
1Department of Microbiology, Health Sciences Building - J-wing, University of Washington, Seattle, WA, 98195.
Cell
|August 13, 2017
概括
正面转录碰撞导致R循环形成,阻断复制并增加突变. 通过解决这些R循环,RNase HIII活动对细菌的生存和发病至关重要.
科学领域:
- 分子生物学
- 遗传学
- 微生物学
背景情况:
- 复制转录碰撞会影响基因组的稳定性和进化.
- 头部转录,特别是从落后链基因,是独特的破坏复制,导致基因组不稳定.
- 这种干扰的根本机制尚不清楚.
研究的目的:
- 调查正面转录碰撞与R循环形成之间的联系.
- 确定R环在复制阻断,突变发生和基因表达中的作用.
- 阐明R-循环分解酶,如RNase HIII在细菌应激生存和发病过程中的重要性.
主要方法:
- 在Bacillus subtilis的正面碰撞地点研究R环形成.
- 评估R环形成对复制,突变和基因表达的影响.
- 研究了RNase HIII在应激生存和宿主感染中的作用.
主要成果:
- 发现正面碰撞会促进R环在Bacillus subtilis中的广泛形成.
- 在碰撞部位的普遍R循环完全抑制复制,增加突变发生,并抑制基因表达.
- 在碰撞区域的RNase HIII活性对于细菌的应激生存至关重要,特别是对正面应激反应基因.
- 由于许多毒性基因是面向的,RNase HIII的丧失显著损害了Listeria monocytogenes的毒性和宿主复制.
结论:
- 额头碰撞的有害影响主要是由于过度的R循环形成.
- 像RNase HIII这样的酶对R循环结构的分解对于细菌应激适应至关重要.
- 对于细菌病原体来说,R循环的分辨率是必不可少的,它会影响像Listeria monocytogenes这样的病原体的成功.
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