感染相关的条件决定了Salmonella和cochaperones的差异和坐标表达
Carissa Chan1, Keiichiro Mukai1, Eduardo A Groisman1
1Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, Connecticut, USA.
mBio
|March 31, 2025
概括
沙门氏菌Typhimurium在饥饿期间差异地表达分子伴侣. 这种由PhoP调节的反应涉及增加DnaK,同时减少触发因子和J域cochaperones.
科学领域:
- 分子生物学分子生物学
- 细菌应激反应的细菌应激反应
- 蛋白质的平衡是蛋白质的平衡.
背景情况:
- 分子陪伴者对于维持细菌中的蛋白质平衡是必不可少的.
- 通常,像DnaK这样的辅助子与辅助子 (例如J域蛋白) 合作,用于蛋白质折叠.
- 病原细菌,如沙门氏菌 Typhimurium 面临各种压力条件,包括营养饥饿.
研究的目的:
- 为了研究沙门氏菌 Typhimurium 在细胞质Mg2+ 饥饿下如何调节沙门氏菌 chaperone 和 cochaperone 的表达.
- 确定PhoP调节器在这种差异性基因表达中的作用.
- 阐明DnaK在压力下影响自身转录的机制.
主要方法:
- 在Mg2+饥饿条件下,对护卫者 (dnaK, tig) 和辅助者 (dnaJ, djlA) 的基因表达 (mRNA水平) 的分析.
- 研究PhoP调节器在控制这些表达变化的作用.
- 对DnaK对RpoH及其依赖转录的反调节的评估.
主要成果:
- 在Mg2+饥饿期间,沙门氏菌Typhimurium在调节dnaKmRNA的同时调节tig,dnaJ和djlAmRNA的降低.
- 这种差异表达取决于主调节器PhoP,它调节ATP水平以稳定RpoH.
- DnaK对RpoH及其转录的负反独立于J域的cochaperones.
结论:
- 细菌可以根据特定的压力条件差异地表达伴侣和辅助伴侣,偏离坐标表达.
- 以PhoP为媒介的差异表达策略允许沙门氏菌在Mg2+饥饿期间优先考虑DnaK功能.
- 这突显出一种特定条件的调节机制,用于维持病原体中的蛋白质稳态.
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