一个RNA螺旋酶细菌转录终端的DNA结合
Sriyans Jain1, Abhijeet Behera1,2, Ranjan Sen1
1Laboratory of Transcription, Centre for DNA Fingerprinting and Diagnostics, Inner Ring Road, Uppal, Hyderabad, 500039, India.
The Biochemical journal
|January 6, 2025
概括
细菌的Rho转录终结器结合了DNA和RNA,影响了转录. 不活跃的Rho六基体可以使用细菌染色体作为休息表面,以防止意外的转录终止.
科学领域:
- 分子生物学分子生物学
- 细菌的转录 细菌的转录
- 蛋白质-DNA相互作用
背景情况:
- 罗转录终结体是一个六次性ATP依赖的RNA旋酶,对于移除延长型RNA聚合酶至关重要.
- 罗具有不同的RNA结合部位:一个主要结合部位 (PBS) 和一个中枢通道中的二次结合部位 (SBS).
研究的目的:
- 研究Rho与双链DNA (dsDNA) 的相互作用及其功能影响.
- 探索细菌细胞内Rho六合体的局部化和潜在的休息机制.
主要方法:
- 在体外转录试验测试以评估Rho对转录终止的影响.
- 生物化学实验分析Rho与dsDNA和单链DNA (ssDNA) 的结合亲和关系.
- 显微镜技术可视化不同生长阶段在细菌细胞中的Rho定位.
主要成果:
- 罗通过其PBS与线性dsDNA和圆形等离子体无特异地结合,这种相互作用与ssDNA相竞争.
- 长期的dsDNA与PBS结合激活了Rho在SBS中的ATPase活性,而预先结合的Rho与dsDNA则抑制了转录终结效率.
- 较高的Rho度降低了体外转录,这表明潜在的抑制作用.
- 罗定位从细胞极/细胞膜中部日志阶段转移到静止阶段的细菌染色体,可能处于超寡合状态.
结论:
- 罗与dsDNA相互作用,影响其转录终止活性,并可能作为基因表达抑制剂.
- 细菌染色体可以作为不活跃的Rho六合体的"休息表面",防止过早的转录终止.
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