一个一般的RNA模板RNA延伸活性E. 大肠杆菌的RNA聚合酶
Drew Galls1,2, Andreas U Mueller3, Emily Greenwald4,2
1Department of Genetics, Stanford University, Stanford, California 94305, USA dgalls@stanford.edu afire@stanford.edu.
概括
多子单元RNA聚合酶 (RNAP) 可以从RNA模板中合成RNA,这对于RNA病原体和基因调节至关重要. 这项研究揭示了这种RNA模板RNA扩展活性在Escherichia coli RNAP中的一般机制.
科学领域:
- 分子生物学分子生物学
- 病毒学 病毒学
- 生物化学 生物化学
背景情况:
- 多子单元DNA依赖的RNA聚合酶 (RNAPs) 具有非正规的RNA指导的RNA合成活性.
- 这种活动对RNA病原体,如型肝炎三角病毒 (HDV) 和细胞基因调控具有重要意义.
- 基于RNAPRNA模板RNA合成的精确机制仍然不完全理解.
研究的目的:
- 为了阐明使用大肠杆菌RNAP作为模型的多子单元RNA聚合酶的一般RNA模板RNA扩展活性.
- 研究RNAP从RNA模板中合成RNA的机制.
主要方法:
- 利用大肠杆菌RNAP作为一个模型系统.
- 使用各种RNA模板进行RNA模板RNA延伸试验.
- 分析了分子内原料的形成:模板复合体.
主要成果:
- 证明RNA模板的3'端可以向后折叠,形成一个短 (1-2个基对) 内部分子复合体,与上游模板基.
- 表明RNAP扩展了这种分子内复合体,合成了互补的RNA.
- 观察到RNA模板RNA延伸是一个快速的过程 (几分钟),并且通常发生在大多数RNA模板中,无论DNA模板如何.
结论:
- 定义了细胞RNAP的一般RNA模板RNA延伸活性.
- 如果不受管制,这种活动可能会促进基于RNA的病原体 (例如HDV,病毒) 的出现和复制.
- 相反,受管制的活动可能会限制这些RNA元素.
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