翻译核糖体和RNA聚合酶在转录延长中的合作
Sergey Proshkin1, A Rachid Rahmouni, Alexander Mironov
1Department of Biochemistry, New York University School of Medicine, New York, NY 10016, USA.
概括
细菌的翻译速度通过影响RNA聚合酶 (RNAP) 延长直接控制转录速率. 核糖体防止RNAP回溯,协调基因表达与细胞需求.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 细菌转录和翻译是合的过程.
- RNA聚合酶 (RNAP) 合成RNA,然后进行核糖体介导的翻译.
- 基因表达需要这两个过程之间的协调.
研究的目的:
- 研究细菌中转录和翻译之间的调控关系.
- 为了确定转化速率如何影响RNAP延长速度.
- 阐明核糖体影响RNAP活动的机制.
主要方法:
- 在体内测量转录和翻译动态.
- 对罕见代码子含量的基因序列的分析.
- 核糖体进展和RNAP速度之间的相关性研究.
主要成果:
- 细菌转录延长率受到翻译速度的严格控制.
- 核糖体加速/减速直接影响RNAP的速度.
- 罕见的编码子与转录速率相反相关.
- 核糖体防止RNAP回溯,增强转录速度和阅读速度.
结论:
- 一种合作机制在细菌中结合了转录和翻译.
- 核糖体在调节RNAP活动和基因表达方面发挥着至关重要的作用.
- 这种协调确保了转录输出匹配跨基因和条件的转化需求.
相关概念视频
Transcription Elongation Factors
Transcription elongation is a dynamic process that alters depending upon the sequence heterogeneity of the DNA being transcribed. Hence, it is not surprising that the elongation complex's composition also varies along the way while transcribing a gene.
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
Transcription Elongation Factors
Transcription elongation is a dynamic process that alters depending upon the sequence heterogeneity of the DNA being transcribed. Hence, it is not surprising that the elongation complex's composition also varies along the way while transcribing a gene.
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
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The promoters and enhancers and their accessory proteins allow tight regulation of...
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RNA polymerase (RNAP) carries out DNA-dependent RNA synthesis in both bacteria and eukaryotes. Bacteria do not have a membrane-bound nucleus. So, transcription and translation occur simultaneously, on the same DNA template.
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
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Base complementarity between the three base pairs of mRNA codon and the tRNA anticodon is not a failsafe mechanism. Inaccuracies can range from a single mismatch to no correct base pairing at all. The free energy difference between the correct and nearly correct base pairs can be as small as 3 kcal/ mol. With complementarity being the only proofreading step, the estimated error frequency would be one wrong amino acid in every 100 amino acids incorporated. However, error frequencies observed in...


