综合方法揭示了对细菌翻译延长的监管控制
Arvind R Subramaniam1, Brian M Zid1, Erin K O'Shea2
1Faculty of Arts and Sciences Center for Systems Biology, Harvard University, Cambridge, MA 02138, USA; Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA.
Cell
|November 24, 2014
概括
在翻译过程中,核糖体延长率会有所变化. 这项研究表明,氨基酸化动力学和翻译流产调节蛋白质合成,特别是在大肠杆菌中营养应激期间.
科学领域:
- 分子生物学分子生物学
- 系统生物学 系统生物学
- 计算生物学 计算生物学
背景情况:
- 在翻译过程中,核糖体延长率不均.
- 理论模型和实验数据之间存在差异,这些差异涉及体内延长率的决定因素及其对蛋白质水平的影响.
研究的目的:
- 解决有关翻译延长率决定因素和机制的冲突.
- 为了研究延长速度对蛋白质水平的影响.
- 开发一个全细胞转化模型在大肠杆菌.
主要方法:
- 在各种条件下测量了转录组范围内的核糖体占用率.
- 在大肠杆菌中制定了一个全细胞翻译模型.
- 在饥饿期间分析了延长暂停对tRNA氨基化动态的敏感性.
主要成果:
- 在营养丰富的生长过程中,大多数编码子的延长率不受氨基酸-tRNA度的限制.
- 在氨基酸饥饿期间的延长暂停对tRNA氨基化动力学敏感.
- 停顿时的翻译堕胎解释了饥饿期间的核糖体占用.
- 堕胎减少了全球蛋白质合成,但增强了特定mRNAs的翻译.
结论:
- 氨基化和堕胎在压力期间起着调节作用.
- 这项研究为建模翻译提供了一个实验限制的框架.
- 不均的核糖体延长率受到营养的可用性和tRNA动态的影响.
相关概念视频
Translational Regulation
890
Translational regulation in prokaryotes ensures efficient protein synthesis by controlling ribosome access to mRNA. This regulation is mediated by secondary RNA structures, including translational riboswitches, RNA thermometers, and small RNAs (sRNAs), which respond to intracellular and environmental signals to modulate gene expression.Translational RiboswitchesRiboswitches in the leader region of mRNAs can regulate translation by altering the accessibility of the Shine-Dalgarno (SD) sequence,...
890
Coordination of Gene Expression Processes in Bacteria
1.0K
The DNA replication, transcription, and translation processes are intricately coupled in bacteria, allowing efficient gene expression and rapid protein synthesis. While this physical and functional coordination is advantageous, it introduces challenges that bacteria overcome through specific regulatory mechanisms.Coupling of Replication, Transcription, and TranslationThe coupling of replication, transcription, and translation is a hallmark of bacterial gene expression. As the replisome unwinds...
1.0K
Regulation of Expression at Multiple Steps
1.6K
The gene expression in cells is regulated at different stages: (i) transcription, (ii) RNA processing, (iii) RNA localization, and (iv) translation. Transcriptional regulation is mediated by regulatory proteins such as transcription factors, activators, or repressors—these control gene expression by initiating or inhibiting the transcription of genes. Once a precursor or pre-mRNA is produced, it undergoes post-transcriptional modification, including 5' capping, splicing, and the...
1.6K
Regulation of Expression Occurs at Multiple Steps
27.5K
Gene expression can be regulated at almost every step from gene to protein. Transcription is the step that is most commonly regulated. This involves the binding of proteins to short regulatory sequences on the DNA. This association can either promote or inhibit the transcription of a gene associated with the respective sequence.
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
27.5K
Regulation of Expression Occurs at Multiple Steps
4.4K
4.4K
Initiation of Translation
40.8K
Initiating translation is complex because it involves multiple molecules. Initiator tRNA, ribosomal subunits, and eukaryotic initiation factors (eIFs) are all required to assemble on the initiation codon of mRNA. This process consists of several steps that are mediated by different eIFs.
First, the initiator tRNA must be selected from the pool of elongator tRNAs by eukaryotic initiation factor 2 (eIF2). The initiator tRNA (Met-tRNAi) has conserved sequence elements including modified bases at...
First, the initiator tRNA must be selected from the pool of elongator tRNAs by eukaryotic initiation factor 2 (eIF2). The initiator tRNA (Met-tRNAi) has conserved sequence elements including modified bases at...
40.8K


