促进器架构决定了基因表达的细胞间变异性
Daniel L Jones1, Robert C Brewster2, Rob Phillips3
1Department of Applied Physics, California Institute of Technology, Pasadena, CA 91125, USA.
Science (New York, N.Y.)
|December 20, 2014
概括
细胞基因表达的变异性是可以预测的. 转录的分子细节,而不仅仅是调节架构,控制这种变化,使转录噪声成为可调节的特征.
科学领域:
- 分子生物学分子生物学
- 系统生物学 系统生物学
- 遗传学 是一个遗传学.
背景情况:
- 基因表达的细胞间变异性是基因调节研究的一个关键领域.
- 在 prokaryotic 转录调节的理论模型和关于表达变异性的实验发现之间存在差距.
- 现有研究表明,可变性独立于调节架构,与一些分子模型相矛盾.
研究的目的:
- 研究Escherichia coli中转录和基因表达变异性的分子细节之间的关系.
- 为了确定基因表达变异性是否受到促进体强度,转录因子结合和转录因子拷贝数的影响.
- 测试无参数模型是否可以预测观察到的基因表达变异性.
主要方法:
- 以不同强度和转录因子结合特征的大肠杆菌促进体的系统构造.
- 使用信使RNA (mRNA) 光在位杂交来量化基因表达变异性.
- 将实验数据与来自无参数分子模型的预测进行比较.
主要成果:
- 发现基因表达的变异性取决于转录的分子细节.
- 促进体和转录因子参数的系统变化直接影响了mRNA表达的可变性.
- 无参数模型准确预测了实验观察到的基因表达的变异性.
结论:
- 控制转录的分子机制直接决定mRNA表达的变异性.
- 转录噪声是一种可调的参数,这表明它可以通过进化过程来塑造.
- 基因表达的变异性与底层的调节架构并非无关,而是通过转录细节精确控制.
相关概念视频
02:40The Eukaryotic Promoter Region
19.8K
The eukaryotic promoter region is a segment of DNA located upstream of a gene. It contains an RNA polymerase binding site, a transcription start site, and several cis-regulatory sequences. The proximal promoter region is located in the vicinity of the gene and has cis-regulatory sequences and the core promoter. The core promoter is the binding site for RNA polymerase and is usually located between -35 and +35 nucleotides from the transcription start site. The distal promoter regions are...
19.8K
02:40The Eukaryotic Promoter Region
4.4K
4.4K
01:58Cell Specific Gene Expression
17.5K
Multicellular organisms contain a variety of structurally and functionally distinct cell types, but the DNA in all the cells originated from the same parent cells. The differences in the cells can be attributed to the differential gene expression. Liver cells, whose functions include detoxification of blood, production of bile to metabolize fats, and synthesis of proteins essential for metabolism, must express a specific set of genes to perform their functions. Gene expression also varies with...
17.5K
01:58Cell Specific Gene Expression
5.9K
5.9K
02:33Combinatorial Gene Control
10.5K
Combinatorial gene control is the synergistic action of several transcriptional factors to regulate the expression of a single gene. The absence of one or more of these factors may lead to a significant difference in the level of gene expression or repression.
The expression of more than 30,000 genes is controlled by approximately 2000-3000 transcription factors. This is possible because a single transcription factor can recognize more than one regulatory sequence. The specificity in gene...
The expression of more than 30,000 genes is controlled by approximately 2000-3000 transcription factors. This is possible because a single transcription factor can recognize more than one regulatory sequence. The specificity in gene...
10.5K
02:24Regulation 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