人类介质子单元MED26作为转录延长因子的对接点
Hidehisa Takahashi1, Tari J Parmely, Shigeo Sato
1Stowers Institute for Medical Research, Kansas City, MO 64110, USA.
Cell
|July 7, 2011
概括
人类中介子单元MED26充当分子开关,协调转录启动和延长. 它通过与关键蛋白质复合体相互作用,促进RNA聚合酶II (Pol II) 从促进子近位暂停过渡到生产延长.
科学领域:
- 分子生物学分子生物学
- 基因规则 基因规则
- 转录机制 转录机制
背景情况:
- 促进 RNA 聚合酶 II (Pol II) 的近端暂停是基因转录激活中的关键调节步骤.
- 暂停的Pol II释放到生产性延伸中涉及超延伸复合体 (SEC) 的招募,但招募机制仍然不清楚.
研究的目的:
- 调查人类调解员MED26小组在招聘SEC和规范Pol II暂停中的作用.
- 阐明 MED26 促进从转录启动到延长过渡的机制.
主要方法:
- 在MED26.2的保留N终端域内识别对接点.
- 分析MED26与SEC,ELL/EAF含有复合物的相互作用,以及一般启动因子TFIID.
主要成果:
- MED26拥有SEC和另一个包含ELL/EAF的综合体的重叠对接站点,以及TFIID.
- 有证据表明,MED26可以作为一个分子开关,与TFIID,然后ELL/EAF/P-TEFb复合体连续相互作用.
结论:
- 在促进Pol II从启动到生产延长的过渡中,MED26发挥着至关重要的作用.
- 作为一个支架,MED26协调了启动因子与延长因子的交换,以促进转录.
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...
RNA Polymerase II Accessory Proteins
Proteins that regulate transcription can do so either via direct contact with RNA Polymerase or through indirect interactions facilitated by adaptors, mediators, histone-modifying proteins, and nucleosome remodelers. Direct interactions to activate transcription is seen in bacteria as well as in some eukaryotic genes. In these cases, upstream activation sequences are adjacent to the promoters, and the activator proteins interact directly with the transcriptional machinery. For example, in...
RNA Polymerase II Accessory Proteins
Proteins that regulate transcription can do so either via direct contact with RNA Polymerase or through indirect interactions facilitated by adaptors, mediators, histone-modifying proteins, and nucleosome remodelers. Direct interactions to activate transcription is seen in bacteria as well as in some eukaryotic genes. In these cases, upstream activation sequences are adjacent to the promoters, and the activator proteins interact directly with the transcriptional machinery. For example, in...
Master Transcription Regulators
Master transcription regulators are regulatory proteins that are predominantly responsible for regulating the expression of multiple genes. Often these genes work in concert to drive a complex process. Activation of a master transcription regulator can lead to a cascade of transcriptional activation necessary for that outcome. These regulators can directly bind to the regulatory sequences of the various genes involved, or they can indirectly regulate transcription by binding to regulatory...
Master Transcription Regulators
Master transcription regulators are regulatory proteins that are predominantly responsible for regulating the expression of multiple genes. Often these genes work in concert to drive a complex process. Activation of a master transcription regulator can lead to a cascade of transcriptional activation necessary for that outcome. These regulators can directly bind to the regulatory sequences of the various genes involved, or they can indirectly regulate transcription by binding to regulatory...


