マイクロプロセッサ,Setx,Xrn2,およびRrp6は,RNAPIIによる転写の早期終止を誘導するために協力します
Alexandre Wagschal1, Emilie Rousset, Poornima Basavarajaiah
1Laboratoires de Virologie Moléculaire, Institut de Génétique Humaine, CNRS UPR1142, 34396 Montpellier, France.
Cell
|September 18, 2012
まとめ
マイクロプロセッサ複合体は,RNA干渉独立のメカニズムを通じて遺伝子発現を制御します. 終結因子を誘導し,RNAポリメラーゼIIの一時停止と早めの転写終止を誘導し,細胞遺伝子を調節します.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝子規制 遺伝子規制
- エピジェネティクス エピジェネティクス
背景:
- トランスクリプションの延長は,遺伝子調節における重要なステップです.
- RNA干渉 (RNAi) 以外の遺伝子発現におけるマイクロプロセッサ複合体の役割は完全に理解されていません.
研究 の 目的:
- 遺伝子発現におけるマイクロプロセッサ複合体のRNAi独立機能を調査する.
- マイクロプロセッサがトランスクリプションの延長を制御するメカニズムを解明する.
主な方法:
- クロマチン免疫プレシピテーションとハイスループットシーケンシング (ChIP-seq) を組み合わせて,標的遺伝子を特定します.
- RNAの分裂とリボヌクレアゼによる処理の分析.
主要な成果:
- マイクロプロセッサは,RNAポリメラーゼII (RNAPII) の一時停止と早期終了を誘導するために,終止因子 (Setx,Xrn2) とRrp6を募集します.
- マイクロプロセッサによるTAR RNAのクラビングは,Rrp6処理を含む経路を開始し,小さなRNAを生成します.
- この小さなRNAは,HIV-1プロモーターでの転写抑制とクロマチンの改造を媒介する.
- ChIP-seqは,マイクロプロセッサによって調節される細胞遺伝子を特定しました.
結論:
- マイクロプロセッサ複合体は,RNAi独立のメカニズムを通じて遺伝子発現を調節する.
- Drosha/Dgcr8,Xrn2,およびRrp6リボヌクレアゼの共同作用は,RNAPIIの停止と早期終了を媒介する.
- この経路は,RNAPII依存の転写延長のための新しい規制メカニズムを表しています.
関連する概念動画
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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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Eukaryotic RNA Polymerases
RNA Polymerase (RNAP) is conserved in all animals, with bacterial, archaeal, and eukaryotic RNAPs sharing significant sequence, structural, and functional similarities. Among the three eukaryotic RNAPs, RNA Polymerase II is most similar to bacterial RNAP in terms of both structural organization and folding topologies of the enzyme subunits. However, these similarities are not reflected in their mechanism of action.
All three eukaryotic RNAPs require specific transcription factors, of which the...
All three eukaryotic RNAPs require specific transcription factors, of which the...
Chromatin Structure Regulates pre-mRNA Processing
In eukaryotic cells, nascent mRNA transcripts need to undergo many post-transcriptional modifications to reach the cell cytoplasm and translate into functional proteins. For a long time, transcription and pre-mRNA processing were considered two independent events that occur sequentially in the cell. However, it has now been well established that transcription and pre-mRNA processing are two simultaneous processes that are precisely regulated inside the cell.
The chromatin structure, especially...
The chromatin structure, especially...
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Transcriptional attenuation occurs when RNA transcription is prematurely terminated due to the formation of a terminator mRNA hairpin structure. Bacteria use these hairpins to regulate the transcription process and control the synthesis of several amino acids including histidine, lysine, threonine, and phenylalanine. Transcription attenuation takes place in the non-coding regions of mRNA.
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
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