熱ショック反応のトランスレーション制御を指示するダイナミック m(6) A mRNAメチル化
Jun Zhou1, Ji Wan1, Xiangwei Gao1
1Division of Nutritional Sciences, Cornell University, Ithaca, New York 14853, USA.
Nature
|October 13, 2015
まとめ
熱ショックストレスは,mRNA 5'未翻訳領域 (5'UTRs) のN(6) -メチラデノシン (m(6) A) 変異を誘発する. このダイナミックなメチル化により,キャップ独立変換が促進され,ストレス反応が強化されます.
科学分野:
- 分子生物学
- RNA 生物学
- 遺伝子発現の規制
背景:
- N(6) -メチラデノシン (m(6) Aは,多様な役割を持つ一般的なmRNA変異である.
- m(6) Aは哺乳類のmRNAに非対称的に分布し,5' 未翻訳領域 (5' UTR) でメチル化が少ない.
- 5'UTR m(6) Aの調節と機能は,特に翻訳開始では,まだ十分に理解されていません.
研究 の 目的:
- ストレス条件下での5'UTR m(6) Aの調節と機能を調査する.
- 熱ショック時のmRNA翻訳開始におけるm(6) Aの役割を決定する.
- ストレス下での選択的mRNA翻訳のメカニズムを解明する.
主な方法:
- 熱ショックに対する mRNA メチル化パターンの分析
- A結合タンパク質 (YTHDF2) とデメチラゼ (FTO) の局所化と機能を調査する.
- レポーターアッセイと特定のmRNA (Hsp70) を用いて翻訳開始に対する5'UTR m(6) Aの影響を評価する.
主要な成果:
- 熱ショックストレスは,新たに転写されたmRNAの5'UTRで好ましいメチル化を誘導する.
- YTHDF2のストレス誘発核局所化は,FTO脱メチル化を阻害することによって5'UTRメチル化を保存する.
- 増加した5'UTR m(6) Aは,Hsp70 mRNAで示されたキャップ独立の翻訳開始を促進する.
結論:
- 5'UTR m(6) Aのダイナミック調節は,細胞のストレス反応に不可欠です.
- m(6) 5'UTRのAは,熱ショック下でのキャップ独立変換開始メカニズムを提供します.
- この研究は,m ((6) Aによって媒介される熱ショック反応における新しいトランスレーション制御経路を明らかにした.
関連する概念動画
Regulation of Expression at Multiple Steps
1.5K
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...
1.5K
Translational Regulation
819
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,...
819
RNA Stability
36.3K
Intact DNA strands can be found in fossils, while scientists sometimes struggle to keep RNA intact under laboratory conditions. The structural variations between RNA and DNA underlie the differences in their stability and longevity. Because DNA is double-stranded, it is inherently more stable. The single-stranded structure of RNA is less stable but also more flexible and can form weak internal bonds. Additionally, most RNAs in the cell are relatively short, while DNA can be up to 250 million...
36.3K
RNA Stability
12.2K
12.2K
Regulation of Expression Occurs at Multiple Steps
27.1K
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...
27.1K
Master Transcription Regulators
8.0K
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...
8.0K


