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ヘリコースDed1pは,5' UTRにおける近縁の翻訳開始コドンの使用を制御する
Ulf-Peter Guenther1, David E Weinberg2,3,4, Meghan M Zubradt2,5
1Center for RNA Science and Therapeutics, School of Medicine, Case Western Reserve University, Cleveland, OH, USA.
Nature
|June 29, 2018
まとめ
DEAD-box RNAヘリケーズDed1p (およびその哺乳類のオートログDDX3) は,特にmRNA構造に対する反応として,近同類のスタートコドン使用を制御することによって,翻訳開始を調節する. このメカニズムは タンパク質の合成と 細胞のメオシスのようなプロセスに 極めて重要です
科学分野:
- 分子生物学
- 遺伝学
- 生物化学
背景:
- DEAD-box RNAヘリケーズDed1p (酵母) とDDX3 (哺乳類) は,トランスレーション開始に不可欠である.
- DDX3の調節不良は癌や知的障害に関与しており,DDX3はウイルス感染症の標的である.
- Ded1p/ DDX3が翻訳開始時にRNAと相互作用する正確なメカニズムは不明である.
研究 の 目的:
- 翻訳開始時のRNAの関与におけるDed1pの役割を解明する.
- Ded1pの活性,mRNAの構造,および代替翻訳開始コドンの使用との関連を調査する.
- 微分化などのプロセスにおけるこの調節プログラムの生理学的関連性を理解する.
主な方法:
- 翻訳,RNA構造,およびDed1p-RNA結合の統合されたトランスクリプトーム全体の分析.
- 5' 未翻訳領域 (UTR) のRNA構造と翻訳開始に対するDed1p活性抑制の影響を評価した.
- 分離過程中のDed1pレベルと代替翻訳開始を調べた.
主要な成果:
- Ded1pは,mRNAのエントリーチャネルでの翻訳前イニシアチブ複合体と関連しています.
- Ded1pの活性抑制は5' UTRのRNA構造の増加につながり,上流の近縁のスタートコドンから翻訳開始を促進します.
- Ded1p抑制は,メインの開いた読み取りフレームからのタンパク質合成を低下させ,メオシス中の代替翻訳開始部位を活性化します.
結論:
- Ded1pは,5' UTRのmRNA構造の近くに位置する近縁のスタートコドンの選択を制御することによって,翻訳開始を調節する.
- Ded1p,近親性のスタートコドン活性化,およびmRNA構造をリンクする規制プログラムがタンパク質合成を制御する.
- このDed1p媒介の調節は,メオシスを含む細胞過程において重要な役割を果たします.
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