G四重複のRNAは,ヒトのVEGF IRESにおけるキャップ独立の翻訳開始に不可欠である
Mark J Morris1, Yoichi Negishi, Cathy Pazsint
1Department of Chemistry and Biochemistry, Kent State University, Kent, Ohio 44242, United States.
Journal of the American Chemical Society
|November 26, 2010
まとめ
この研究では,VEGF mRNAにおける切り替え可能なRNA G-クアドルプレックスが明らかになりました.
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
- 構造 RNA 構造
背景:
- 5'-UTRのRNAG四重複体は,通常,キャップ依存翻訳を抑制する.
- 内部リボソームエントリーサイト (IRES) 媒介翻訳におけるG四重複体の役割は,あまり理解されていない.
研究 の 目的:
- 人間のVEGF mRNAの5'-UTRに含まれるG元素の役割を調査する.
- この要素がG四重複構造を形成しているかどうかを判断し,翻訳開始におけるその機能.
主な方法:
- 構造分析により,G-四重複の形成を特定する.
- 翻訳開始を評価するための機能的分析.
- 配列-構造-機能関係を探求するための変異性研究.
主要な成果:
- VEGF mRNA 5'-UTR.内の"切り替え可能な"RNA G-四重複構造が実証されました.
- このG-クアドルプレックスをIRESによる翻訳開始に不可欠なものとして紹介しました.
- 変換規則に影響を与える配列依存型コンフォメーションスイッチングを特定した.
結論:
- これは,IRES媒介による翻訳に不可欠な形状的に柔軟なRNA G-四重複体の最初の報告です.
- VEGF mRNA G-quadruplexは,トランスレーション開始において調整可能な規制的役割を果たしている.
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