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Dissection of Hippocampal Dentate Gyrus from Adult Mouse
Published on: November 18, 2009
哺乳類のメッセンジャーRNAに埋め込まれた不連続なハンマーヘッドリボ酵素
Monika Martick1, Lucas H Horan, Harry F Noller
1Center for Molecular Biology of RNA, University of California, Santa Cruz, California 95064, USA. mmartick@yahoo.com
Nature
|July 11, 2008
まとめ
遺伝子を調節するリボ酵素は,ネズミのClec2遺伝子3'未翻訳領域で発見されました. これらの不連続なハンマーヘッドリボ酵素は自己分裂し,タンパク質発現を減少させ,新しい転写後の遺伝子調節機構を明らかにします.
科学分野:
- 分子生物学は分子生物学である.
- RNA 生物学 RNA 生物学
- 遺伝子規制 遺伝子規制
背景:
- mRNA未翻訳領域 (UTR) の構造RNAは,遺伝子発現を調節する.
- バクテリアのリボ酵素は,5' UTRにおける自己分裂によって遺伝子発現を制御する.
- ユカリオットのmRNAに遺伝子を調節するリボ酵素が存在するかどうかは,未解決の問題である.
研究 の 目的:
- ユカリオットmRNAにおける遺伝子調節リボ酵素の存在と機能を調査する.
- ネズミのC型レクチンII型 (Clec2) 遺伝子の3'UTR内の新しいリボエンザイム構造を特定する.
主な方法:
- ハンマーヘッドRNAモチーフ検索を使用して,保存されていない領域の緩和された境界線を設けました.
- ネズミのClec2遺伝子の3'UTR内に断続的なリボ酵素配列が検出されました.
- 実験室内および体内での自己分裂活性が実証され,マウス細胞におけるタンパク質発現への影響が評価されました.
主要な成果:
- ネズミのClec2遺伝子3' UTRs.で高度に活性なハンマーヘッドリボ酵素を特定しました.
- 活性構造に組み合わされる断続的なリボジーム断片を発見した.
- in vitroおよびin vivoで自己分裂とマウス細胞におけるタンパク質発現の低下が確認されています.
結論:
- 断続的なリボジーム配列を含む転写後の遺伝子調節の新しいメカニズムが特定されました.
- このメカニズムは,骨の改造と免疫応答に関与する哺乳類のCLEC2タンパク質の発現を調節する可能性があります.
- この発見は,真核生物の遺伝子調節におけるリボ酵素のより広範な役割を示唆している.
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