TERTとRMRPRNAによって形成されるRNA依存型RNAポリメラーゼ
Yoshiko Maida1, Mami Yasukawa, Miho Furuuchi
1Cancer Stem Cell Project, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan.
Nature
|August 25, 2009
まとめ
ヒューマンテロメラーゼ (TERT) は,ミトコンドリアRNA処理 (RMRP) と相互作用して,新しいRNA依存型RNAポリメラーゼを形成する. この複合体は,小さな干渉RNAに処理された二重鎖RNAを生成し,テロメアの維持を超えてTERTの新しい役割を明らかにします.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- 細胞生物学 細胞生物学
背景:
- 構成テロメラーゼ発現は,テロメアの長さを維持することによって,細胞老化を防止します.
- 新興の証拠は,ヒトテロメラーゼ逆転写酵素触媒子ユニット (TERT) がテロメラー延長を超えた機能を持っていることを示しています.
- ミトコンドリアRNA処理エンドロビヌクレアゼ (RMRP) の変異は,軟骨-毛の低増殖を引き起こし,プレオトロプ症候群である.
研究 の 目的:
- 人間のTERT.の非テロメア機能を調査する.
- TERT.の新たな相互作用パートナーと生化学的活動を特定する.
- TERTのエクストラテロメア作用の基礎となる分子メカニズムを解明する.
主な方法:
- コイムノプレシピテーションは,TERTの相互作用するパートナーを特定するための検査である.
- TERT-RMRP複合体の酵素活性を特徴付けるための生化学的分析.
- 小さなRNAの生産を評価するためのRNA干渉とDicerノックダウン実験.
主要な成果:
- 人間のTERTは,RMRPのRNA成分と直接相互作用する.
- TERTとRMRPは,RNA依存型RNAポリメラーゼ (RdRP) 活性を持つ異なるリボ核タンパク質複合体を形成する.
- この複合体は二重鎖RNAを生成し,Dicerによって小さな干渉RNAに処理されます.
結論:
- TERTとRMRPからなる,哺乳類RNA依存型RNAポリメラーゼの新型が特定されました.
- TERTは,テロメア維持とは関係なく,これまで認識されていない酵素的機能を有している.
- この発見は,細胞生理学と疾患におけるTERTの役割を理解するための新しい道を開きます.
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