トリパノソームミトコンドリア 3'端のウリジリルトランスファーゼ (TUTase):U挿入/消去RNA編集の鍵となる酵素
Ruslan Aphasizhev1, Sandro Sbicego, Marian Peris
1Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Cell
|March 15, 2002
まとめ
研究者は,リーシュマニアのミトコンドリアから3'-端末RNAウリジルトランスフェラーゼ (TUTase) を浄化し,その遺伝子をクローンした. この酵素は,Trypanosoma bruceiのRNA編集に不可欠であり,その発現が抑制されると寄生虫の生存能力に影響を与えます.
科学分野:
- 分子生物学は分子生物学である.
- 寄生虫学とは,寄生虫学である.
- バイオケミストリー バイオケミストリー
背景:
- RNA編集は,キネトプラスティドにおける重要な転写後のプロセスである.
- 3'端末RNAウリジルトランスフェラーゼ (TUTases) は,RNAを誘導するためにウリジンを加えることでRNA編集に重要な役割を果たします.
- TUTaseの機能を理解することは,これらの生物のRNA代謝を理解するために不可欠です.
研究 の 目的:
- Leishmania tarentolae.からの3'末端RNAウリジリルトランスフェラーゼ (TUTase) を浄化し,特徴づけること.
- Leishmania tarentolaeとTrypanosoma bruceiの両方のTUTASE遺伝子をクローンし,発現させるためでした.
- トリパノソーマブルセイにおけるTUTaseのインビボ機能と相互作用を調査する.
主な方法:
- Leishmania tarentolae mitochondriaから酵素を浄化する.
- プロカリオット系における遺伝子クローニングと発現.
- トライパノソーマブルセイにおけるRNA干渉 (RNAi) を用いたインビボ研究.
- コプレシピテーションアッセイでは,抗-TUTase抗血清を使用しています.
主要な成果:
- A Mg(2+) に依存する3'U添加の特異性TUTASEを浄化し,特徴づけました.
- この酵素は,約500 kDaのオリゴーマーと約700 kDaの複合体として体内に存在します.
- TUTaseはRNAリガゼと相互作用し,RNAを誘導することが判明しました.
- RNAiによるTUTase発現の抑制は,RNA編集のダウンレギュレーションにつながり,寄生虫の生存能力に影響を与えました.
結論:
- 浄化されたTUTASEは酵素活性であり,3'-U加減に特異的です.
- TUTaseは複数の複雑な形態でin vivoで機能し,他の主要なRNA処理因子と相互作用する.
- TUTaseはRNA編集とTrypanosoma bruceiの寄生虫生存に不可欠であり,治療標的としての可能性を強調しています.
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