ユカリオット進化: カノニカル・イントロンの初期の起源
Alastair G B Simpson1, Erin K MacQuarrie, Andrew J Roger
1Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada. simpson@hades.biochem.da.ca
Nature
|September 20, 2002
まとめ
kanonical spliceosomal intronsは,以前考えられていたように遅れてではなく,おそらく真核生物の進化の非常に早い段階で発生した. Carpediemonas membraniferaにおける正常なエウカリオットイントロンの発見は,イントロンの進化に関する以前の仮定に異議を唱える.
科学分野:
- 分子生物学は分子生物学である.
- 進化生物学の進化生物学について
- ゲノミクスゲノミクスとは
背景:
- スプライソソームのイントロンは,真核生物ゲノムの重要な特徴です.
- 以前は,イントロンは,真核生物の進化の遅い段階で発生したと考えられていた.
- ジアルディアで単一の異常イントロンの発見は,再評価を促した.
研究 の 目的:
- スプライソソーマイントロンの進化的起源を調査する.
- 初期に分裂したエウカリオートにカノニカル・イントロンが存在するかどうかを判断する.
主な方法:
- Carpediemonas membranifera.のゲノムにおけるイントロンの分析.
- イントロン境界配列と既知のエウカリオトスプレイスサイトの比較.
主要な成果:
- Carpediemonas membraniferaで正常な真核生物の境界配列を持つイントロンを特定した.
- これらの発見は,初期に分裂したエウカリオートにカノニカル・イントロンの存在を示唆している.
結論:
- kanonical spliceosomal intronsは,おそらく,真核生物の進化の非常に早い段階で発生した.
- Carpediemonas membraniferaにおける正常なイントロンの存在は,遅い起源の仮説を否定する.
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