Physarum polycephalumの核rDNAに移動性グループIイントロンが含まれている
1Section of Biochemistry, Molecular and Cell Biology, Cornell University, Ithaca, New York 14853.
Cell
|February 10, 1989
まとめ
Physarum polycephalumの移動核イントロンが特定されました. このグループIイントロン (イントロン3) は,遺伝子変換によってDNAに変換され,核イントロン移動性とエンドヌクレアース活性を示します.
科学分野:
- 分子生物学 分子生物学
- 遺伝学 遺伝学とは
- バイオケミストリー バイオケミストリー
背景:
- 核イントロンは,典型的には非移動性遺伝的要素である.
- グループIのイントロンの移動性は,主に有機体で観察されています.
研究 の 目的:
- Physarum polycephalum.の特定の核群Iイントロン (イントロン3) の移動性を調査する.
- イントロンの転置のメカニズムを決定し,暗号化された酵素活性を識別する.
主な方法:
- イントロン欠乏菌株とイントロン含有菌株からのアメーバの交尾.
- イントロンの統合を観察するために,交配後のDNA配列の分析.
- クローンイントロンのインビトロ転写とトランスレーションで,核酵素の活性を評価する.
主要な成果:
- Intron 3は,アミーバの交配後の受容体rDNA分子へのサイト固有の転移を実証した.
- 隣接する配列の共同変換や受容者のDNAにおける二重鎖の断裂を含む遺伝子変換の証拠.
- インビトロ研究では,イントロ3が酵素活性でサイト特異な核酵素をコードしていることが確認されました.
結論:
- 核群Iのイントロンは,移動可能な遺伝的要素である.
- イントロン3の転移は,自己暗号化されたエンドヌクレアゼによって誘発される遺伝子変換によって起こります.
- この研究は,核イントロンの転置に関する最初の実験的証拠と,RNAポリメラーゼIトランスクリプトによって暗号化されたタンパク質の希少な例を提供します.
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