酵母染色体のセントロメア内のメオティック再結合

L S Symington¹, T D Petes

¹Department of Molecular Genetics and Cell Biology, University of Chicago, Illinois 60637.

Cell

|January 29, 1988

まとめ

再結合の一種である遺伝子変換は,他のゲノム領域と同様の周波数で酵母センターメア内で発生します. この研究では,酵母染色体IIIのセントロメアにおける非互換性再結合イベントを調査した.

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
イースト生物学イースト生物学

背景:

セントロメアは,細胞分裂中の染色体分離に不可欠です.
遺伝子変換は,遺伝情報を変化させることができる非相互的な再結合プロセスです.
セントロメア内の再結合を理解することは,ゲノム安定性の理解の鍵です.

研究の目的:

イースト染色体IIIのセントロメア内の遺伝子変換の頻度を測定する.
遺伝子変換イベントがセンターメリック領域にまたがるかどうかを調査する.

主な方法:

ヘテロジゴトの制限部位とセントロメア周りの側面マーカーを持つ酵母菌株の構築.
URA3遺伝子をマーカーとして使用したメオティック再結合イベントの分析.
テトラド分析は,遺伝子変換および共同変換イベントを特定するために行われます.

主要な成果:

URA3遺伝子のメオティック変換は,未選択のテトラド群で約2%の通常の頻度で発生しました.
URA3遺伝子変換イベントの3分の1以上は,セントロメア内のマーカーの共同変換にもつながりました.
いくつかの変換イベントはセントロメアを通して広がり,反対側のマーカーに影響を与えることが観察されました.

結論:

メイオティック遺伝子変換は,他のゲノム配列と比較できる速さで,酵母センターメア内で発生します.
リコンビネーションイベントは,実際にセンターメリック領域を横断し,リンクされた遺伝的マーカーに影響を与えることができます.
この発見は,セントロメアが微生物分裂中の遺伝子変換に対する絶対的な障壁ではないことを示唆している.

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