挿入要素IS102によって生成された新しいタイプのトランポゾンで,pSC101の派生体であるpSC101に存在する
Cell
|August 1, 1982
まとめ
研究者らは,プラズミドの共同統合を促進する新型トランポゾンであるTn1021とTn1022を発見した. これらの要素は,IS102挿入配列から発生し,細菌遺伝学のトランポゾン多様性と機能に関する新しい視点を提供します.
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
- 微生物学 微生物学とは
背景:
- pSC101の誘導体であるテトラサイクリン耐性プラズミッドpYM103は,挿入要素IS102.2の単一のコピーを含んでいる.
- トランポゾンは,ゲノム内の位置を変えることができる移動性遺伝的要素です.
研究 の 目的:
- プラズミドpYM103とプラズミドCol E1.1.の共同統合を媒介する新型トランポゾンを特徴付ける.
- これらの新しいトランポゾン形成における挿入要素IS102の役割を明らかにする.
主な方法:
- プラズミドの共統合に関与するDNAセグメント (Tn1021とTn1022) の識別と特徴付け.
- 新型トランポゾン構造の分析,その端末と内部DNA組成を含む.
- 新しいトランポゾンと既知のトランポゾンファミリーの比較.
主要な成果:
- 2つの新しいトランポゾン,Tn1021 (6kb) とTn1022 (10kb) が特定され,pYM103とCol E1.1の共統合を介した.
- コインテグレーツは9bpの標的配列の直接複製を交差点で示した.
- 2つのトランポゾンには,片端にIS102と,テトラサイクリン耐性遺伝子を含むpYM103DNAの長さが変化するDNAが含まれています.
- ターミナル・インバーテッド・リピート (ターミナル・インバーテッド・リピート) は,両方の新型トランポゾンで観察されました.
- IS102は,Tn1021とTn1022を生成する要素として関与していた.
結論:
- 発見は,一般的なIS関連トランスポーソンと異なる新種のトランスポーソンのクラスを明らかにしています.
- IS102は,Tn1021とTn1022の形成と機能を推進する重要な要素です.
- これらのトランポゾンは,Tn3ファミリーとファグMuとの類似性を共有し,移動性遺伝子要素の既知の多様性を拡大する可能性があります.
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