プラズミドDNAからバイパレンタルフィギュア8分子が酵素によって形成され,E. coliで分解される
Cell
|March 1, 1983
まとめ
図8 遺伝的再結合における重要な中間物質であるDNA分子は,細菌酵素によって成熟したDNA製品に分解することができる. このプロセスは,親のDNAと再結合DNAの両方を生成し,recA遺伝子を必要とせずに,中間再結合を模倣します.
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
- DNAの複製と修復を図っています.
背景:
- 一般的な遺伝的再結合は,二重鎖のDNA分子が単一鎖のクロスオーバーで結びついているホリデイ・ジャンクションを含む.
- 円形のDNA分子はクロスオーバーポイントでフィギュア8の構造を形成し,再結合における重要な中間物質として機能します.
- recA遺伝子産物は,E. coliにおける同質再結合に典型的に不可欠である.
研究 の 目的:
- 再結合中介物質としてのフィギュア8のDNA構造の役割を調査する.
- これらの構造が成熟した再結合DNA製品に分解できるかどうかを in vitro および in vivo で判定する.
- figure-eight構造の解明のためにrecA遺伝子製品の必要性を評価する.
主な方法:
- 浄化されたE. coli酵素を用いて,双親のフィギュア8型DNA分子を部分的に同質のプラズミドから in vitro で構築した.
- 構築されたフィギュア8のDNA分子は,recA-E. coli細胞に転移されました.
- 解決製品は,親型および再結合型,クロスオーバー頻度,および不一致修復について分析されました.
主要な成果:
- figure-eight構造が recA-E. coli に変異すると,その分解により,モノメリックまたは二重性プラズミドの子孫となる.
- 図8の分子の成熟により,親型のDNAと再結合型DNAの両方が,クロスオーバー頻度が最大50%に達した.
- 分解された分子内のハイブリッドDNAの領域は,不一致修復の能力を実証しました.
結論:
- 双親型のフィギュア8型DNA分子は,効果的な再結合中間体として機能する.
- これらの中間物質は,recA遺伝子産物とは無関係に細菌酵素によって成熟した再結合DNA製品に分解することができる.
- 解消剤は,ミオシス中に形成された再結合染色体と類似した特性を持ち,ミスマッチの修復も含む.
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