細胞因子は再結合と成長期を組み合わせる:ラムダ部位特異再結合経路における新しい成分の特徴化

J F Thompson, L Moitoso de Vargas, C Koch

Cell

|September 11, 1987

まとめ

逆転刺激因子 (FIS) は,特定の細胞環境におけるラムダファグのDNA切除を強化する. この宿主タンパク質はXisと協力するが,再結合には不可欠ではなく,結合は細胞成長段階によって異なる.

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:

ラムダ部位特異再結合は,細菌のラムダ生物学の重要なプロセスである.
ファグの再結合を調節する宿主因子の役割は完全に理解されていません.

研究の目的:

新しい宿主タンパク質,逆転刺激因子 (FIS) の機能を,ラムダ部位特異的再結合で特徴づける.
FISがラムダ切除と統合に影響を与えるメカニズムを解明する.

主な方法:

FIS結合と再結合の刺激を評価するためのインビトロ生化学測定法.
FIS,Xis,およびlambda attPサイト間のDNA結合相互作用の分析.
FIS結合部位の占有率と細胞成長の関係を調べるインビボ研究.

主要な成果:

FISはlambda attPサイトに結合し,Xisの結合領域を重複させ,Xisと協力的に結合することができます.
FISはLambda excisionをインビトロで20倍まで刺激し,特にXis濃度が最適以下である場合に効果的です.
FISは統合的再結合に影響を与えず,Xisから独立して切除を媒介することはできません.
FISがその部位にインビボで結合することは,細胞成長段階に依存し,指数関数段階では完全に占められ,静止段階では空いている.

結論:

FISは,Xisとの協力によってラムダ切除を調節する規制主体因子です.
FISの活動はXis濃度に依存しており,統合再結合に影響を与えない.
細胞のFISレベルまたはアクセシビリティは,生体内でラムダ再結合経路を動的に調節する.

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