核結合タンパク質とコンデンシンタンパク質によるE. coli染色体の多層構造化

Virginia S Lioy¹, Axel Cournac², Martial Marbouty²

¹Institut de Biologie Intégrative de la Cellule, CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette Cedex, France.

Cell

|January 24, 2018

まとめ

細菌のゲノムは異なる構造領域に編成されています複製終端 (ter) 領域は別個の領域を形成し,他の染色体と比較して異なるタンパク質がDNAの接触を制御する.

科学分野:

微生物学
ゲノミクス
分子生物学

背景:

細菌のゲノムはユカリオットのゲノムと同様にランダムでない折り畳みを表しています
バクテリアの染色体は円形で,複製の起源は1つで,終端 (ter) 領域に向かって双方向のフォークにつながります.

研究の目的:

エシェリキア・コライのゲノムの高次元の構造を調べるため
細菌の染色体を別々の領域に編成する際の特定のタンパク質の役割を解明する.

主な方法:

エシェリキア・コライの高階ゲノム構造を調査した.
コンデンシン MukBEF,ヌクレオイド関連タンパク質 (NAPs) HU,MatP,H-NSの役割を分析した.

主要な成果:

E. coli のゲノムは2つの異なる構造体に分かれています. ter 領域と残りの染色体です.
ter領域の外では,MukBEFとHUタンパク質が大規模なDNA接触 (メガベース範囲) を媒介する.
ter領域内では,MatPはMukBEFを抑制し,より小さな領域 (∼280 kb) に接触を制限し,H-NSは短距離の相互作用を制限する.

結論:

MatPやMukBEFのような特定のタンパク質は細菌の染色体内で独特の構造領域を作り出します
核結合タンパク質は,細菌の染色体組織において,進化的に保存された重要な役割を果たします.

キーワード:

ハンガリー語 Hi-C についてマットP SMC についてバクテリアクロマチンゲノム組織

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