E. coli の細胞分裂サイクル中に,積極的に分割する F プラズミドのサブセルラー分布

H Niki¹, S Hiraga

¹Department of Molecular Cell Biology, Institute of Medical Embryology and Genetics, Kumamoto University School of Medicine, Kumamoto, Japan. niki@gpo.kumamoto-u.ac.jp

Cell

|September 23, 1997

まとめ

Fプラズミド分割システム (sopABC) は,娘細胞への正確な分離を保証します. このシステムは,細胞分裂中に複製されたプラズミッドを特定の細胞位置に正確に配置し,結合します.

科学分野:

分子生物学は分子生物学である.
微生物学微生物学とは
遺伝学遺伝学とは

背景:

Fプラズミッドは,細菌の細胞分裂中に,娘細胞に正確な分割を必要とします.
sopABC系は,sopa,sopaB,sopaCの要素で構成され,この忠実な分離を媒介することが知られている.
プラズミド分割の亜細胞動態を理解することは,細菌遺伝学にとって極めて重要です.

研究の目的:

細胞分裂中のミニ-F-プラズミド分子の亜細胞分布を視覚化および特徴づけること.
プラズミドの空間的組織と結合におけるsopABCシステムの役割を明らかにする.
sopABCロクスが,細菌のヌクレオイドに相対してプラズミドの局所化をどのように影響するかを決定する.

主な方法:

バクテリア細胞内のミニF-プラズミド分子を視覚化するために,光 in situ ハイブリダイゼーション (FISH) を利用しました.
sopABCセグメントを含むミニ-Fプラズミドの細胞下部位を,それを持たないものと比較した.
細胞分裂段階とヌクレオイドの存在に関連したプラズミド分布の観測.

主要な成果:

sopABCセグメントを持つミニ-Fプラズミッドは,新生児の細胞のミッドセルに局所されました.
複製されたプラズミッドは後に移動し,分裂が完了するまで細胞四分の一の位置 (1/4と3/4) に縛られました.
sopABCセグメントが欠けていたミニ-Fプラズミッドはランダム分布を示し,ヌクレオイドが占有する領域を回避した.

結論:

sopABCシステムは,複製されたFプラズミドの正確な位置付けと安定した結合に不可欠です.
このシステムは,プラズミドを特定の細胞下部部位に積極的に誘導し,娘細胞への分離を保証します.
プラズミド分割は,細胞の伸びとは関係なく,sopABCロカスによって媒介される,活発で指向されたプロセスです.

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