E. coliにおけるmRNAの翻訳独立の局所化

Keren Nevo-Dinur¹, Anat Nussbaum-Shochat, Sigal Ben-Yehuda

¹Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, The Hebrew University Faculty of Medicine, Post Office Box 12272, Jerusalem 91120, Israel.

Science (New York, N.Y.)

|February 26, 2011

まとめ

バクテリアのメッセンジャーRNA (mRNA) は,タンパク質生成前に特定の細胞部位に移動することができます. 膜タンパク質遺伝子のシス作用配列は,バクテリアの内膜にmRNAを誘導する.

科学分野:

バクテリアの細胞生物学
遺伝子発現の分子メカニズム
タンパク質の局所化

背景:

細菌細胞の組織は,精密なタンパク質の局所化に依存しています.
タンパク質の局所化メカニズムは,タンパク質特性にのみ依存すると考えられていた.
転写と翻訳は,一般的にバクテリアで結合されていると考えられています.

研究の目的:

伝達 RNA (mRNA) がバクテリアの特定の細胞下部部位をターゲットにできるかどうかを調査する.
mRNAのターゲティングが翻訳依存型か独立型かを判断する.
mRNAの局所化に起因する配列を特定する.

主な方法:

Escherichia coli.でmRNAの局所化を研究した.
研究された翻訳独立のmRNAターゲティング.
遺伝子のトランスメブランコード領域内のシス作用配列を特定した.

主要な成果:

特定のバクテリアのmRNAは,翻訳とは無関係に特定の細胞目的地 (細胞質,極,内膜) を標的とする.
超膜コード配列内のCis作用配列は,mRNAを内膜にターゲティングするには必要で十分である.
合成後の特定の細胞領域へのmRNA移行が実証されています.

結論:

バクテリアのmRNAの局所化は,タンパク質特性にのみ依存するものではありません.
mRNA分子は,それらの暗号化されたタンパク質が必要とされる細胞部位に積極的に移住することができます.
これは,バクテリアの転写後の調節の新しい層を明らかにしています.

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