酵素上の再折り畳みにより,CCA添加酵素による小さなRNAとtRNAの監視が可能になります

Claus-D Kuhn¹, Jeremy E Wilusz², Yuxuan Zheng³

¹W.M. Keck Structural Biology Laboratory, Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA.

Cell

|February 3, 2015

まとめ

CCA添加酵素は,その機械的作用に対する反応を感知することで,安定したRNAと不安定なRNAを区別する. 安定したRNAは排出され,不安定なRNAは第二の触媒サイクルを経て分解する.

科学分野:

分子生物学は分子生物学である.
RNA 生物学 RNA 生物学
バイオケミストリーバイオケミストリー

背景:

ユカリオットのトランスクリプションは,MALAT1とMenβを含む長いノンコーディングRNA (lncRNA) を生成します.
いくつかのlncRNAは,成熟したトランスクリプトとともに,tRNAのような小さなRNAを生成する.
CCA添加酵素は,tRNAおよびtRNAのようなRNAの安定性を調節する.

研究の目的:

CCA添加酵素が安定したRNAと不安定なRNAを区別するメカニズムを解明する.
tRNAのようなRNAと本来のtRNAの処理方法を理解する.

主な方法:

異なるRNA基板におけるCCA添加酵素活性に関する特徴.
RNAリフォールドと触媒サイクルの分析.
酵素-RNA相互作用と力学的力の調査.

主要な成果:

CCA添加酵素は,不安定なRNAに第2のCCAリピートを加え,分解を開始します.
安定したRNAとtRNAのようなトランスクリプトは,最初のCCA添加後に放出されます.
酵素誘発の核酸結合は,スクルーの動きを誘発し,RNAの運命を区別するトルクを生み出します.

結論:

RNAは,CCA添加酵素の機械的尋問に対する差異的反応を通じて,自律的に安定性を読み取ります.
CCA添加酵素は分子のように作用し,構造的反応に基づいてRNA基板を区別する.

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