RNAポリメラーゼIIの大型サブユニットにおける機能的冗長性と構造的ポリモルフィズム

M Nonet, D Sweetser, R A Young

Cell

|September 11, 1987

まとめ

RNAポリメラーゼIIの大型サブユニット

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
バイオケミストリーバイオケミストリー

背景:

RNAポリメラーゼII (Pol II) は,遺伝子転写に不可欠である.
Pol II大サブユニットのC端領域 (CTD) は,繰り返しヘプタペプチド配列を特徴としています.
これらの繰り返しの正確な機能と本質は完全に理解されていません.

研究の目的:

RNAポリメラーゼII大サブユニットにおけるヘプタペプチド重複配列の細胞活性の必要性を調査する.
RNAポリメラーゼIIの機能に必要な最小の繰り返し数を決定する.
転写における繰り返し数変化の影響を調査する.

主な方法:

酵母RNAポリメラーゼII大亜単体のカーボキシ末端コード配列における片方向のデレーションの構築と分析.
RNAポリメラーゼII大サブユニットにおける完全なヘプタペプチドの繰り返し数に基づく細胞活性の評価.

主要な成果:

RNAポリメラーゼIIの生存能力には,少なくとも10つのヘプタペプチドの繰り返しが必要である.
10〜12回の繰り返しは,条件付きの生存能力を授け,13回以上の繰り返しは,無条件の生存能力を保証する.
不活性な変異体における断片化されたRNAポリメラーゼIIサブユニットは安定しているが,機能的には欠陥がある.
繰り返し単位の数は,野生型酵母菌株では多形である.

結論:

RNAポリメラーゼIIのヘプタペプチドリピートドメインは,細胞生存に不可欠である.
繰り返しの数はRNAポリメラーゼII機能と生物の生存能力と直接相関しています.
繰り返し数の変動は,異なる酵母菌株の転写調節に影響を与える可能性があります.

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