Rpn1は,プロテアソームによる基板結合とデウビキチン化のための隣接する受容体部位を提供します
Yuan Shi1, Xiang Chen2, Suzanne Elsasser1
1Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
Science (New York, N.Y.)
|February 26, 2016
まとめ
研究者らは酵母に6番目のプロテアソマルユビキチン受容体Rpn1を特定した. Rpn1には,タンパク質分解経路に不可欠な,ユビキチンとユビキチンのようなドメインを認識する2つの結合部位があります.
科学分野:
- 細胞生物学
- 生物化学
- 分子生物学
背景:
- タンパク質の分解は 細胞の機能に不可欠です
- プロテアソームは タンパク質の分解を 司る重要な細胞機構です
- ウビキチンの認識は,タンパク質をタンパク質分解のターゲットにするために重要なステップです.
研究 の 目的:
- プロテアソムの新しいユビキチン受容体を特定する.
- プロテアソームによるユビキチン認識のメカニズムを解明する.
- 基板の選択と処理における Rpn1 の役割を理解する.
主な方法:
- 酵母遺伝学と生化学
- プロテアソームの浄化と分析
- Rpn1-ubiquitin複合体のX線結晶学
主要な成果:
- 既知の5つのプロテアソマルユビキチン受容体は,酵母におけるユビキチン認識に不可欠ではない.
- 第6の受容体であるRpn1が特定され,特徴づけられました.
- Rpn1は,ユビキチンとユビキチン類似ドメイン (UBL) に対して2つの異なる結合部位 (T1とT2) を有する.
- T1部位は好ましくライシン48結合ユビキチン鎖に結合し,基質の認識を媒介する.
- T2サイトは,デウビキチン化酵素 Ubp6 の UBL ドメインと結合し,ウビキチン鎖の分解を容易にする.
結論:
- Rpn1は酵母における新規かつ必須のタンパク質性ユビキチン受容体である.
- Rpn1のダブルサイト認識メカニズムは,効率的なタンパク質分解に不可欠です.
- Rpn1は基板認識,シャットリング因子相互作用,およびタンパク質処理のためのデウビキチネーションを統合する.
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