パターン誘発免疫におけるキャップ・インデペンデント・トランスレーションのイニシアチブ・モジュールとしてのPABP/プーリン豊富なモチーフ
Jinlong Wang1, Xing Zhang1, George H Greene1
1Howard Hughes Medical Institute, Duke University, Durham, NC 27708, USA; Department of Biology, Duke University, Durham, NC 27708, USA.
Cell
|July 30, 2022
まとめ
植物では,GCN2/eIF2α経路とは独立して,ストレス中に防御mRNAの選択的な翻訳のために,ユニークなR-モチーフの内部リボソームエントリーサイト (IRES) を利用する. このプロセスは,ポリA結合タンパク質とMPK3 / 6のリン酸化を含み,免疫信号をタンパク質合成にリンクします.
科学分野:
- 植物分子生物学
- ストレス反応メカニズム
- 遺伝子発現の調節
背景:
- ユカリオットは通常,GCN2/eIF2αシグナル伝達を介してストレス下での翻訳を再プログラムします.
- しかし植物はこの経路から独立して ストレス反応を示します
- 植物におけるパターン誘発免疫 (PTI) は,一般的な翻訳を阻害するためにmRNAの断片化を伴う.
研究 の 目的:
- 植物 PTI 中の選択的防御 mRNA 翻訳のメカニズムを解明する.
- R-モチーフ依存翻訳に関与する要因を特定する.
- PTIシグナル伝達とタンパク質合成の規制との関係を確立する.
主な方法:
- PTI中のmRNAデカッピングの分析
- 内部リボソームエントリーサイト (IRES) としてR-モチーフ機能の識別.
- ポリA結合タンパク質 (PABP) と翻訳開始因子 (eIFiso4G,eIF4G) の相互作用を調査する.
- ミトゲン活性化タンパク質キナーゼ3と6 (MPK3/6) のリン酸化効果の研究
主要な成果:
- PTIはmRNAの解離を誘導し,一般的な翻訳を阻害する.
- Rモチーフを含む防衛mRNAは,IRES活動によって選択的に翻訳される.
- PABPは,R-モチーフの翻訳では,eIFiso4GよりもeIF4Gと優先的に関連付けられています.
- MPK3/ 6のリン酸化は,R-モチーフへのPABP結合を強化し,eIFiso4G媒介による翻訳を促進する.
結論:
- 植物では,PTI中に選択的防御mRNA翻訳のためにR-モチーフ/PABP/eIFiso4Gモジュールを使用しています.
- この経路は,GCN2/eIF2αを回避して,PTIシグナル伝達とタンパク質合成の調節を結びつける.
- PABP/R-モチーフの翻訳モジュールは,エウカリオートにおけるストレストランスラトームの再プログラムに保存された役割を果たす可能性がある.
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