新生チェーンとの非効率なSRP相互作用は,mRNA品質管理経路を誘発する
Andrey L Karamyshev1, Anna E Patrick1, Zemfira N Karamysheva1
1Department of Physiology, UT Southwestern Medical Center at Dallas, Dallas, TX 75390, USA.
Cell
|January 21, 2014
まとめ
細胞システムは,有毒なタンパク質の蓄積を防ぐ. 分泌タンパク質の欠陥により,Argonaute2 (Ago2) がmRNAを分解し,新しい翻訳性品質管理メカニズムを通じて異常なタンパク質の生成を防ぐ.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- タンパク質ホメオスタシス
背景:
- 誤った折りたたまれたタンパク質は,細胞システムがその蓄積を防ぐことができなければ,細胞毒性になる可能性があります.
- 分泌タンパク質は,適切な折り畳みと転位のために特定の経路を必要とします.
- 既存の品質管理メカニズムは,主にタンパク質の折り畳みと分解に焦点を当てています.
研究 の 目的:
- 分泌タンパク質の欠陥がmRNAおよびタンパク質発現を減少させる新しいメカニズムを発見すること.
- 異常分泌タンパク質合成への反応におけるアルゴナウト2 (Ago2) の役割を明らかにする.
- 偏差タンパク質生産 (RAPP) を予防的に規制する新しい翻訳品質管理経路の特徴づけ.
主な方法:
- 新生分泌タンパク質鎖,信号認識粒子 (SRP),およびリボソームの出口部位にあるArgonaute2 (Ago2) の間の相互作用を調査した.
- Argonaute2 (Ago2) のノックダウンと過剰表現の実験を活用して,mRNAの分解におけるその役割を評価した.
- SRP54のノックダウンを行い,分泌タンパク質mRNAの安定性への影響を評価しました.
主要な成果:
- SRPに結合できない変異信号配列は,Ago2との新生チェーン接触につながります.
- この相互作用は,特に変異性分泌タンパク質mRNAsの分解を誘発する.
- シグナルシーケンスの突然変異の重さは,Ago2の接近とmRNAの退化と相関する;Ago2のノックダウンが退化を抑制し,Ago2の過剰表現またはSRP54のノックダウンがそれを促進する.
結論:
- 変異性タンパク質生産を予防的に制御する (RAPP) という新しい翻訳的品質管理メカニズムが特定されました.
- Ago2は,異常な分泌タンパク質をコードするmRNAを認識し,分解する上で重要な役割を果たします.
- この経路は,mRNAレベルでのタンパク質の生産を制御するための,以前は評価されていなかった一般的なメカニズムを表しています.
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