NFE2L1/Nrf1はペプチド:N-グリカナーゼを介した配列編集後に共活性化因子複合体を形成し、プロテアソーム機能不全を軽減する
Yukiko Yoshida1, Meari Okada1, Naoko Arai1
1Laboratory of Protein Metabolism, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan.
まとめ
核内因子赤血球2様1(Nrf1)は、転写因子にとってユニークなプロセスである配列編集によって活性化される。この編集はプロテアソーム遺伝子発現と細胞生存に不可欠であるが、その恒常的な活性化は毒性をもたらしうる。
科学分野:
- 分子生物学
- 細胞生物学
- 生化学
背景:
- 核内因子赤血球2様1(NFE2L1/Nrf1)は、プロテアソーム遺伝子を調節するER関連転写因子である。
- Nrf1は、ペプチド:N-グリカナーゼ(NGLY1)が関与するプロセスである配列編集によって転写活性化されるという点でユニークである。
研究 の 目的:
- 配列編集がNrf1の転写活性を調節するメカニズムを解明する。
- N結合型糖鎖修飾部位の編集がNrf1の機能および細胞応答に果たす役割を調査する。
主な方法:
- HeLa細胞におけるヒトNrf1のN結合型糖鎖修飾部位の配列編集を検討した。
- Nrf1のタンパク質相互作用およびクロマチン結合を調査した。
- Nrf1変異体が細胞増殖に及ぼす影響を分析した。
主要な成果:
- Nrf1のAsn574部位の配列編集は、プロテアソーム遺伝子発現、宿主細胞因子C1およびO-GlcNAc転移酵素との相互作用に不可欠である。
- 他のN結合型糖鎖修飾部位の編集は、共活性化因子CREBBP/EP300との相互作用を促進し、転写活性を高める。
- プロテアーゼ様処理またはNGLY1編集の模倣によるNrf1の恒常的な活性化は、細胞増殖を低下させ、細胞毒性を示唆した。
結論:
- Nrf1の活性化は、プロテアソームストレス下での細胞生存に不可欠な、調節されたオンデマンドプロセスである。
- Nrf1の配列編集は、転写活性および共活性化因子複合体との相互作用を制御する主要な調節メカニズムである。
- Nrf1の制御されない活性化は細胞毒性につながる可能性があり、その制御された発現の重要性を強調している。
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