哺乳類のSIRT1はフォークヘッドの転写因子を抑制する
Maria Carla Motta1, Nullin Divecha, Madeleine Lemieux
1Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Cell
|February 26, 2004
まとめ
哺乳類のSIRT1は,Foxo3aのようなフォークヘッド因子を脱酸化し,その活動を抑制し,アポトーシスを減少させます. これは酵母と虫と対照的に,カロリー制限が長寿を促進する方法を説明する可能性がある.
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
- 老化に関する研究
背景:
- NAD依存型脱酸化酵素SIR2とフォークヘッドの転写因子は,モデル生物の寿命を調節する.
- SIR2とフォークヘッドタンパク質は,C. elegansで遺伝的に相互作用し,寿命に影響を与えます.
研究 の 目的:
- 哺乳類のSIR2オーソログ (SIRT1) と哺乳類のフォークヘッド転写因子 (例えば,Foxo3a) の相互作用を調査する.
- フォークヘッドの活性を調節するSIRT1の役割とその老化とアポトーシスの影響を解明する.
主な方法:
- SIRT1.1によるFoxo3aの脱エチル化を示すための生化学分析.
- フォークヘッド因子の転写活動に対するSIRT1の影響の分析.
- 哺乳類の発見とC. elegansの遺伝子相互作用の比較.
主要な成果:
- SIRT1は,FOXO3aを含む哺乳類のフォークヘッド転写因子の活性を脱酸化し,抑制する.
- フォークヘッドタンパク質のSIRT1媒介阻害は,フォークヘッド依存性アポトーシスを減少させます.
- また,SIRT1は,フォークヘッド因子に対する効果に類似して,腫瘍抑制剤p53を抑制する.
結論:
- 哺乳類のSIRT1はフォークヘッドの転写因子を否定的に調節し,C. elegans.で観察された遺伝子の相互作用に反対します.
- SIRT1によるフォークヘッドタンパク質とp53のダウンレギュレーションは,カロリー制限のような条件下で寿命延長に貢献する可能性があります.
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