Myc と C/EBP アルファによるアディポゲネシスの相互調節
1Molecular Biology Research Program, Henry Ford Hospital, Detroit, MI 48202.
Science (New York, N.Y.)
|April 17, 1992
まとめ
Mycタンパク質の高いレベルは,3T3-L1細胞における脂肪細胞の分化を阻害する. しかし,C/EBPアルファは,このブロックを克服し,アディポゲネシスの重要なレギュレータを明らかにすることができます.
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
- バイオケミストリー バイオケミストリー
背景:
- 3T3-L1アディポブラストは,脂肪細胞の微分化を研究するための一般的なモデルです.
- 転写因子c-Mycは,細胞増殖と分化に作用することが知られている.
- CCAAT/エンハンサー結合タンパク質アルファ (C/EBPアルファ) は,アディポゲネシスの重要な調節体である.
研究 の 目的:
- 3T3-L1細胞におけるアディポゲネシスの抑制におけるc-Mycの役割を調査する.
- 脂肪細胞の分化過程におけるc-MycとC/EBPαの関係を決定する.
- Myc媒介によるアディポゲネシスの阻害の基礎となる分子メカニズムを解明する.
主な方法:
- 3T3-L1アディポブラストをc-MycとC/EBPααをコードする遺伝子で変異させる.
- アディポサイト形態と遺伝子発現の分析.
- 差別化マーカーの評価.
主要な成果:
- 3T3-L1細胞におけるc-Mycの過剰発現は,アディポサイトへの末端分化を阻害した.
- c-Myc発現は,アディポゲネシスの重要な要因であるC/EBPアルファの誘導を阻害した.
- C/EBPアルファの強制発現は,c-Myc.によって引き起こされた分化ブロックを救出しました.
結論:
- c-Mycは,C/EBPアルファ誘導を抑制することによって,アディポゲネシスの負の調節剤として作用します.
- C/EBPアルファは,Myc誘発による脂肪細胞分化阻害を克服できる重要な媒介体である.
- MycとC/EBPαは,アディポゲネシスの分子制御における重要なレギュレータである.
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