c-Fosタンパク質はc-Jun/AP-1と相互作用し,AP-1反応性遺伝子の転写を刺激する
1Department of Pharmacology, School of Medicine, University of California, San Diego, La Jolla 92093.
Cell
|August 12, 1988
まとめ
Fosタンパク質は,AP-1転写因子と相互作用することによって,転写トランス活性化剤として作用します. この相互作用は,遺伝子発現を刺激するために極めて重要であり,AP-1を強調しています.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝子規制 遺伝子規制
- 転写因子 トランスクリプション・ファクター
背景:
- c-fos遺伝子産物であるFosは,転写トランス活性化剤としての役割について調査されています.
- 細胞系は,Fos機能の研究のために誘導可能なMT-fosキメリック遺伝子を発現するように設計されました.
- 以前の研究では,Fosが遺伝子発現の調節に関与していることが示唆されていた.
研究 の 目的:
- Fosが転写トランス活性化剤として機能できるかどうかを判断する.
- Fosが遺伝子発現を媒介するメカニズムを解明する.
- Fos媒介活性化におけるAP-1転写因子の役割を調査する.
主な方法:
- 金属誘導性MT-fos遺伝子による細胞系 (3T3MTfosとF9MTfos) の安定した変異.
- レポーター遺伝子アッセイは,AP-1応答性遺伝子トランス活性化を測定する.
- c-Jun/AP-1発現ベクトルと共免疫プレシピテーションアッセイによるトランスフィクション.
主要な成果:
- Fos発現は,3T3MTfos細胞におけるAP-1レポーター遺伝子のトランス活性化を誘発した.
- Fos誘導は,AP-1が欠けているF9MTfos細胞のレポーター遺伝子を活性化しませんでした.
- F9MTfos細胞におけるc-Jun/AP-1発現の回復により,Fos媒介型トランス活性化が再確立されました.
- Fosは,タンパク質複合体におけるc-Jun/AP-1 (FAP p39) と結合することが判明した.
結論:
- Fosは,遺伝子発現を間接的に刺激するトランス作用因子として作用します.
- Fosの活性には,配列特異の転写因子AP-1との相互作用が必要です.
- AP-1によるcis要素の認識は,Fos媒介遺伝子発現の前提条件である.
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