Krev-1タンパク質p21rap1に特異的なGTPアゼ活性化タンパク質の分子クローン化
B Rubinfeld1, S Munemitsu, R Clark
1Cetus Corporation, Emeryville, California 94608.
Cell
|June 14, 1991
まとめ
研究者らは,Rap1/Krev-1.に特異的な新しいGTPase活性化タンパク質 (GAP) を特定した. このrap1GAPは広く発現しないため,胎児組織や特定の腫瘍細胞系においてより多く発現している.
科学分野:
- 分子生物学は分子生物学である.
- 細胞シグナル伝達 細胞信号伝達
背景:
- rap1/Krev-1遺伝子は,癌変異抑制に関与するras関連タンパク質をコードする.
- GTP酶活性化タンパク質 (GAPs) は,rasに関連するタンパク質の活動を調節する.
研究 の 目的:
- rap1/Krev-1遺伝子製品に特異的なGTPase活性化タンパク質 (GAP) を特定し,特徴づけること.
- この新しいラップ1GAP.の表現パターンを決定するために.
主な方法:
- 牛の脳から88 kDaのGTPase活性化タンパク質 (GAP) の浄化.
- 部分アミノ酸配列を用いて,人間の脳図書館から3.3kbのcDNAを分離した.
- 昆虫のSf9細胞におけるcDNAの発現.
- 表現プロファイリングのための北方および西部のブラッティング分析.
主要な成果:
- A rap1GAPを精製し,p21rap1 GTPaseに対する特定の活性が確認されました.
- 隔離されたcDNAは,昆虫の細胞で機能的なrap1GAP (85-95 kDa) を表現した.
- rap1GAPの推論されたアミノ酸配列は,既知のras-specific GAPsとのホモロジーを示さなかった.
- rap1GAPの発現は制限され,胎児組織と特定の腫瘍細胞系 (SK-NEP-1,SK-MEL-3) で最も高いレベルであることが判明しました.
結論:
- 新しいRAP1GAPが特定され,特徴づけられました.
- この rap1GAPは,p21rap1.1を規制する上で特別な役割を果たしています.
- 制限された発現パターンは,発達における,そして潜在的に腫瘍発生における,特異的な機能を示唆している.
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