誘導されたNIH/3T3細胞の成長にはRaf-1タンパク質キナーゼが必要である
W Kolch1, G Heidecker, P Lloyd
1Laboratory of Viral Carcinogenesis, NIH/NCI, Frederick Cancer Research and Development Center, Maryland 21702-1201.
Nature
|January 31, 1991
まとめ
Raf-1キナーゼは,細胞成長シグナル伝達に不可欠です. Raf-1の機能を阻害すると,増殖と変異を阻害し,成長因子受容体とras腫瘍遺伝子の下流の役割を確認します.
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
- 腫瘍生成 (オンコゲネシス) について
背景:
- Raf-1タンパク質キナーゼは,成長因子媒介信号伝導の重要な調節因子である.
- その至るところに存在する表現と増殖における役割は,受容体信号伝達経路における重要性を示唆しています.
研究 の 目的:
- Raf-1キナーゼが血清およびTPA調節されたNIH/3T3細胞成長に不可欠であるかどうかを判断する.
- 成長因子受容体と腫瘍遺伝子の下流の信号伝導におけるRaf-1の役割を調査する.
主な方法:
- c-raf-1アンチセンセスのRNAを用いてRaf-1機能を抑制する.
- キナーゼ欠陥c-raf-1変異体 (craf301) と規制ドメイン断片 (HCR) の発現.
- 血清またはTPAによって誘発されたNIH/3T3細胞増殖およびDNA複製の評価.
主要な成果:
- c-raf-1に対するAntisense RNAはNIH/3T3細胞増殖を妨害し,RAF変形細胞を逆転させた.
- 反感覚RNAまたはキナーゼ欠陥変異体によるRaf-1機能の抑制は,血清,TPA,ras腫瘍遺伝子が誘発した増殖と変異を阻害します.
- 減少したRafタンパク質レベルは,減少したDNA複製と相関しています.
結論:
- Raf-1キナーゼは,血清成長因子受容体,タンパク質キナーゼC,およびrasによって開始される経路における重要な信号変換器として機能します.
- Raf-1は,成長信号と腫瘍性変異に対する細胞の反応を媒介するために重要である.
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