通过外部添加的酸性纤维细胞生长因子进行信号传导的双模式
A Wiedłocha1, P O Falnes, I H Madshus
1Institute for Cancer Research, Norwegian Radium Hospital, Montebello, Oslo.
Cell
|March 25, 1994
概括
酸性纤维细胞生长因子 (aFGF) 融合蛋白刺激了缺乏aFGF受体的细胞中的DNA合成. 进入细胞核对于aFGF促进DNA合成至关重要,这表明双重信号通路.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 酸性纤维细胞生长因子 (aFGF) 是细胞增殖和存活的关键调节者.
- 双菌毒素 (DT) 是一种强大的毒素,通过受体介导的内细胞分裂进入细胞.
- 了解生长因子信号通路对于开发向疗法至关重要.
研究的目的:
- 研究aFGF的信号机制,特别是细胞表面受体与细胞内运输的作用.
- 为了确定aFGF和DT的融合蛋白是否可以绕过细胞表面受体的信号传递要求.
- 阐明核转位对aFGF介导的DNA合成的贡献.
主要方法:
- 一种aFGF-二甲状腺毒素融合蛋白的构建和应用.
- 使用抗毒素和aFGF受体缺乏细胞系 (NIH 3T3).
- 评估对aFGF和融合蛋白的反应中的DNA合成和氨酸酸化.
主要成果:
- 该aFGF-DT融合蛋白刺激了缺乏功能性aFGF受体但具有DT受体的细胞中的DNA合成.
- 在NIH 3T3细胞中 (缺乏DT受体,但具有aFGF受体),aFGF和融合蛋白都诱导了氨酸酸化.
- 只有本地aFGF,而不是融合蛋白,转移到核中并刺激NIH 3T3细胞中的DNA合成.
结论:
- 由aFGF进行的细胞信号传递涉及细胞表面受体介导的通路和细胞内运输.
- aFGF的核进入对于刺激DNA合成至关重要.
- 这项研究强调了控制生长因子信号和细胞反应的复杂机制.
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