IGF-II mRNA的成长依赖翻译由一种对拉帕素敏感通路进行
F C Nielsen1, L Ostergaard, J Nielsen
1Department of Clinical Biochemistry, Rigshospitalet, Copenhagen O, Denmark.
Nature
|September 28, 1995
概括
人类IGF-II基因产生两个主要的mRNA类型. 一个小的mRNA连续制造前-pro-IGF-II,而一个主要的mRNA则通过特定的激酶通路进行翻译调节.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
背景情况:
- 胰岛素类生长因子 (IGF-II) 对胎儿生长至关重要.
- 人类IGF-II基因产生多个mRNA转录,具有不同的5'未翻译区域 (5'UTR).
- 以前,一个4.8kb的mRNA被确定用于IGF-II前合成,一个6.0kb的mRNA被发现未被翻译并存储在100S核糖蛋白颗粒中.
研究的目的:
- 为了研究6.0-kb IGF-II mRNA的翻译调节.
- 阐明参与6.0-kb IGF-II mRNA的调动和翻译的信号通路.
主要方法:
- 分散的指数增长细胞的细胞培养.
- 用拉帕米辛和阿尼索米辛治疗以研究翻译调节.
- 对mRNA调动和翻译的分析.
主要成果:
- 6.0-kb IGF-II mRNA 在指数增长的细胞中被选择性地调动和翻译.
- 拉帕米辛抑制,而阿尼索米辛模仿,6.0-kb的mRNA的翻译.
- 这表明p70S6k/85S6k激酶信号通路的调节.
结论:
- 4.8kb的IGF-II mRNA确保了构成性IGF-II前的产生.
- 6.0kb的IGF-II mRNA代表了一个经过转录调节的物种.
- 该p70S6k/85S6k通路控制主要IGF-IImRNA转录的翻译.
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