提升的tRNA(iMet) 合成可以驱动细胞增殖和瘤转化
Lynne Marshall1, Niall S Kenneth, Robert J White
1Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
Cell
|April 9, 2008
概括
提升的RNA聚合酶III (polIII) 转录,特别是增加转移RNA (tRNA) 合成,驱动细胞增殖和瘤转化. 这表明tRNA的产生是瘤发育的关键因素.
科学领域:
- 分子生物学分子生物学
- 癌症研究 癌症研究
- 细胞生物学 细胞生物学
背景情况:
- 转化和瘤细胞表现出增强的蛋白质合成和增加的RNA聚合酶III (polIII) 产物,如tRNA和5SrRNA.
- 在细胞转化中放松的pol III转录的精确作用仍然不完全理解.
研究的目的:
- 调查上调的pol III转录是否直接导致瘤转化.
- 为了确定特定的pol III产品,如tRNAs,对细胞增殖和转化的影响.
主要方法:
- 产生可诱导的细胞系,表达pol III特异的转录因子 Brf1.1.
- 操纵Brf1水平以特别改变tRNA和5SrRNA合成.
- 在体内评估细胞增殖,瘤转化和瘤形成.
主要成果:
- Brf1诱导导致tRNA和5SrRNA水平增加,促进细胞增殖和瘤转化.
- Brf1的耗尽抑制了转化,突出了它的重要作用.
- 过度表达tRNA ((iMet),一个关键的pol III产物,足以刺激小鼠的增殖和诱导瘤形成.
结论:
- 由pol III转录驱动的提升的tRNA合成,是细胞转换的重要促进者.
- 准pol III活性或tRNA合成可能代表癌症的新疗法策略.
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