基因表达是循环的:mRNA降解的因素也促进了mRNA合成
Gal Haimovich1, Daniel A Medina, Sebastien Z Causse
1Department of Molecular Microbiology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel.
Cell
|May 28, 2013
概括
大多数酵母mRNA都通过细胞质5'-至-3'-衰变途径降解. 这个途径中的缺陷令人惊地导致转录下调,揭示了一个循环基因表达过程.
科学领域:
- 分子生物学分子生物学
- 基因规则 基因规则
- 酵母遗传学 酵母遗传学
背景情况:
- 基因表达调节依赖于保持精确的mRNA水平.
- mRNA水平是由合成和衰变之间的平衡决定的.
- 细胞质 5 o3 ext {路径} (衰变) 是一种主要的mRNA降解路径.
研究的目的:
- 为了研究mRNA水平对衰变途径中扰动的稳定性.
- 阐明mRNA水平稳定性背后的机制.
- 探索细胞质mRNA衰变之外的衰变组分的潜在作用.
主要方法:
- 酵母菌菌株中mRNA水平的分析,其中一些成分的衰变有缺陷.
- 研究细胞下定位和染色体协会的衰变蛋白质.
- 测试以评估核衰变对转录的一些组件功能的影响.
主要成果:
- mRNA水平对衰变途径缺陷具有惊人的强度.
- 衰变组件中的缺陷引发了mRNA转录的下调.
- 衰变组分在细胞质和核之间穿,与转录起始点附近的染色质结合,以刺激启动和延长.
结论:
- 衰变体在mRNA衰变和转录调节中起着双重作用.
- 转录中的衰变体的核功能与其通过蛋白质穿在mRNA衰变中的细胞质作用有关.
- 基因表达表现出连接转录和mRNA降解的循环调节机制.
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