García-Martínez José, Aranda Agustín, Pérez-Ortín José E
Departamento de Bioquímica y Biología Molecular, Universitat de València, Burjassot, Spain.
Mol Cell. 2004 Jul 23;15(2):303-13. doi: 10.1016/j.molcel.2004.06.004.
Most studies of eukaryotic gene regulation have been done looking at mature mRNA levels. Nevertheless, the steady-state mRNA level is the result of two opposing factors: transcription rate (TR) and mRNA degradation. Both can be important points to regulate gene expression. Here we show a new method that combines the use of nylon macroarrays and in vivo radioactive labeling of nascent RNA to quantify TRs, mRNA levels, and mRNA stabilities for all the S. cerevisiae genes. We found that during the shift from glucose to galactose, most genes undergo drastic changes in TR and mRNA stability. However, changes in mRNA levels are less pronounced. Some genes, such as those encoding mitochondrial proteins, are coordinately regulated in mRNA stability behaving as decay regulons. These results indicate that, although TR is the main determinant of mRNA abundance in yeast, modulation of mRNA stability is a key factor for gene regulation.
大多数关于真核基因调控的研究都是针对成熟mRNA水平进行的。然而，稳态mRNA水平是两个相反因素的结果：转录速率（TR）和mRNA降解。这两者都可能是调节基因表达的重要环节。在这里，我们展示了一种新方法，该方法结合使用尼龙宏阵列和新生RNA的体内放射性标记来量化所有酿酒酵母基因的转录速率、mRNA水平和mRNA稳定性。我们发现，在从葡萄糖向半乳糖转变的过程中，大多数基因的转录速率和mRNA稳定性都发生了剧烈变化。然而，mRNA水平的变化不太明显。一些基因，如那些编码线粒体蛋白的基因，在mRNA稳定性方面受到协同调节，表现为衰变调控子。这些结果表明，虽然转录速率是酵母中mRNA丰度的主要决定因素，但mRNA稳定性的调节是基因调控的关键因素。
