Cambridge Systems Biology Centre & Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, UK.
BMC Biol. 2010 May 24;8:68. doi: 10.1186/1741-7007-8-68.
To elucidate the biological processes affected by changes in growth rate and nutrient availability, we have performed a comprehensive analysis of the transcriptome, proteome and metabolome responses of chemostat cultures of the yeast, Saccharomyces cerevisiae, growing at a range of growth rates and in four different nutrient-limiting conditions.
We find significant changes in expression for many genes in each of the four nutrient-limited conditions tested. We also observe several processes that respond differently to changes in growth rate and are specific to each nutrient-limiting condition. These include carbohydrate storage, mitochondrial function, ribosome synthesis, and phosphate transport. Integrating transcriptome data with proteome measurements allows us to identify previously unrecognized examples of post-transcriptional regulation in response to both nutrient and growth-rate signals.
Our results emphasize the unique properties of carbon metabolism and the carbon substrate, the limitation of which induces significant changes in gene regulation at the transcriptional and post-transcriptional level, as well as altering how many genes respond to growth rate. By comparison, the responses to growth limitation by other nutrients involve a smaller set of genes that participate in specific pathways. See associated commentary http://www.biomedcentral.com/1741-7007/8/62.
为了阐明生长速率和营养供应变化影响的生物过程,我们对在不同生长速率和四种不同营养限制条件下生长的酵母酿酒酵母恒化培养物的转录组、蛋白质组和代谢组应答进行了全面分析。
我们在测试的四种营养限制条件中的每一种中都发现了许多基因表达的显著变化。我们还观察到几个对生长速率变化和每个营养限制条件都有不同反应的过程。这些过程包括碳水化合物储存、线粒体功能、核糖体合成和磷酸盐转运。将转录组数据与蛋白质组测量相结合,使我们能够识别出以前未被识别的对营养和生长速率信号的转录后调控的例子。
我们的结果强调了碳代谢和碳底物的独特性质,碳底物的限制在转录和转录后水平上引起基因调控的显著变化,并改变了许多基因对生长速率的反应。相比之下,对其他营养物质生长限制的反应涉及一组较小的基因,它们参与特定的途径。请参见相关评论 http://www.biomedcentral.com/1741-7007/8/62。