Kolkman Annemieke, Daran-Lapujade Pascale, Fullaondo Asier, Olsthoorn Maurien M A, Pronk Jack T, Slijper Monique, Heck Albert J R
Department of Biomolecular Mass Spectrometry, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands.
Mol Syst Biol. 2006;2:2006.0026. doi: 10.1038/msb4100069. Epub 2006 May 16.
We compared the response of Saccharomyces cerevisiae to carbon (glucose) and nitrogen (ammonia) limitation in chemostat cultivation at the proteome level. Protein levels were differentially quantified using unlabeled and 15N metabolically labeled yeast cultures. A total of 928 proteins covering a wide range of isoelectric points, molecular weights and subcellular localizations were identified. Stringent statistical analysis identified 51 proteins upregulated in response to glucose limitation and 51 upregulated in response to ammonia limitation. Under glucose limitation, typical glucose-repressed genes encoding proteins involved in alternative carbon source utilization, fatty acids beta-oxidation and oxidative phosphorylation displayed an increased protein level. Proteins upregulated in response to nitrogen limitation were mostly involved in scavenging of alternative nitrogen sources and protein degradation. Comparison of transcript and protein levels clearly showed that upregulation in response to glucose limitation was mainly transcriptionally controlled, whereas upregulation in response to nitrogen limitation was essentially controlled at the post-transcriptional level by increased translational efficiency and/or decreased protein degradation. These observations underline the need for multilevel analysis in yeast systems biology.
我们在恒化器培养中，在蛋白质组水平上比较了酿酒酵母对碳（葡萄糖）和氮（氨）限制的反应。使用未标记和15N代谢标记的酵母培养物对蛋白质水平进行差异定量。共鉴定出928种蛋白质，其涵盖了广泛的等电点、分子量和亚细胞定位。严格的统计分析确定了51种因葡萄糖限制而上调的蛋白质和51种因氨限制而上调的蛋白质。在葡萄糖限制条件下，编码参与替代碳源利用、脂肪酸β-氧化和氧化磷酸化的蛋白质的典型葡萄糖抑制基因的蛋白质水平升高。因氮限制而上调的蛋白质主要参与替代氮源的清除和蛋白质降解。转录水平和蛋白质水平的比较清楚地表明，对葡萄糖限制的上调主要受转录控制，而对氮限制的上调基本上在转录后水平上通过提高翻译效率和/或降低蛋白质降解来控制。这些观察结果强调了酵母系统生物学中进行多层次分析的必要性。
