Department of Biology, College of Arts and Sciences, Drexel University, Philadelphia, PA, USA.
Cell Cycle. 2012 Oct 1;11(19):3679-90. doi: 10.4161/cc.21944. Epub 2012 Aug 30.
Glutamine (Gln) and glucose (Glc) represent two important nutrients for proliferating cells, consistent with the observations that oncogenic processes are associated with enhanced glycolysis and glutaminolysis. Gln depletion and Glc depletion have been shown to trigger growth arrest and eventually cell death. Solid tumors often outgrow the blood supply, resulting in ischemia, which is associated with hypoxia and nutrient insufficiency. Whereas oxygen-sensing and adaptive mechanisms to hypoxia have been well-studied, how cells directly sense and respond to Gln and Glc insufficiency remains unclear. Using mRNA profiling techniques, we compared the gene expression profiles of acute Gln-depleted cells, Glc-depleted cells and cells adapted to Gln depletion. Here we report the global changes of the gene expression in those cells cultured under the defined nutrient conditions. Analysis of mRNA profiling data revealed that Gln and Glc depletion triggered dramatic gene expression reprogramming. Either Gln or Glc deletion leads to changes of the expression of cell cycle genes, but these conditions have distinctive effects on transcription regulators and gene expression profiles. Moreover, Gln and Glc depletion triggered distinguishable ER-stress responses. The gene expression patterns support that Gln and Glc have distinctive metabolic roles in supporting cell survival and proliferation, and cells use different mechanisms to sense and respond to Gln and Glc insufficiency. Our mRNA profiling database provides a resource for further investigating the nutrient-sensing mechanisms and potential effects of Glc and Gln abundance on the biological behaviors of cells.
谷氨酰胺(Gln)和葡萄糖(Glc)是增殖细胞的两种重要营养素,这与致癌过程与增强糖酵解和谷氨酰胺分解一致的观察结果是一致的。已表明 Gln 耗尽和 Glc 耗尽会触发生长停滞,最终导致细胞死亡。实体瘤通常会超出血液供应,导致缺血,这与缺氧和营养不足有关。虽然已经对氧感应和缺氧适应机制进行了深入研究,但细胞如何直接感知和响应 Gln 和 Glc 不足仍然不清楚。我们使用 mRNA 谱技术比较了急性 Gln 耗尽细胞、Gln 耗尽细胞和适应 Gln 耗尽的细胞的基因表达谱。在这里,我们报告了在这些细胞在定义的营养条件下培养时的基因表达的全局变化。对 mRNA 谱数据的分析表明,Gln 和 Glc 耗尽会引发剧烈的基因表达重编程。Gln 或 Glc 的缺失都会导致细胞周期基因的表达变化,但这些条件对转录调节剂和基因表达谱有独特的影响。此外,Gln 和 Glc 耗尽会引发可区分的 ER 应激反应。基因表达模式表明,Gln 和 Glc 在支持细胞存活和增殖方面具有独特的代谢作用,细胞使用不同的机制来感知和响应 Gln 和 Glc 不足。我们的 mRNA 谱数据库为进一步研究营养感应机制以及 Glc 和 Gln 丰度对细胞生物学行为的潜在影响提供了资源。