Time resolved ribosome profiling study of oxygen and glucose deprivation of rat pheochromocytoma cells

Oxygen and glucose metabolism plays a pivotal role in many (patho)physiological conditions. In particular, oxygen and glucose deprivation (OGD) occurs during ischemia and stroke, resulting in extensive tissue injury and cell death. We applied time-resolved ribosome profiling technique to assess early events at the level of gene expression in rat pheochromocytoma PC12 cells during short-term OGD. Most substantial alterations in transcripts levels and their translation were seen to occur in the first 20 minutes of OGD. The rapid adaptation of translation apparatus to OGD is global and involves altered elongation and initiation rates. We also observed salient and reproducible alterations in ribosome densities of individual mRNAs such as increased translation of particular upstream Open Reading Frames (uORFs); induced site-specific arrests of the ribosomes and synthesis of extended protein isoforms.氧和葡萄糖代谢在诸多（病理）生理状态中发挥关键作用。氧糖剥夺（Oxygen and glucose deprivation, OGD）常发生于缺血与脑卒中进程中，可引发广泛的组织损伤与细胞死亡。本研究采用时间分辨核糖体谱技术，对短期氧糖剥夺（OGD）过程中大鼠嗜铬细胞瘤PC12细胞的基因表达水平早期事件展开评估。结果显示，转录本水平及其翻译的最显著变化均发生在OGD的前20分钟内。翻译机器对OGD的快速适应性响应具有全局性，涉及延伸速率与起始速率的改变。此外，我们还观察到单个mRNA的核糖体密度出现显著且可重复的变化，例如特定上游开放阅读框（uORFs）的翻译增强、核糖体的位点特异性停滞以及延长型蛋白质异构体的合成。