Construction of gene expression profiles for anoxia-reoxygenation in Arabidopsis

To understand how plants respond to anoxia-reoxygenation, we have employed a global microarray expression profiling as a basic platform to characterize genes with the potential to mediate the recovery responses in Arabidopsis. 7-day-old seedlings were trated with 4hr and 8hr anoxia, and then reoxygenated in air for 0, 0.5, 1, 3, 6 hrs. Genes changed in both condition were designated as reoxygenation-regulated genes. They included the genes in ROS detoxification, dehydration, metabolic process, and many other responses. Interestingly, ethylene was also involved in this recovery process. We further adopted ein2-5 and ein3eil1 microarray to investigate ethylene signaling. Our results showed ethylene partially regulate reoxygenation regulated genes and is reruired for plant survival in reoxygenation. Genes expression during anoxia-reoxygenation in Arabidopsis seedlings was measured at 0, 0.5, 1, 3, 6 hours after anoxia treatment, and normal condition before anoxia. Three independent experiments were performed at each time (Nor, 0, 0.5, 1, 3, 6) under 4hr anoxia-reoxygenation condition by using Col-0, ein2-5, and ein3eil1. Four independent experiments were performed at each time (Nor, 0, 0.5, 1, 3, 6) under 8hr anoxia-reoxygenation condition by using Col-0.

为解析植物对缺氧-复氧胁迫的响应机制，本研究采用全基因组微阵列（microarray）表达谱作为核心研究平台，对拟南芥（Arabidopsis）中潜在介导复氧恢复响应的基因开展系统表征。选取生长7天的幼苗，分别施加4小时与8小时缺氧处理，随后将幼苗置于正常空气中复氧0、0.5、1、3、6小时。在两种缺氧时长处理下均出现表达差异的基因，被定义为复氧调控基因，其功能涵盖活性氧（Reactive Oxygen Species, ROS）解毒、脱水应答、代谢进程及诸多其他胁迫响应途径。值得注意的是，乙烯亦参与该复氧恢复过程。本研究进一步利用ein2-5与ein3eil1突变体的微阵列数据，探究乙烯信号通路在其中的调控作用。研究结果表明，乙烯可部分调控复氧应答基因的表达，且为植物在复氧阶段的存活所必需。本研究检测了拟南芥幼苗在缺氧-复氧过程中的基因表达水平：在4小时缺氧-复氧条件下，以Col-0野生型、ein2-5及ein3eil1突变体为材料，对正常生长状态、缺氧处理后0、0.5、1、3、6小时共6个时间点均设置3次独立生物学重复；在8小时缺氧-复氧条件下，以Col-0野生型为材料，对上述6个时间点均设置4次独立生物学重复。