Wang Gang-Feng, Li Wen-Qiang, Li Wen-Yan, Wu Guo-Li, Zhou Cong-Yi, Chen Kun-Ming
State Key Laboratory of Crop Stress Biology in Arid Areas, College of Life Sciences, Northwest A&F University, Yangling 712100, Shaanxi, China.
Int J Mol Sci. 2013 Apr 29;14(5):9440-58. doi: 10.3390/ijms14059440.
Plasma membrane NADPH oxidases (Noxs) are key producers of reactive oxygen species under both normal and stress conditions in plants. We demonstrate that at least eleven genes in the genome of rice (Oryza sativa L.) were predicted to encode Nox proteins, including nine genes (OsNox1-9) that encode typical Noxs and two that encode ancient Nox forms (ferric reduction oxidase 1 and 7, OsFRO1 and OsFRO7). Phylogenetic analysis divided the Noxs from nine plant species into six subfamilies, with rice Nox genes distributed among subfamilies I to V. Gene expression analysis using semi-quantitative RT-PCR and real-time qRT-PCR indicated that the expression of rice Nox genes depends on organs and environmental conditions. Exogenous calcium strongly stimulated the expression of OsNox3, OsNox5, OsNox7, and OsNox8, but depressed the expression of OsFRO1. Drought stress substantially upregulated the expression of OsNox1-3, OsNox5, OsNox9, and OsFRO1, but downregulated OsNox6. High temperature upregulated OsNox5-9, but significantly downregulated OsNox1-3 and OsFRO1. NaCl treatment increased the expression of OsNox2, OsNox8, OsFRO1, and OsFRO7, but decreased that of OsNox1, OsNox3, OsNox5, and OsNox6. These results suggest that the expression profiles of rice Nox genes have unique stress-response characteristics, reflecting their related but distinct functions in response to different environmental stresses.
质膜NADPH氧化酶（Noxs）是植物在正常和胁迫条件下活性氧的关键产生者。我们证明，水稻（Oryza sativa L.）基因组中至少有11个基因被预测编码Nox蛋白，其中包括9个编码典型Noxs的基因（OsNox1 - 9）和2个编码古老Nox形式的基因（铁还原氧化酶1和7，OsFRO1和OsFRO7）。系统发育分析将来自9种植物的Noxs分为6个亚家族，水稻Nox基因分布在亚家族I至V中。使用半定量RT-PCR和实时定量RT-PCR进行的基因表达分析表明，水稻Nox基因的表达取决于器官和环境条件。外源钙强烈刺激OsNox3、OsNox5、OsNox7和OsNox8的表达，但抑制OsFRO1的表达。干旱胁迫显著上调OsNox1 - 3、OsNox5、OsNox9和OsFRO1的表达，但下调OsNox6的表达。高温上调OsNox5 - 9，但显著下调OsNox1 - 3和OsFRO1的表达。NaCl处理增加了OsNox2、OsNox8、OsFRO1和OsFRO7的表达，但降低了OsNox1、OsNox3、OsNox5和OsNox6的表达。这些结果表明，水稻Nox基因的表达谱具有独特的胁迫响应特征，反映了它们在应对不同环境胁迫时相关但不同的功能。
