Xiong Huaiyang, Li Yang, Yang Jing, Li Yangsheng
State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China.
Funct Plant Biol. 2012 Jun;39(6):449-461. doi: 10.1071/FP11251.
Submergence tolerance in rainfed lowland rice (Oryza sativa L.) is determined mainly by SUB1A-1, which confers the tolerance by regulating the ethylene- and gibberellin-mediated gene expression responsible for carbohydrate consumption, cell elongation and ethanolic fermentation. However, two indica rice genotypes, FR13A and Goda Heenati, both carrying this gene, exhibited differential tolerance to submergence. Comparative analysis of transcriptional profiling of the two genotypes revealed that many of antioxidant genes were more highly expressed in FR13A than in Goda Heenati under both submergence and control conditions, or only under submergence, whereas most of genes involved in biosynthesis and signalling of ethylene and GA and in anaerobic carbohydrate metabolism had comparable levels of expression between genotypes under the same conditions. H2O2 and malondialdehyde (MDA) assays demonstrated that Goda Heenati accumulated more H2O2 and had more MDA, a product of lipid peroxidation, than FR13A under submergence. These findings suggest that apart from SUB1A-mediated 'quiescence strategy', the detoxification of reactive oxygen species (ROS) is another important trait associated with submergence tolerance. The information obtained from this study helps in further understanding of the mechanism underlying submergence tolerance.
雨养低地水稻（Oryza sativa L.）的耐淹性主要由SUB1A-1决定，它通过调节乙烯和赤霉素介导的基因表达来赋予耐淹性，这些基因表达负责碳水化合物消耗、细胞伸长和乙醇发酵。然而，两种携带该基因的籼稻基因型FR13A和Goda Heenati对淹水表现出不同的耐受性。对这两种基因型转录谱的比较分析表明，在淹水和对照条件下，或仅在淹水条件下，许多抗氧化基因在FR13A中的表达水平高于Goda Heenati，而在相同条件下，参与乙烯和赤霉素生物合成及信号传导以及厌氧碳水化合物代谢的大多数基因在基因型间的表达水平相当。H2O2和丙二醛（MDA）测定表明，在淹水条件下，Goda Heenati比FR13A积累更多的H2O2，且脂质过氧化产物MDA更多。这些发现表明，除了SUB1A介导的“静止策略”外，活性氧（ROS）的解毒是与耐淹性相关的另一个重要性状。从本研究中获得的信息有助于进一步了解耐淹性的潜在机制。
