The Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
University of the Chinese Academy of Sciences, Beijing, 100049, China.
Theor Appl Genet. 2023 Jan;136(1):19. doi: 10.1007/s00122-023-04261-w. Epub 2023 Jan 21.
Chilling-tolerant QTL gene COG2 encoded an extensin and repressed chilling tolerance by affecting the compositions of cell wall. Rice as a major crop is susceptible to chilling stress. Chilling tolerance is a complex trait controlled by multiple quantitative trait loci (QTLs). Here, we identify a QTL gene, COG2, that negatively regulates cold tolerance at seedling stage in rice. COG2 overexpression transgenic plants are sensitive to cold, whereas knockout transgenic lines enhance chilling tolerance. Natural variation analysis shows that Hap1 is a specific haplotype in japonica/Geng rice and correlates with chilling tolerance. The SNP1 in COG2 promoter is a specific divergency and leads to the difference in the expression level of COG2 between japonica/Geng and indica/Xian cultivars. COG2 encodes a cell wall-localized extensin and affects the compositions of cell wall, including pectin and cellulose, to defense the chilling stress. The results extend the understanding of the adaptation to the environment and provide an editing target for molecular design breeding of cold tolerance in rice.
耐寒 QTL 基因 COG2 编码一个伸展蛋白，通过影响细胞壁的组成来抑制冷胁迫耐性。水稻作为主要作物，易受冷胁迫影响。冷胁迫耐性是由多个数量性状位点（QTLs）控制的复杂性状。在这里，我们鉴定了一个 QTL 基因 COG2，它负调控水稻幼苗期的耐冷性。COG2 过表达转基因植株对冷敏感，而敲除转基因系增强了冷胁迫耐性。自然变异分析表明，Hap1 是粳稻/籼稻中的一个特定单倍型，与冷胁迫耐性相关。COG2 启动子中的 SNP1 是一个特定的分歧，导致粳稻/籼稻和籼稻/粳稻品种之间 COG2 的表达水平存在差异。COG2 编码一个定位于细胞壁的伸展蛋白，影响细胞壁的组成，包括果胶和纤维素，以抵御冷胁迫。这些结果扩展了对环境适应的认识，并为水稻耐冷性的分子设计育种提供了编辑靶标。
