Yu Yongmei, Liu Dilin, Wang Feng, Kong Le, Lin Yanhui, Chen Leiqing, Jiang Wenjing, Hou Xueru, Xiao Yanxia, Fu Gongzhen, Liu Wuge, Huo Xing
College of Agriculture, South China Agricultural University, Guangzhou 510642, China.
Rice Research Institute, Guangdong Academy of Agricultural Sciences/South China High-Quality Rice Breeding Laboratory (Jointly Established by Ministry of Agriculture and Rural Affairs and Provincial Government)/Guangdong Key Laboratory of Rice Science and Technology/Guangdong Rice Engineering Laboratory, Guangzhou 510640, China.
Int J Mol Sci. 2024 Dec 13;25(24):13380. doi: 10.3390/ijms252413380.
Rice is a short-day thermophilic crop that originated from the low latitudes of the tropics and subtropics; it requires high temperatures for growth but is sensitive to low temperatures. Therefore, it is highly important to explore and analyze the molecular mechanism of cold tolerance in rice to expand rice planting areas. Here, we report a phenotypic evaluation based on low-temperature stress in indica rice (R998) and wild rice (GZW) and a comparative transcriptomic study conducted at six time points. After 7 days of low-temperature treatment at 10 °C, R998 exhibited obvious yellowing and greening of the leaves, while GZW exhibited high low-temperature resistance, and the leaves maintained their normal morphology and exhibited no yellowing; GZW has a higher survival rate. Principal component analysis (PCA) and cluster analysis of the RNA-seq data revealed that the difference in low-temperature resistance between the two cultivars was caused mainly by the difference in low-temperature treatment after 6 h. Differential expression analysis revealed 2615 unique differentially expressed genes (DEGs) in the R998 material, 1578 unique DEGs in the GZW material, 1874 unique DEGs between R998 and GZW, and 2699 DEGs that were differentially expressed not only between cultivars but also at different time points in the same material under low-temperature treatment. A total of 15,712 DEGs were detected and were significantly enriched in the phenylalanine metabolism, photosynthesis, plant hormone signal transduction, and starch and sucrose metabolism pathways. These 15,712 DEGs included 1937 genes encoding transcription factors (TFs), of which 10 have been identified with functional validation in previous studies. In addition, a gene regulatory network was constructed via weighted gene correlation network analysis (WGCNA), and 12 key genes related to low-temperature tolerance in rice were identified, including five genes encoding TFs, one of which was identified and verified in previous studies. These results provide a theoretical basis for an in-depth understanding of the molecular mechanism of low-temperature tolerance in rice and provide new genetic resources for the study of low-temperature tolerance in rice.
水稻是一种起源于热带和亚热带低纬度地区的短日照喜温作物；其生长需要高温，但对低温敏感。因此，探索和分析水稻耐冷性的分子机制对于扩大水稻种植面积至关重要。在此，我们报告了基于籼稻（R998）和野生稻（GZW）低温胁迫的表型评价以及在六个时间点进行的比较转录组学研究。在10℃低温处理7天后，R998叶片出现明显的黄化和返绿现象，而GZW表现出较高的耐低温性，叶片保持正常形态且未出现黄化；GZW的存活率更高。对RNA测序数据进行主成分分析（PCA）和聚类分析表明，两个品种耐低温性的差异主要是由6小时后低温处理的差异引起的。差异表达分析显示，R998材料中有2615个独特的差异表达基因（DEG），GZW材料中有1578个独特的DEG，R998和GZW之间有1874个独特的DEG，还有2699个DEG不仅在品种间差异表达，而且在同一材料低温处理的不同时间点也差异表达。共检测到15712个DEG，它们在苯丙氨酸代谢、光合作用、植物激素信号转导以及淀粉和蔗糖代谢途径中显著富集。这15712个DEG包括1937个编码转录因子（TF）的基因，其中10个在先前的研究中已通过功能验证。此外，通过加权基因共表达网络分析（WGCNA）构建了基因调控网络，鉴定出12个与水稻耐低温性相关的关键基因，其中包括5个编码TF的基因，其中1个在先前的研究中已被鉴定和验证。这些结果为深入了解水稻耐低温性的分子机制提供了理论依据，并为水稻耐低温性研究提供了新的遗传资源。
