Cui Yanchun, Huang Lifang, Liu Peng, Wang Xiaodong, Wu Bi, Tan Yongjun, Huang Xuan, Hu Xiaojie, He Zhankun, Xia Yuqi, Li Zebang, Zhang Wenli, Tang Wenbang, Xing Yongzhong, Chen Caiyan, Mao Donghai
Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China.
University of Chinese Academy of Sciences, Beijing, China.
Nat Commun. 2025 May 2;16(1):4100. doi: 10.1038/s41467-025-59449-z.
Rice (Oryza sativa L.), a chilling-sensitive staple crop originating from tropical and subtropical Asia, can be cultivated in temperate regions through the introduction of chilling tolerance traits. However, the molecular mechanisms underlying this adaptation remain largely unknown. Herein, we show that HAN2, a quantitative trait locus, confers chilling tolerance in temperate japonica rice. HAN2 encodes an auxin efflux transporter (OsABCB5) and negatively regulates chilling tolerance, potentially via auxin-mediated signaling pathway. During rice domestication, HAN2 has undergone selective divergence between the indica and temperate japonica subspecies. In temperate japonica rice, the insertion of a Copia long terminal repeat retrotransposon downstream of HAN2 reduces its expression, thereby enhancing chilling tolerance and facilitating adaptation to temperate climates. Introgression of the temperate japonica HAN2 allele into indica rice significantly improves chilling tolerance at both seedling and booting stages. These findings advance our understanding of rice northward expansion and provide a valuable genetic resource for improving yield stability under chilling stress.
水稻（Oryza sativa L.）是一种原产于亚洲热带和亚热带地区的冷敏感主粮作物，通过引入耐冷性状可在温带地区种植。然而，这种适应性背后的分子机制在很大程度上仍不清楚。在此，我们表明数量性状基因座HAN2赋予温带粳稻耐冷性。HAN2编码一种生长素外排转运蛋白（OsABCB5），并可能通过生长素介导的信号通路负向调节耐冷性。在水稻驯化过程中，HAN2在籼稻和温带粳稻亚种之间发生了选择性分化。在温带粳稻中，HAN2下游插入一个Copia长末端重复反转录转座子会降低其表达，从而增强耐冷性并促进对温带气候的适应。将温带粳稻HAN2等位基因导入籼稻可显著提高幼苗期和孕穗期的耐冷性。这些发现推进了我们对水稻向北扩张的理解，并为提高冷胁迫下的产量稳定性提供了宝贵的遗传资源。
