Wang Chen, Song Shaowen, Fu Jun, Wang Kai, Chen Xuan, Bo Bin, Chen Zhe, Zhang Linan, Zhang Lin, Wang Xiaohui, Tang Niwen, Tian Xiangrong, Chen Liangbi, Luan Sheng, Yang Yuanzhu, Mao Dandan
Hunan Province Key Laboratory of Crop Sterile Germplasm Resource Innovation and Application, College of Life Sciences, Hunan Normal University, Changsha, China.
Key Laboratory of Southern Rice Innovation & Improvement, Ministry of Agriculture and Rural Affairs, Hunan Engineering Laboratory of Disease and Pest Resistant Rice Breeding, Yuan Longping High-Tech Agriculture Co., Ltd, Changsha, China.
Plant Biotechnol J. 2025 Mar;23(3):930-945. doi: 10.1111/pbi.14550. Epub 2024 Dec 18.
Over-application of potassium (K) fertilizer in fields has a negative impact on the environment. Developing rice varieties with high KUE will reduce fertilizer for sustainable agriculture. However, the genetic basis of KUE in a more diverse and inclusive population remains largely unexplored. Here, we show that the transcription factor OsNAC25 enhances K uptake and confers high KUE under low K supply. Disruption of OsNAC25 by CRISPR/Cas9-mediated mutagenesis led to a considerable loss of K uptake capacity in rice roots, coupled with reduced K accumulation in rice and severe plant growth defects under low- K conditions. However, the overexpression of OsNAC25 enhanced K accumulation by regulating proper K uptake capacity in rice roots. Further analysis displayed that OsNAC25 can bind to the promoter of OsSLAH3 to repress its transcription in response to low- K stress. Nucleotide diversity analyses suggested that OsNAC25 may be selected during japonica populations' adaptation of low K tolerance. Natural variation of OsNAC25 might cause differential expression in different haplotype varieties, thus conferring low K tolerance in the Hap 1 and Hap 4 -carrying varieties, and the japonica allele OsNAC25 could enhance low K tolerance in indica variety, conferring great potential to improve indica low K tolerance and grain development. Taken together, we have identified a new NAC regulator involved in rice low K tolerance and grain development, and provide a potential target gene for improving low K tolerance and grain development in rice.
田间过量施用钾肥对环境有负面影响。培育钾利用效率高的水稻品种将减少肥料用量，以实现可持续农业。然而，在一个更加多样化和包容性更强的群体中，钾利用效率的遗传基础在很大程度上仍未得到探索。在这里，我们表明转录因子OsNAC25在低钾供应条件下增强钾吸收并赋予高钾利用效率。通过CRISPR/Cas9介导的诱变破坏OsNAC25导致水稻根系钾吸收能力显著丧失，同时水稻中钾积累减少，在低钾条件下植株生长严重缺陷。然而，OsNAC25的过表达通过调节水稻根系适当的钾吸收能力增强了钾积累。进一步分析表明，OsNAC25可以结合OsSLAH3的启动子以响应低钾胁迫抑制其转录。核苷酸多样性分析表明，OsNAC25可能在粳稻群体适应低钾耐受性的过程中被选择。OsNAC25的自然变异可能导致不同单倍型品种中的差异表达，从而赋予携带单倍型1和单倍型4的品种低钾耐受性，并且粳稻等位基因OsNAC25可以增强籼稻品种的低钾耐受性，为提高籼稻低钾耐受性和籽粒发育提供了巨大潜力。综上所述，我们鉴定出一个参与水稻低钾耐受性和籽粒发育的新NAC调节因子，并为改善水稻低钾耐受性和籽粒发育提供了一个潜在的靶基因。
