Rice Research Institute, Fujian High Quality Rice Research and Development Center, Fujian Academy of Agricultural Sciences, Fuzhou, 350019, Fujian, China.
Biomedical Science Division, College of Dental Medicine, Western University of Health Sciences, Pomona, CA, 91766, USA.
Sci Rep. 2022 Sep 1;12(1):14917. doi: 10.1038/s41598-022-19004-y.
Rice blast is a detrimental rice disease caused by the fungus Magnaporthe oryzae. Here, we identified a resistance gene from the rice cultivar Fuhui 2663 which is resistant to the rice blast isolate KJ201. Through isolated population analyses and sequencing approaches, the candidate gene was traced to chromosome 12. With the use of a map-based cloning strategy, the resistance gene was ultimately mapped to an 80-kb resistance locus region containing the Pita gene. Candidate gene prediction and cDNA sequencing indicated that the target resistance gene in Fuhui 2663 was allelic to Pita, thus being referred to as Pita-Fuhui2663 hereafter. Further analysis showed that the Fuhui 2663 protein had one amino acid change: Ala (A) residue 918 in Pita-Fuhui2663 was replaced by Ser (S) in Pita-S, leading to a significant change in the 3D structure of the Pita-S protein. CRISPR/Cas9 knockout experiments confirmed that Pita-Fuhui2663 is responsible for the resistance phenotype of Fuhui 2663. Importantly, Pita-Fuhui2663 did not affect the main agronomic traits of the variety compared to the Pita gene as verified by knockout experiments, indicative of potential applications of Pita-Fuhui2663 in broader breeding programs. Furthermore, a Pita-Fuhui2663-dCAPS molecular marker with good specificity and high efficiency was developed to facilitate rice breeding for resistance to this devastating disease.
稻瘟病是由真菌稻瘟病菌引起的一种危害性极大的水稻病害。在这里，我们从水稻品种福惠 2663 中鉴定出一个抗性基因，该基因对稻瘟病菌分离株 KJ201 具有抗性。通过分离群体分析和测序方法，候选基因被追溯到第 12 号染色体。利用基于图谱的克隆策略，最终将抗性基因定位到一个包含 Pita 基因的 80-kb 抗性基因座区域。候选基因预测和 cDNA 测序表明，福惠 2663 中的目标抗性基因与 Pita 等位，因此被称为 Pita-Fuhui2663。进一步分析表明，福惠 2663 蛋白有一个氨基酸变化：Pita-Fuhui2663 中的 Ala（A）残基 918 被 Pita-S 中的 Ser（S）取代，导致 Pita-S 蛋白的 3D 结构发生显著变化。CRISPR/Cas9 敲除实验证实，Pita-Fuhui2663 是福惠 2663 抗性表型的原因。重要的是，与 Pita 基因相比，Pita-Fuhui2663 敲除实验并未影响该品种的主要农艺性状，表明 Pita-Fuhui2663 在更广泛的育种计划中具有潜在的应用价值。此外，还开发了一个具有良好特异性和高效率的 Pita-Fuhui2663-dCAPS 分子标记，以促进对这种破坏性疾病的抗性水稻育种。
