PDF(Pubmed)
Abstract：
Rice yellow mottle virus (RYMV) causes one of the most devastating rice diseases in Africa. Management of RYMV is challenging. Genetic resistance provides the most effective and environment-friendly control. The recessive resistance locus rymv2 (OsCPR5.1) had been identified in African rice (Oryza glaberrima), however, introgression into Oryza sativa ssp. japonica and indica remains challenging due to crossing barriers. Here, we evaluated whether CRISPR/Cas9 genome editing of the two rice nucleoporin paralogs OsCPR5.1 (RYMV2) and OsCPR5.2 can be used to introduce RYMV resistance into the japonica variety Kitaake. Both paralogs had been shown to complement the defects of the Arabidopsis atcpr5 mutant, indicating partial redundancy. Despite striking sequence and structural similarities between the two paralogs, only oscpr5.1 loss-of-function mutants were fully resistant, while loss-of-function oscpr5.2 mutants remained susceptible, intimating that OsCPR5.1 plays a specific role in RYMV susceptibility. Notably, edited lines with short in-frame deletions or replacements in the N-terminal domain (predicted to be unstructured) of OsCPR5.1 were hypersusceptible to RYMV. In contrast to mutations in the single Arabidopsis AtCPR5 gene, which caused severely dwarfed plants, oscpr5.1 and oscpr5.2 single and double knockout mutants showed neither substantial growth defects nor symptoms indicative lesion mimic phenotypes, possibly reflecting functional differentiation. The specific editing of OsCPR5.1, while maintaining OsCPR5.2 activity, provides a promising strategy for generating RYMV-resistance in elite Oryza sativa lines as well as for effective stacking with other RYMV resistance genes or other traits.
摘要：
水稻黄斑驳病毒（RYMV）是非洲最具破坏性的水稻疾病之一。RYMV的管理具有挑战性。遗传抗性提供了最有效和环境友好的控制。在非洲水稻（Oryzaglaberrima）中已鉴定出隐性抗性基因座rymv2（OsCPR5.1），然而,渗入水稻。由于跨越障碍，粳稻和in稻仍然具有挑战性。这里,我们评估了两个水稻核孔蛋白旁系同源物OsCPR5.1（RYMV2）和OsCPR5.2的CRISPR/Cas9基因组编辑是否可用于将RYMV抗性引入粳稻品种Kitaake。两种旁系同源物都被证明可以补充拟南芥atcpr5突变体的缺陷，表示部分冗余。尽管两个旁系同源物之间具有惊人的顺序和结构相似性，只有osppr5.1功能丧失突变体是完全抗性的，而功能丧失的osphr5.2突变体仍然易感，暗示OsCPR5.1在RYMV易感性中起特定作用。值得注意的是,在OsCPR5.1的N末端结构域（预测为非结构化）中具有短框内缺失或替换的编辑品系对RYMV高度敏感。与单个拟南芥AtCPR5基因的突变相反，导致植物严重矮化，osppr5.1和osppr5.2单和双敲除突变体既没有显示实质性的生长缺陷，也没有症状指示病变模拟表型，可能反映功能分化。OsCPR5.1的具体编辑，在保持OsCPR5.2活性的同时，提供了一种有希望的策略，用于在优良的水稻品系中产生RYMV抗性，以及与其他RYMV抗性基因或其他性状的有效堆叠。
