Zhang Ling-Li, Li Yan, Zheng Ya-Ping, Wang He, Yang Xuemei, Chen Jin-Feng, Zhou Shi-Xin, Wang Liang-Fang, Li Xu-Pu, Ma Xiao-Chun, Zhao Ji-Qun, Pu Mei, Feng Hui, Fan Jing, Zhang Ji-Wei, Huang Yan-Yan, Wang Wen-Ming
Rice Research Institute and Key Lab for Major Crop Diseases, Sichuan Agricultural University at Wenjiang, Chengdu, China.
State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University at Wenjiang, Chengdu, China.
Front Genet. 2020 Apr 23;11:327. doi: 10.3389/fgene.2020.00327. eCollection 2020.
MicroRNAs (miRNAs) play essential roles in the regulation of plant growth and defense responses. More and more, miRNA-3ps are reported to act in plant development and immunity. miR156 is a conserved miRNA, and most previous studies focus on its roles in plant growth, development, and yield determinacy. Here, we show that expressing a target mimic of miR156fhl-3p led to enhanced rice blast disease resistance without a yield penalty. miR156fhl-3p was differentially responsive to in susceptible and resistant accessions. Transgenic lines expressing a target mimic of miR156fhl-3p (MIM156-3p) exhibited enhanced rice blast disease resistance and increased expression of defense-related genes. MIM156-3p also enhanced the mRNA abundance of and by down-regulating miR156-5p and pre-miR156. Moreover, MIM156-3p lines displayed a decreased number of second rachis branches per panicle but enlarged grains, leading to unchanged yield per plant. Consistently, overexpressing miR156h (OX156) led to enhanced susceptibility to and decreased the expression of and . Our results indicate that miR156fhl-3p mounts a regulatory role on miR156-5p, which subsequently regulates the expression of and to improve rice blast disease resistance.
微小RNA（miRNA）在植物生长和防御反应的调控中发挥着重要作用。越来越多的研究报道miRNA-3p在植物发育和免疫中发挥作用。miR156是一种保守的miRNA，此前大多数研究聚焦于其在植物生长、发育和产量决定方面的作用。在此，我们表明，表达miR156fhl-3p的靶标模拟物可增强水稻对稻瘟病的抗性且不影响产量。miR156fhl-3p在感病和抗病材料中对（此处原文缺失相关内容）有不同反应。表达miR156fhl-3p靶标模拟物（MIM156-3p）的转基因株系表现出增强的稻瘟病抗性以及防御相关基因表达增加。MIM156-3p还通过下调miR156-5p和前体miR156增强了（此处原文缺失相关基因）的mRNA丰度。此外，MIM156-3p株系每穗二次枝梗数量减少但籽粒增大，导致单株产量不变。同样，过表达miR156h（OX156）导致对（此处原文缺失相关内容）的易感性增强，并降低了（此处原文缺失相关基因）的表达。我们的结果表明，miR156fhl-3p对miR156-5p起调控作用，进而调节（此处原文缺失相关基因）的表达以提高水稻对稻瘟病的抗性。
