title: Osa-miR169 Negatively Regulates Rice Immunity against the Blast FungusMagnaporthe oryzae.
abstract: miR169 is a conserved microRNA (miRNA) family involved in plant development and stress-induced responses. However, how miR169 functions in rice immunity remains unclear. Here, we show that miR169 acts as a negative regulator in rice immunity against the blast fungusMagnaporthe oryzaeby repressing the expression of nuclear factor Y-A (NF-YA) genes. The accumulation of miR169 was significantly increased in a susceptible accession but slightly fluctuated in a resistant accession uponM. oryzaeinfection. Consistently, the transgenic lines overexpressing miR169a became hyper-susceptible to differentM. oryzaestrains associated with reduced expression of defense-related genes and lack of hydrogen peroxide accumulation at the infection site. Consequently, the expression of its target genes, the NF-YA family members, was down-regulated by the overexpression of miR169a at either transcriptional or translational level. On the contrary, overexpression of a target mimicry that acts as a sponge to trap miR169a led to enhanced resistance toM. oryzae. In addition, three of miR169's target genes were also differentially up-regulated in the resistant accession uponM. oryzaeinfection. Taken together, our data indicate that miR169 negatively regulates rice immunity againstM. oryzaeby differentially repressing its target genes and provide the potential to engineer rice blast resistance via a miRNA.
authors.affiliation: Rice Research Institute and Key Lab for Major Crop Diseases, Sichuan Agricultural University at WenjiangChengdu, China; Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Sichuan Agricultural University at WenjiangChengdu, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Rice Research Institute and Key Lab for Major Crop Diseases, Sichuan Agricultural University at Wenjiang Chengdu, China.
authors.forename: Sheng-Li
authors.initials: SL
authors.lastname: Zhao
authors.affiliation: Rice Research Institute and Key Lab for Major Crop Diseases, Sichuan Agricultural University at Wenjiang Chengdu, China.
authors.forename: Jin-Lu
authors.initials: JL
authors.lastname: Li
authors.affiliation: College of Agronomy, Sichuan Agricultural University at Wenjiang Chengdu, China.
authors.forename: Xiao-Hong
authors.initials: XH
authors.lastname: Hu
authors.affiliation: Rice Research Institute and Key Lab for Major Crop Diseases, Sichuan Agricultural University at Wenjiang Chengdu, China.
authors.forename: He
authors.initials: H
authors.lastname: Wang
authors.affiliation: Rice Research Institute and Key Lab for Major Crop Diseases, Sichuan Agricultural University at Wenjiang Chengdu, China.
authors.forename: Xiao-Long
authors.initials: XL
authors.lastname: Cao
authors.affiliation: Rice Research Institute and Key Lab for Major Crop Diseases, Sichuan Agricultural University at Wenjiang Chengdu, China.
authors.forename: Yong-Ju
authors.initials: YJ
authors.lastname: Xu
authors.affiliation: Rice Research Institute and Key Lab for Major Crop Diseases, Sichuan Agricultural University at Wenjiang Chengdu, China.
authors.forename: Zhi-Xue
authors.initials: ZX
authors.lastname: Zhao
authors.affiliation: Rice Research Institute and Key Lab for Major Crop Diseases, Sichuan Agricultural University at Wenjiang Chengdu, China.
authors.forename: Zhi-Yuan
authors.initials: ZY
authors.lastname: Xiao
authors.affiliation: Rice Research Institute and Key Lab for Major Crop Diseases, Sichuan Agricultural University at Wenjiang Chengdu, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Yang
authors.affiliation: Rice Research Institute and Key Lab for Major Crop Diseases, Sichuan Agricultural University at WenjiangChengdu, China; Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Sichuan Agricultural University at WenjiangChengdu, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Fan
authors.affiliation: Rice Research Institute and Key Lab for Major Crop Diseases, Sichuan Agricultural University at WenjiangChengdu, China; College of Agronomy, Sichuan Agricultural University at WenjiangChengdu, China.
authors.forename: Fu
authors.initials: F
authors.lastname: Huang
authors.affiliation: Rice Research Institute and Key Lab for Major Crop Diseases, Sichuan Agricultural University at WenjiangChengdu, China; Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Sichuan Agricultural University at WenjiangChengdu, China.
authors.forename: Wen-Ming
authors.initials: WM
authors.lastname: Wang
keywords: miR169; microRNA; nuclear factor Y-A; rice blast; target mimicry