Osa-miR439 Negatively Regulates Rice Immunity Against Magnaporthe oryzae
Lu Junhua,
Yang Xuemei,
Chen Jinfeng,
Li Tingting,
Hu Zijin,
Xie Ying,
Li Jinlu,
Zhao Jiqun,
Pu Mei,
Feng Hui,
Fan Jing,
Huang Yanyan,
Zhang Jiwei,
Wang Wenming,
Li Yan
Affiliations
Lu Junhua
Rice Research Institute and Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu 611130, China
Yang Xuemei
Rice Research Institute and Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu 611130, China
Chen Jinfeng
Rice Research Institute and Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu 611130, China
Li Tingting
Rice Research Institute and Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu 611130, China
Hu Zijin
Rice Research Institute and Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu 611130, China
Xie Ying
Rice Research Institute and Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu 611130, China
Li Jinlu
Rice Research Institute and Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu 611130, China
Zhao Jiqun
State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China; Rice Research Institute and Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu 611130, China
Pu Mei
State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China; Rice Research Institute and Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu 611130, China
Feng Hui
State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China; Rice Research Institute and Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu 611130, China
Fan Jing
State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China; Rice Research Institute and Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu 611130, China
Huang Yanyan
State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China; Rice Research Institute and Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu 611130, China
Zhang Jiwei
State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China; Rice Research Institute and Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu 611130, China
Wang Wenming
State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China; Rice Research Institute and Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu 611130, China
Li Yan
State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China; Rice Research Institute and Key Laboratory for Major Crop Diseases, Sichuan Agricultural University, Chengdu 611130, China; Corresponding author.
Osa-miR439 is a rice-specific microRNA family. Here we showed that Osa-miR439 acted as a negative regulator in rice immunity against blast fungus Magnaporthe oryzae. Osa-miR439 differentially responded to M. oryzae between susceptible and resistant rice accessions. The accumulation of Osa-miR439 was constitutively more in the susceptible accession than in the resistant one. Transgenic lines overexpressing Osa-miR439a (OX439a) showed higher susceptibility associating with lower induction of defense-related genes and less hydrogen peroxide (H2O2) accumulation at the infection sites than the control plants. In contrast, transgenic lines expressing a target mimic of Osa-miR439 (MIM439) displayed compromised susceptibility associating with increased H2O2 accumulation. Furthermore, we found that the expression of three predicted target genes was decreased in OX439a but increased in MIM439 in comparison to control plants, and this expression was differential in susceptible and resistant accessions upon M. oryzae infection, indicating that Osa-miR439a may regulate rice blast resistance via these genes. Our results unveiled the role of Osa-miR439a in rice blast resistance and provided the potentiality to improve the blast resistance via miRNA.
