AUTHOR=Peng Weiye , Song Na , Li Wei , Yan Mingxiong , Huang Chenting , Yang Yang , Duan Kangle , Dai Liangying , Wang Bing 

TITLE=Integrated Analysis of MicroRNA and Target Genes in Brachypodium distachyon Infected by Magnaporthe oryzae by Small RNA and Degradome Sequencing

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.742347

DOI=10.3389/fpls.2021.742347

ISSN=1664-462X

ABSTRACT=<p>Rice blast caused by <italic>Magnaporthe oryzae</italic> is one of the most important diseases that seriously threaten rice production. <italic>Brachypodium distachyon</italic> is a grass species closely related to grain crops, such as rice, barley, and wheat, and has become a new model plant of Gramineae. In this study, 15 small RNA samples were sequenced to examine the dynamic changes in microRNA (miRNA) expression in <italic>B. distachyon</italic> infected by <italic>M. oryzae</italic> at 0, 24, and 48 h after inoculation. We identified 432 conserved miRNAs and 288 predicted candidate miRNAs in <italic>B. distachyon</italic>. Additionally, there were 7 and 19 differentially expressed miRNAs at 24 and 48 h post-inoculation, respectively. Furthermore, using degradome sequencing, we identified 2,126 genes as targets for 308 miRNAs; using quantitative real-time PCR (qRT-PCR), we validated five miRNA/target regulatory units involved in <italic>B. distachyon–M. oryzae</italic> interactions. Moreover, using co-transformation technology, we demonstrated that <italic>BdNAC21</italic> was negatively regulated by miR164c. This study provides a new approach for identifying resistance genes in <italic>B. distachyon</italic> by mining the miRNA regulatory network of host–pathogen interactions.</p>