AUTHOR=Cao Jia-Yi , Xu You-Ping , Cai Xin-Zhong 

TITLE=Integrated miRNAome and Transcriptome Analysis Reveals Argonaute 2-Mediated Defense Responses Against the Devastating Phytopathogen Sclerotinia sclerotiorum

JOURNAL=Frontiers in Plant Science

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2020.00500

DOI=10.3389/fpls.2020.00500

ISSN=1664-462X

ABSTRACT=<p>Argonaute 2 (AGO2)-mediated role in plant defense against fungal pathogens remains largely unknown. In this study, integrated miRNAome and transcriptome analysis employing <italic>ago2</italic> mutant was performed to reveal AGO2-associated miRNAs and defense responses against the devastating necrotrophic phytopathogen <italic>Sclerotinia sclerotiorum</italic>. Both miRNAome and transcriptomes of <italic>S. sclerotiorum</italic>-inoculated <italic>ago2-1</italic> mutant (<italic>ago2-Ss</italic>) and wild-type (WT<italic>-Ss</italic>) as well as mock-inoculated <italic>ago2-1</italic> mutant (<italic>ago2</italic>) and wild-type (WT) Arabidopsis plants, were analyzed by sRNA and mRNA deep sequencing. Differentially expressed genes (DEGs) and differentially expressed miRNAs (DEMs) of the comparisons WT<italic>-Ss</italic>/WT, <italic>ago2</italic>/WT, <italic>ago2-Ss</italic>/WT<italic>-Ss</italic>, and <italic>ago2-Ss</italic>/<italic>ago2</italic> were identified. Furthermore, integration analysis for the DEMs and DEGs identified over 40 potential AGO2-dependent <italic>Sclerotinia sclerotiorum</italic>-responsive (ATSR) DEM-DEG pairs involving modulation of immune recognition, calcium flux, redox homeostasis, hormone accumulation and signaling, cell wall modification and metal ion homeostasis. Data-mining result indicated that most of the DEMs were bound with AGO2. Moreover, Arabidopsis mutant analysis demonstrated that three ROS and redox homeostatasis related DEGs of identified DEM-DEG pairs, <italic>GSTU2</italic>, <italic>GSTU5</italic>, and <italic>RBOHF</italic> contributed to the AGO2-mediated defense against <italic>S. sclerotiorum</italic>. This work provides genome-wide prediction of miRNA–target gene pairs that are potentially associated with the AGO2-dependent resistance against <italic>S. sclerotiorum</italic>.</p>