Integrated small RNA and mRNA expression profiles reveals miRNAs and their target genes in response to Aspergillus flavus infection in peanut stress

Authors: ZHAO, CHUANZHI - University Of Georgia; LI, TINGTING - Shandong Academy Of Agricultural Sciences; ZHAO, YUHAN - Shandong Academy Of Agricultural Sciences; ZHAO, BAOHONG - Shandong Academy Of Agricultural Sciences; ZHAO, SHUZHEN - Shandong Academy Of Agricultural Sciences; HOU, LEI - Shandong Academy Of Agricultural Sciences; XIA, HAN - Shandong Academy Of Agricultural Sciences; Guo, Baozhu; WANG, XINGJUN - Shandong Academy Of Agricultural Sciences

Submitted to: RNA Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/20/2020
Publication Date: 5/13/2020
Citation: Zhao, C., Li, T., Zhao, Y., Zhao, B., Zhao, S., Hou, L., Xia, H., Guo, B., Wang, X. 2020. Integrated small RNA and mRNA expression profiles reveals miRNAs and their target genes in response to Aspergillus flavus infection in peanut stress. RNA Biology. 20:215. https://doi.org/10.1186/s12870-020-02426-z.
DOI: https://doi.org/10.1186/s12870-020-02426-z

Interpretive Summary: Peanut (Arachis hypogaea. L) is one of the most important oil crops in the world. Aflatoxin contamination in peanut has become one of the most serious food safety issues. Although it is a widespread problem, the underlying molecular determinants and mechanisms of peanut-A. flavus interaction have remained elusive. The goal was to study the molecular mechanism of peanut-fungus interactions, and mining peanut resistance information in order to develop resistance peanut varieties. To better understand the mechanisms, this study reported the integration analysis of resistant and susceptible peanut varieties in response to A. flavus. This study also generated a comprehensive dataset to understanding peanut response to A. flavus infection and help to elucidate miRNA-mediated molecular mechanisms in plant responses to pathogen infection.

Technical Abstract: MicroRNAs are important gene expression regulators in plants immune system. Aspergillus flavus is the most common causal agents of aflatoxin contamination in peanuts, but information for the function of miRNA in peanut-A. flavus interaction is lacking. Here, we focused on the regulatory roles of miRNAs and their targets in peanut as influenced by A. flavus. We used small RNA, transcriptome and degradome sequencing to investigate regulatory roles of miRNAs in two different peanut varieties with contrasting susceptibility to A. flavus. A total of 30 miRNAs, 447 genes and 21 potential miRNA/mRNA pairs were differentially expressed significantly as treated with A. flavus. A total of 62 miRNAs, 451 genes and 44 potential miRNA/mRNA pairs exhibited differential expression profiles between two peanut varieties. Gene Ontology (GO) analysis showed that metabolic-process related GO terms were enriched. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses further supported the GO results, in which many enriched pathways were related with biosynthesis and metabolism, such as biosynthesis of secondary metabolites and metabolic pathways. Correlation analysis of small RNA, transcriptome and degradome indicated that miR156/SPL pairs might regulate the accumulation of flavonoids in resistant and susceptible genotypes. The miR482/2118 family might regulate NBS-LRR gene which had the higher expression level in resistant genotype. These results suggested that both miR156/157/SPL and miR482/2118/NBS-LRR pairs might play crucial roles in peanut-A. flavus interaction and lead to the difference in resistance in these two varieties. This study will help to elucidate miRNA-mediated regulatory mechanisms in peanut responses to pathogen infection.