Genome-Wide Identification and Analysis of Nilaparvata lugens microRNAs during Challenge with the Entomopathogenic Fungus Metarhizium anisopliae

Abstract

The resistance of the notorious rice pest Nilaparvata lugens to many insecticides has caused significant concerns. Our previous study demonstrated that the fungus Metarhizium anisopliae CQMa421 shows great potential for the control of this pest, but the interactions between them are still unclear. Thus, we further investigated fungal infection-related microRNAs (miRNAs) in N. lugens during M. anisopliae CQMa421 challenge using Illumina sequencing. In this study, we constructed twenty-four small RNA libraries over different time courses (i.e., 4 h, 8 h, 16 h, and 24 h). A total of 478.62 M clean reads were collected, with each sample producing more than 13.37 M reads, after the removal of low-quality reads. We identified 2324 miRNAs and their 11,076 target genes within the twenty-four libraries by bioinformatics analysis. Differentially expressed miRNAs (DEmiRNAs), including 58 (32 upregulated vs. 26 downregulated), 62 (30 upregulated vs. 32 downregulated), 126 (71 upregulated vs. 55 downregulated), and 109 (40 upregulated vs. 69 downregulated) DEmiRNAs were identified at 4 h, 8 h, 16 h, and 24 h post-infection, respectively. We further conducted Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis to predict the functions of all target genes of DEmiRNAs. These DEmiRNAs targets identified during 24 h of infection were primarily involved in energy metabolism, lysine degradation, the FoxO signaling pathway, ubiquitin-mediated proteolysis, the mRNA surveillance pathway, and the MAPK signaling pathway. Taken together, our results provide essential information for further study of the interactions between the entomopathogenic fungus M. anisopliae and N. lugens at the posttranscriptional level.

Versatile Roles of Microbes and Small RNAs in Rice and Planthopper Interactions

“…While bacterial endosymbionts affect miRNA profiles in planthoppers, entomopathogenic microbes were also found to cause specific changes in miRNA profiles. In their investigation of the impact of the entomopathogenic fungus Metarhizium anisopliae against BPH ( N. lugens ), Xie et al (2021) found that the high biocontrol potential of M. anisopliae was linked to specific changes in miRNA profiles, and target gene functions were predicted to include genes involved in energy metabolism, ubiquitin-mediated proteolysis, and mitogen-activated protein kinase signaling pathway. A previous study investigated the transcriptome of M. anisopliae- challenged insects and indicated that fungal infection caused specific changes in the expression of membrane-related genes and genes related to cellular immune response and humoral immune factors ( Zhang et al, 2015 ).…”

The Entomopathogenic Fungus Metarhizium anisopliae Affects Feeding Preference of Sogatella furcifera and Its Potential Targets’ Identification

“…Meanwhile, the energy metabolism of the host is intensive, and many antimicrobial peptides are generated to function on the pathogens [ 24 ]. Although a few studies have examined the interaction between insect hosts and pathogens under different conditions by transcriptomic profiling [ 25 , 26 , 27 ], the means by which the rice planthopper S. furcifera responds to fungal infection is less known, especially in terms of their behaviors.…”