Characterization of MicroRNAs Associated with Reproduction in the Brown Planthopper, Nilaparvata lugens

Abstract

Insects have a robust capacity to produce offspring for propagation, and the reproductive events of female insects have been achieved at the molecular and physiological levels via regulatory gene pathways. However, the roles of MicroRNAs (miRNAs) in the reproductive development of the brown planthopper (BPH), Nilaparvata lugens, remain largely unexplored. To understand the roles of miRNAs in reproductive development, miRNAs were identified by Solexa sequencing in short-winged (SW) female adults of BPH. Small RNA libraries derived from three developmental phases (1 day, 3 days, and 5 days after emergence) were constructed and sequenced. We identified 905 miRNAs, including 263 known and 642 novel miRNAs. Among them, a total of 43 miRNAs were differentially expressed in the three developmental phases, and 14,568 putative targets for 43 differentially expressed miRNAs (DEMs) were predicted by TargetScan and miRanda. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of the predicted miRNA targets illustrated the putative roles for these DEMs in reproduction. The progress events were annotated, including oogenesis, lipid biosynthetic process, and related pathways such as apoptosis, ABC transporters, and amino acid metabolism. Four highly abundant DEMs (miR-9a-5p, miR-34-5p, miR-275-3p, and miR-317-3p) were further screened, and miR-34-5p was confirmed to be involved in the regulation of reproduction. Overexpression of miR-34-5p via injecting its mimics reduced fecundity and decreased Vg expression. Moreover, target genes prediction for miR-34-5p showed they might be involved in 20E signaling cascades, apoptosis, and gonadal development, including hormone receptor 4 (HR4), caspase-1 (Cp-1), and spermatogenesis-associated protein 20 (SPATA20). These findings provide a valuable resource for future studies on the role of miRNAs in BPH reproductive development.

Exportin 1 is required for the reproduction and maize mosaic virus accumulation in its insect vectorPeregrinus maidis

“…Pharmacological and genetic XPO1 inhibition caused vulval bursting and sterility by affecting primary-miRNA-to-pre-miRNA processing in C. elegans (Büssing et al, 2010). In N. lugens , silencing of core components of miRNA pathway drastically affected insect development and reproduction (Wang et al, 2023a). RNAi-mediated silencing of Argonaute1 , Dicer1 and Drosha caused impaired ovary and oocytes development with significant reduction of laid eggs (Wang et al, 2023a).…”

“…In N. lugens , silencing of core components of miRNA pathway drastically affected insect development and reproduction (Wang et al, 2023a). RNAi-mediated silencing of Argonaute1 , Dicer1 and Drosha caused impaired ovary and oocytes development with significant reduction of laid eggs (Wang et al, 2023a). Similarly, Dicer1 silencing negatively affected ovary development and fecundity of the white-backed planthopper, Sogatella furcifera (Zeng et al, 2023).…”

The microRNA pathway core genes are indispensable for development and reproduction in the brown planthopper, Nilaparvata lugens

“…miRNAs have attracted great attention because of their important roles in regulating multiple biological processes in insects. Injection of synthetic mimics of miR‐34‐5p resulted in low fecundity and low expression of reproduction‐related genes, for example, Vg (Wang et al, 2022). In addition, miR‐34‐5p directly regulates the target gene EcR , consequently impacting the fecundity and development of lepidopteran insects (Li et al, 2022).…”

“…The insects were reared on susceptible rice seedlings cv. Taichung Native 1 (TN1) at 27 ± 1°C, 70% relative humidity, and a 16‐h light: 8‐h dark photoperiod, as described previously (Wang et al, 2022). Compared with long‐winged morphs, short‐winged morphs often have high reproductive capabilities under sufficient nutrition conditions, so short‐winged morphs were considered in this study.…”

Cross-kingdom RNA interference mediated by insect salivary microRNAs may suppress plant immunity

“…The resulting raw data underwent quality trimming, which involved the removal of adapters and low-quality sequences, using the Cutadapt tool ( 48 ). Furthermore, N. lugens miRNAs were identified based on a previously described method ( 49 ). The mapped miRNAs were then subjected to BLAST analysis against the N. lugens ( https://www.ncbi.nlm.nih.gov/datasets/genome/GCF_014356525.2/ ) and the O. sativa ( https://data.jgi.doe.gov/search?q=Oryza+sativa&expanded=Phytozome-323 ) genomes.…”