MicroRNA transcriptome analysis for elucidating the immune mechanism of the redclaw crayfish Cherax quadricarinatus under Decapod iridescent virus 1 infection

Abstract

Redclaw crayfish (Cherax quadricarinatus) is a large, tropical freshwater crustacean species with considerable potential of commercial production. In recent years, infection with DIV1 in redclaw crayfish is being reported in aquaculture industries, causing high mortality and huge economic losses. However, many characteristics of this virus, including pathogenesis, transmission mechanism, and host immunity, remain largely unknown.MicroRNAs are known to play important roles in numerous biological processes, and many microRNAs are reported to be involved in the regulation of immune responses. In this study, nine-small RNA libraries were constructed using hemocytes of redclaw crayfish to characterize the differentially expressed miRNAs (DE-miRNAs) at 24 and 48 h postinfection (hpi). A total of 14 and 22 DE-miRNAs were identified in response to DIV1 infection at 24 and 48 hpi, respectively. Further, functional annotation of the predicted host target genes using GO and KEGG pathway enrichment analyses indicated that relevant biological processes and signal pathways underwent miRNA-mediated regulation after DIV1 infection. Our results enhanced the understanding of the mechanisms of miRNA-mediated regulation of immune responses under DIV1 infection in crustaceans.