Identification of androgenic gland microRNA and their target genes to discover sex-related microRNA in the oriental river prawn, Macrobrachium nipponense.

The oriental river prawn, Macrobrachium nipponense, is an important aquaculture species in China. The androgenic gland produces hormones that play crucial roles in the differentiation of crustaceans to the male sex. MicroRNA (miRNA) post-transcriptionally regulates many protein-coding genes, influencing important biological and metabolic processes. However, currently, there is no published data identifying miRNA in M. nipponense. In this study, we identified novel miRNA in the androgenic gland of M. nipponense. Using the high-throughput Illumina Solexa system, 1077 miRNA were identified from small RNA libraries by aligning with the de novo androgenic gland transcriptome of M. nipponense (obtained from RNA-Seq) and the sequences in the miRBase21 database. A total of 8,248, 76,011, and 78,307 target genes were predicted in the EST and SRA sequences provided in the NCBI database, and the androgenic gland transcriptome of M. nipponense, respectively. Some potential sex-related miRNA were identified based on the function of the predicted target genes. The results of our study provide new information regarding the miRNA expression in M. nipponense, which could be the basis for further genetic studies on decapod crustaceans.