Zhencong Guo

Macrobrachium rosenbergii is an important aquaculture species known as the king of freshwater prawn. Macrobrachium rosenbergii displays remarkable sexual dimorphism, yet our knowledge of the molecular mechanism underpinning sex determination and differentiation of M. rosenbergii is still fragmentary. In this study, through in silico prediction and experimental characterization, we identified a new Dmrt gene (Mr-Dsx) from M. rosenbergii. The cDNA of Mr-Dsx included a 115 bp 5′ untranslated region (UTR), a 2,568 bp open reading frame (ORF) and a 259 bp 3′ UTR. Mr-Dsx was expressed in a wide range of tissues, and showed dynamic expression changes at different moulting stages in the testis, androgenic gland (AG) and eyestalk. In response to unilateral eyestalk ablation (UEA), Mr-Dsx was significantly induced in the testis and AG. Gene knockdown of Mr-Dsx resulted in pronounced suppression of the insulin-like androgenic hormone (IAG) gene. The results suggest that Mr-Dsx is likely to be negatively regulated by the eyestalk neurohormones, and Mr-Dsx may participate in the transcriptional activation of IAG. The study characterized the potential roles of a newly identified Dmrt homologue from M. rosenbergii, and would contribute to a deeper understanding of the molecular regulatory network underlying sex differentiation and moulting of prawns.