Identification and Expression Analysis of Dsx and Its Positive Transcriptional Regulation of IAG in Black Tiger Shrimp (Penaeus monodon)

Abstract

Doublesex (Dsx) is a polymorphic transcription factor of the DMRTs family, which is involved in male sex trait development and controls sexual dimorphism at different developmental stages in arthropods. However, the transcriptional regulation of the Dsx gene is largely unknown in decapods. In this study, we reported the cDNA sequence of PmDsx in Penaeus monodon, which encodes a 257 amino acid polypeptide. It shared many similarities with Dsx homologs and has a close relationship in the phylogeny of different species. We demonstrated that the expression of the male sex differentiation gene Dsx was predominantly expressed in the P. monodon testis, and that PmDsx dsRNA injection significantly decreased the expression of the insulin-like androgenic gland hormone (IAG) and male sex-determining gene while increasing the expression of the female sex-determining gene. We also identified a 5′-flanking region of PmIAG that had two potential cis-regulatory elements (CREs) for the PmDsx transcription. Further, the dual-luciferase reporter analysis and truncated mutagenesis revealed that PmDsx overexpression significantly promoted the transcriptional activity of the PmIAG promoter via a specific CRE. These results suggest that PmDsx is engaged in male reproductive development and positively regulates the transcription of the PmIAG by specifically binding upstream of the promoter of the PmIAG. It provides a theoretical basis for exploring the sexual regulation pathway and evolutionary dynamics of Dmrt family genes in P. monodon.

Transcriptome profiling of banana shrimp (Fenneropenaeus merguiensis) ovaries and testes: Insights into FoxL2

“…The dsRNA was diluted to 0.75 μg/μL with phosphate buffer saline (PBS), and 3 μg of dsRNA per gram of shrimp was injected into the shrimp as in previous studies [ 34 , 35 ]. Female shrimp measuring 15 ± 0.5 cm in length and 26 ± 2.8 g in weight were used in this experiment.…”

Monosex Populations of the Giant Freshwater Prawn Macrobrachium rosenbergii—From a Pre-Molecular Start to the Next Generation Era

“…Knockdown of the invertebrate double-sex and mab-3 related transcription factor 2 (idmrt-2) in S. paramamosain decreased the expression of Dmrt-like and foxl-2 genes in the testis, and IAG in the AG [71]. In the black tiger shrimp, Penaeus monodon, RNAi of Dsx significantly decreased the expression of PmIAG in the testis and was suggested as a positive regulator of IAG by specific binding upstream of the IAG promoter [72]. Similarly, Dsx was suggested to regulate IAG in the shrimp Fenneropenaeus chinensis, as knockdown of FcDsx resulted in FcIAG transcript down-regulation [73].…”