Functions of the transcription factor myb-like in sex determination and differentiation in Portunus trituberculatus

Abstract

The growth traits of Portunus trituberculatus show sexual dimorphism; therefore, it is important to explore and identify the functional genes related to sex determination and differentiation to establish monosexual breeding technology. Herein, the DNA sequence of myb-like, located in the sex-determining region, was obtained using comparative genomics analysis. The results of quantitative real-time reverse transcription PCR and in situ hybridization indicated that myb-like is specifically expressed in male individuals. Functional study of myb-like by eyestalk ablation and RNA interference revealed that the expression level of myb-like could significantly affect IAG (encoding insulin-like androgenic gland hormone) expression. Furthermore, using the dual-luciferase reporter system, we confirmed that the MYB-LIKE protein could regulate the expression of IAG by binding to its promoter region directly. Our findings suggest that the transcription factor myb-like gene influences sex differentiation by regulating IAG expression in P. trituberculatus. Our results could provide clues to further study the regulatory mechanism of sex determination and differentiation, and lay the theoretical foundation for exploring single-sex breeding technology.