Molecular Characterization and Expression Profiling of Three Splice Isoforms in the Redclaw Crayfish,

Sex determination/sex differentiation is determined by genetics, environmental factors, or the interactions of the two. The () gene plays an important role in the sex determination cascade signal pathway in insects. In this study, the gene was isolated and characterized from the cDNA library of gonad tissues in the redclaw crayfish, Three splice variants were identified, designated as , and , and sequence analysis showed that they had a highly conserved RRM domain. Phylogenetic analysis was performed by the NJ method, and the results revealed that the Tra-2 protein of the redclaw crayfish was very closely related to those of , , and Real-time PCR analysis showed that the three isoforms were predominantly expressed in the ovary and gradually increased with embryonic development. Additionally, the expression pattern of at different developmental stages was analyzed by qPCR and revealed that the phase of having a body length of 3 cm may be the key period for the sex differentiation of RNAi-targeting gene silencing further confirmed the function of in sexual differentiation in redclaw crayfish. Our experimental data will contribute to understanding the mechanism of sex determination in crustaceans.