Characterization and expression analysis of β-catenin from Exopalaemon carinicauda (Holthuis, 1950) (Caridea, Palaemonidae) in embryonic development and immune response to bacteria

β-catenin is an important signal transduction protein in the canonical Wnt/β-catenin pathway, which is widely involved in the development of animals. However, the role of β-catenin in crustaceans is still unclear. In this study, the cDNA of β-catenin from Exopalaemon carinicauda (Holthuis, 1950) was identified and characterized. The open reading frame (ORF) is 2424 bp, which encodes 807 amino acids containing an N-terminal region of a GSK-β consensus phosphorylation site and a central region of 11 armadillo (ARM) repeats. The tissue distribution showed that β-catenin was highly expressed in ovary, testis, hepatopancreas, heart, and gills. During embryonic development, the transcript of β-catenin was relatively high in the zygote, and the thirty-two-cell stage, blastula stage, gastrula stage, and nauplius stage. The transcripts of β-catenin in haemocytes, gills, and hepatopancreas were significantly up-regulated after infection with Vibrio anguillarum Bergeman, 1909. These results indicate that β-catenin participates in the regulation of embryonic development and in the immune response in E. carinicauda.