A novel ß-catenin from Apostichopus japonicus mediates Vibrio splendidus-induced inflammatory-like response.

ABSTRACT

ß-catenin, an adaptor molecule in Wnt/ß-catenin signaling pathway, is associated with different physiological processes such as intestinal immune, apoptosis, and inflammation-associated response. However, the function of ß-catenin is still largely unknown in Apostichopus japonicus. In the present study, we cloned and characterized ß-catenin gene from A. japonicus by RNA-seq and RACE approaches. The complete sequence of Ajß-catenin consisted of a 5' UTR of 166 bp, a 3' UTR of 501 bp and an ORF of 2433 bp encoding a protein of 810 amino acids. Ajß-catenin has a GSK-ß consensus phosphorylation site of 21 amino acids located at N-terminal region and twelve Armadillo/ß-catenin-like repeat (ARM) domains from 145 to 671 aa. Spatial expression analysis revealed that Ajß-catenin mRNA levels displayed higher abundance in intestine. For Vibrio splendidus challenged sea cucumber, Ajß-catenin transcripts reached their peak at 6 h and remained at higher levels until 24 h post infection in comparison with that of the control group. GSK-3ß inhibitor treatment could induce both Ajß-catenin and the inflammatory factors expression. Ajß-catenin silencing could also down-regulate inflammatory factors expression. These results collectively suggested that Ajß-catenin was a novel molecule mediate V. splendidus-induced immune response of A. japonicus via regulating the inflammatory factors expression.