Enzymatic characterization and functional analysis of EcChi3C from ridgetail white prawn Exopalaemon carinicauda

Abstract Chitinase belongs to the glycosyl hydrolases family 18 and plays key role in the development and pathogen resistance of crustaceans. In this study, the enzymatic characterization of chitinase 3C (EcChi3C) of Exopalaemon carinicauda was analyzed. In addition, we analyzed the expression profiles of EcChi3C at different tissues and different molting stages. In the all tested tissues, it was predominantly expressed in hepatopancreas, and then stomach, but poor in other tissues. In all tested molting periods, it was mainly expressed in intermolt and molting stages, but poor in other stages. The results of molting, mortality and the uropod ultrastructure of prawns after being injected with EcChi3C dsRNA were in accordance with those of the control group. In addition, there is no difference for endopodite morphology between the survival and dead individuals in experimental group. After being challenged with bacteria, the expression of EcChi3C was up-regulated significantly at 12 h and followed with a comeback at 96 h. These results suggest that EcChi3C is an important immune related gene but not a necessary gene in the molting process of E. carinicauda .