A novel chemerin receptor 1 (Chemerin1) takes part in the immune response of cobia (Rachycentron canadum)

Fish Shellfish Immunol Rep. 2022 May 21:3:100057. doi: 10.1016/j.fsirep.2022.100057. eCollection 2022 Dec.

Abstract

Chemerin receptor 1 (Chemerin1) plays a critical role in innate and adaptive immune systems. In this study, a cobia (Rachycentron canadum) Chemerin1 was identified, and its molecular characterization and expression patterns were analyzed. Multiple sequence alignment revealed that the RcChemerin1 possessed a typical dynein regulatory complex (DRC) motif. There was also a potential N-glycosylation site in the extracellular regions of the N-terminus and intracellular loops (ICL) 1 region. Phylogenetic analysis demonstrated that the RcChemerin1 was clustered together with homologous proteins from other fish species. RcChemerin1 was constitutively expressed in a wide range of tissues (especially in immune-related tissues) with different expression levels, which suggests that the RcChemerin1 plays different roles in un-stimulated tissues. RcChemerin1 expression showed up-regulation in the head kidney after Vibrio harveyi challenge. Up-regulation in the head kidney and spleen was also observed after polyinosinic-polycytidylic acid (poly I: C) challenge, which suggests that RcChemerin1 may play vital roles during bacterial and viral infection. The differential responses of immune organs to bacteria and poly I: C imply the differences in defense mechanisms against viruses and bacteria.

Keywords: Chemerin1; Rachycentron canadum; Vibrio harveyi; poly I: C.