Identification and characterization of a cyclophilin A gene from Chinese shrimp Fenneropenaeus chinensis: sequence features and expression profiles

Cyclophilin A (CypA), a key member of the immunophilin family, is the most abundantly expressed one among the 16 identified cyclophilins. Besides acting as an intracellular receptor for cyclosporine A, CypA plays a vital role in various pathological responses such as inflammation and microbial infections. In the present study, the full-length cDNA of Fenneropenaeus chinensis CypA (FcCypA) was cloned by RACE technique. The complete sequence of FcCypA cDNA contained a 5' untranslated region (UTR) of 33 bp, a 3' UTR of 341 bp with a polyA tail, and an open reading frame (ORF) of 495 bp encoding a polypeptide of 164 amino acids with the predicted molecular weight of 17.70 kDa. The amino acid sequence of CypA has a typical peptidyl prolyl cis-trans isomerase family tag sequence (YKGSTFHRVIPNFMCQGG) as those of other species. The mRNA transcripts of FcCypA were constitutively expressed in all the tested tissues, including eyestalk, gill, gonad, heart, hemocytes, hepatopancreas, intestine, muscle, nerve and stomach, with the highest expression level in hepatopancreas. The mRNA expression profiles of FcCypA in hemocytes and hepatopancreas could be significantly induced by the stimulation of Vibrio anguillarum suspension and white spot syndrome virus (WSSV) stock, which verifies that CypA has an effect on viral and bacterial infection in shrimps. These results indicate that CypA may be involved in the innate immunity, biological immune response and physiological stress response of Chinese shrimps.