title: Molecular cloning, characterization and expression of cathepsin D from grass carp (Ctenopharyngodon idella).
abstract: Cathepsin D is a lysosomal aspartic proteinase which participates in various degradation functions within the cell. In this current study, we cloned and characterized the complete cDNA of grass carp cathepsin D through 5'- and 3'-RACE. The cathepsin D contained a 56 bp 5' terminal untranslated region (5'-UTR), a 1197 bp open reading frame encoding 398 amino acids, and a 394 bp 3'-UTR. Grass carp cathepsin D shared high similarity with those from other species, and showed the highest amino acid identity of 91% to Danio rerio. Unlike many other organisms, the grass carp cathepsin D contains only one N-glycosylation site closest to the N-terminal. Real-time quantitative RT-PCR demonstrated that Cathepsin D expressed in all twelve tissues (bladder, brain, liver, heart, gill, muscle, fin, eye, intestines, spleen, gonad and head kidney). The relative expression levels of Cathepsin D in gonad and liver were 26.58 and 24.95 times as much as those in fin, respectively. The expression level of Cathepsin D in muscle approximately 16-fold higher, in intestines and spleen were 12-fold higher. The cathepsin D expression showed an upward trend during embryonic development. After challenged with Aeromonas hydrophil, the expression of grass carp cathepsin D gene showed significant changes in the four test tissues (liver, head kidney, spleen and intestines). The fact that the bacterial infection can obviously improve the cathepsin D expression in immune-related organs, may suggest that cathepsin D plays an important role in the innate immune response of grass carp.
authors.affiliation: College of Animal Science and Technology, Shandong Agricultural University, Taian 271018, China.
authors.forename: Zhong-dian
authors.initials: ZD
authors.lastname: Dong
authors.forename: Jiao
authors.initials: J
authors.lastname: Zhang
authors.forename: Xiang-shan
authors.initials: XS
authors.lastname: Ji
authors.forename: Fen-na
authors.initials: FN
authors.lastname: Zhou
authors.forename: Yong
authors.initials: Y
authors.lastname: Fu
authors.forename: Weiyun
authors.initials: W
authors.lastname: Chen
authors.forename: Yong-qing
authors.initials: YQ
authors.lastname: Zeng
authors.forename: Tong-ming
authors.initials: TM
authors.lastname: Li
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
mesh_terms: D016980:Aeromonas hydrophila / Q000276:immunology; D000818:Animals; D001483:Base Sequence; D002347:Carps; D002402:Cathepsin D / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D016000:Cluster Analysis; D019295:Computational Biology; D017931:DNA Primers / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D005393:Fish Diseases / Q000196:embryology / Q000276:immunology* / Q000382:microbiology*; D040461:Gene Components; D020869:Gene Expression Profiling / Q000662:veterinary; D018507:Gene Expression Regulation, Developmental / Q000276:immunology*; D016905:Gram-Negative Bacterial Infections / Q000276:immunology / Q000662:veterinary*; D008969:Molecular Sequence Data; D010802:Phylogeny; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D017422:Sequence Analysis, DNA / Q000662:veterinary; D017385:Sequence Homology; D013045:Species Specificity
chemical_list: D017931:DNA Primers; D018076:DNA, Complementary; D002402:Cathepsin D