title: A homolog of Kunitz-type serine protease inhibitor from rock bream, Oplegnathus fasciatus: Molecular insights and transcriptional modulation in response to microbial and PAMP stimulation, and tissue injury.
abstract: Serine proteases and their inhibitors play vital roles in diverse biological processes. In this study, we identified and characterized cDNA coding for a Kunitz-type serine protease inhibitor (SPI), which we designated as RbKSPI, in a commercially important species, rock bream. The full-length cDNA sequence of RbKSPI consisted of 2452 bp with an open reading frame (ORF) of 1521 bp encoding a polypeptide of 507 amino acid (aa) residues. In the RbKSPI protein, MANEC, PKD, LDLa, and two Kunitz domains responsible for various functions were identified as characteristic features. Homology analysis revealed that RbKSPI shared the highest identity with the Kunitz homolog in Takifugu rubripes (77.6%). Phylogenetic analysis indicated that RbKSPI clusters with other teleostean KSPIs. In tissue-specific expression analysis, RbKSPI transcripts were detected in all the tested tissues, with the highest expression in gill tissue, followed by kidney and intestine. The mRNA expression of RbKSPI significantly increased in blood cells upon stimulation with two strains of bacteria (Edwardsiella tarda and Streptococcus iniae) and two pathogen-associated molecular patterns (PAMPs; LPS and poly I:C). Meanwhile, down-regulated expression of RbKSPI was observed in response to tissue injury. Collectively, these results suggest that the RbKSPI may be involved in essential immune defense against microbial pathogens and in the wound-healing process.
authors.affiliation: Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea.
authors.forename: S D N K
authors.initials: SD
authors.lastname: Bathige
authors.affiliation: Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea.
authors.forename: Navaneethaiyer
authors.initials: N
authors.lastname: Umasuthan
authors.affiliation: Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea.
authors.forename: G I
authors.initials: GI
authors.lastname: Godahewa
authors.affiliation: Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea.
authors.forename: J D H E
authors.initials: JD
authors.lastname: Jayasinghe
authors.affiliation: Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea.
authors.forename: Ilson
authors.initials: I
authors.lastname: Whang
authors.affiliation: Genetics & Breeding Research Center, National Fisheries Research & Development Institute, Geoje 656-842, Republic of Korea.
authors.forename: Jae Koo
authors.initials: JK
authors.lastname: Noh
authors.affiliation: Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea. Electronic address: jehee@jejunu.ac.kr.
authors.forename: Jehee
authors.initials: J
authors.lastname: Lee
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004266:DNA Virus Infections / Q000276:immunology / Q000662:veterinary; D020609:Edwardsiella tarda / Q000502:physiology; D004756:Enterobacteriaceae Infections / Q000276:immunology / Q000662:veterinary; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation; D007497:Iridoviridae / Q000502:physiology; D008070:Lipopolysaccharides / Q000276:immunology / Q000494:pharmacology; D008969:Molecular Sequence Data; D000069452:Pathogen-Associated Molecular Pattern Molecules / Q000494:pharmacology; D010473:Perciformes / Q000235:genetics* / Q000276:immunology*; D010802:Phylogeny; D011070:Poly I-C / Q000276:immunology / Q000494:pharmacology; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D016415:Sequence Alignment / Q000662:veterinary; D015842:Serine Proteinase Inhibitors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013290:Streptococcal Infections / Q000276:immunology / Q000662:veterinary; D013291:Streptococcus / Q000502:physiology
chemical_list: D029941:Fish Proteins; D008070:Lipopolysaccharides; D000069452:Pathogen-Associated Molecular Pattern Molecules; D015842:Serine Proteinase Inhibitors; D011070:Poly I-C
keywords: Immune challenges; Kunitz-type serine protease inhibitor (KSPI); Tissue injury; Transcriptional level