title: Molecular characterization, 3D modelling and expression analysis of sea bass (Dicentrarchus labrax L.) interleukin-10.
abstract: Interleukin-10 (IL-10) is a pleiotropic cytokine generally known for its relevance in the resolution of inflammation, but that also has immunostimulatory properties. Here is described the isolation and characterization of the sea bass IL-10 (sbIL-10) cDNA and gene. The sbIL-10 gene encodes a 187 amino acid protein and comprises a five exon-four intron structure as other known IL-10 genes. Important structural residues are maintained in the sbIL-10 protein, including the four cysteines responsible for the two intra-chain disulfide bridges reported for human IL-10. The 3D structure of sbIL-10 was predicted. This first homology model of a fish IL-10 reveals a high degree of compatibility between the dimeric quaternary architectures of sbIL-10 and its mammalian counterparts. The phylogenetic analysis clusters sbIL-10 with other IL-10s, apart from IL-10-related molecules. The involvement of IL-10 in sea bass immune responses was demonstrated by investigating the expression profiles of IL-1beta and IL-10 in the head-kidney and spleen following intraperitoneal injection of UV-killed Photobacterium damselae ssp. piscicida. Furthermore, involvement of IL-10 in the resolution of inflammation is for the first time suggested in fish, due to the delayed maximal mRNA levels of sbIL-10 compared to those of the pro-inflammatory IL-1beta.
authors.affiliation: IBMC-Instituto de Biologia Molecular e Celular, Rua do Campo Alegre 823, 4150-180 Porto, Portugal.
authors.forename: Rute D
authors.initials: RD
authors.lastname: Pinto
authors.forename: Diana S
authors.initials: DS
authors.lastname: Nascimento
authors.forename: Marta I R
authors.initials: MI
authors.lastname: Reis
authors.forename: Ana
authors.initials: A
authors.lastname: do Vale
authors.forename: Nuno M S
authors.initials: NM
authors.lastname: Dos Santos
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001492:Bass / Q000235:genetics* / Q000276:immunology; D003001:Cloning, Molecular; D005786:Gene Expression Regulation / Q000502:physiology*; D016753:Interleukin-10 / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009928:Organ Specificity / Q000502:physiology; D017434:Protein Structure, Tertiary
chemical_list: D016753:Interleukin-10