title: Cloning of interleukin-10 from African clawed frog (Xenopus tropicalis), with the Finding of IL-19/20 homologue in the IL-10 locus.
abstract: Interleukin-10 (IL-10) is a pleiotropic cytokine that plays an important role in immune system. In the present study, the IL-10 gene of African clawed frog (Xenopus tropicalis) was first cloned, and its expression pattern and 3D structure were also analyzed. The frog IL-10 mRNA encoded 172 amino acids which possessed several conserved features found in IL-10s from other species, including five-exon/four-intron genomic structure, conserved four cysteine residues, IL-10 family motif, and six α-helices. Real-time PCR showed that frog IL-10 mRNA was ubiquitous expressed in all examined tissues, highly in some immune related tissues including kidney, spleen, and intestine and lowly in heart, stomach, and liver. The frog IL-10 mRNA was upregulated at 24 h after LPS stimulation, indicating that it plays a part in the host immune response to bacterial infection. Another IL, termed as IL-20, was identified from the frog IL-10 locus, which might be the homologue of mammalian IL-19/20 according to the analysis results of the phylogenetic tree and the sequence identities.
authors.affiliation: Key Laboratory of Aquaculture and Ecology of Coastal Pool of Jiangsu Province, Department of Ocean Technology, Yancheng Institute of Technology, Yancheng, Jiangsu 224051, China ; Central Laboratory of Biology, Chemical and Biological Engineering College, Yancheng Institute of Technology, Yancheng, Jiangsu 224051, China.
authors.forename: Zhitao
authors.identifier: 0000-0002-2249-9522
authors.initials: Z
authors.lastname: Qi
authors.affiliation: Central Laboratory of Biology, Chemical and Biological Engineering College, Yancheng Institute of Technology, Yancheng, Jiangsu 224051, China.
authors.forename: Qihuan
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Aquaculture and Ecology of Coastal Pool of Jiangsu Province, Department of Ocean Technology, Yancheng Institute of Technology, Yancheng, Jiangsu 224051, China.
authors.forename: Zisheng
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Key Laboratory of Aquaculture and Ecology of Coastal Pool of Jiangsu Province, Department of Ocean Technology, Yancheng Institute of Technology, Yancheng, Jiangsu 224051, China ; Central Laboratory of Biology, Chemical and Biological Engineering College, Yancheng Institute of Technology, Yancheng, Jiangsu 224051, China.
authors.forename: Weihong
authors.initials: W
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei 430070, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Gao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D019295:Computational Biology; D015870:Gene Expression; D023061:Gene Order; D056426:Genetic Loci; D016753:Interleukin-10 / Q000737:chemistry / Q000235:genetics*; D007378:Interleukins / Q000737:chemistry / Q000235:genetics*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010802:Phylogeny; D011487:Protein Conformation; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D014981:Xenopus / Q000235:genetics*
chemical_list: D007378:Interleukins; D016753:Interleukin-10; C422042:interleukin 20