title: Molecular cloning, expression analysis and functional characterization of interleukin-22 in So-iny mullet, Liza haematocheila.
abstract: In the present study, interleukin-22 (IL-22) from So-iny mullet (Liza haematocheila) was identified, and its tissue expression in both healthy and Streptococcus dysgalactiae-infected fish was examined. The full length cDNA sequence of mullet IL-22 was 1070bp, containing an open reading frame of 555bp. The deduced amino acid sequence shared high similarity (45.1-67.9%) with IL-22 from other fish species. Mullet IL-22 also contained an IL-10 family signature and four cysteine residues that were well conserved in other vertebrate IL-22 molecules. Mullet IL-22 mRNA was highly expressed in kidney, moderately expressed in liver and gut, and relatively weakly expressed in spleen, and its expression was significantly up-regulated in all the examined tissues following S. dysgalactiae infection. Furthermore, recombinant mullet IL-22 protein was shown to promote the expression of β-defensin in the four tissues and to increase the survival rate of the fish infected with S. dysgalactiae. Our results suggest mullet IL-22 plays an important role in the immune defense against bacterial infection and has the potential to be used to treat bacterial diseases in fish.
authors.affiliation: Key Laboratory of Aquaculture and Ecology of Coastal Pools of Jiangsu Province, Department of Ocean Technology, Yancheng Institute of Technology, Yancheng 224051, Jiangsu, China; School of Chemical and Biological Engineering, Yancheng Institute of Technology, Yancheng 224051, Jiangsu, China. Electronic address: qizhitao@ycit.edu.cn.
authors.forename: Zhitao
authors.initials: Z
authors.lastname: Qi
authors.affiliation: School of Chemical and Biological Engineering, Yancheng Institute of Technology, Yancheng 224051, Jiangsu, China.
authors.forename: Qihuan
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Aquaculture and Ecology of Coastal Pools of Jiangsu Province, Department of Ocean Technology, Yancheng Institute of Technology, Yancheng 224051, Jiangsu, China.
authors.forename: Zisheng
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Key Laboratory of Aquaculture and Ecology of Coastal Pools of Jiangsu Province, Department of Ocean Technology, Yancheng Institute of Technology, Yancheng 224051, Jiangsu, 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 430072, Hubei, China.
authors.forename: Shannan
authors.initials: S
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, Hubei, China. Electronic address: gaoqian@ihb.ac.cn.
authors.forename: Qian
authors.initials: Q
authors.lastname: Gao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D020869:Gene Expression Profiling; D007378:Interleukins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000494:pharmacology; D017386:Sequence Homology, Amino Acid; D023701:Smegmamorpha / Q000235:genetics*; D013290:Streptococcal Infections / Q000276:immunology; D013291:Streptococcus / Q000187:drug effects / Q000502:physiology; D016019:Survival Analysis; D023083:beta-Defensins / Q000235:genetics / Q000378:metabolism; D000097043:Interleukin-22
chemical_list: D018076:DNA, Complementary; D007378:Interleukins; D012333:RNA, Messenger; D011994:Recombinant Proteins; D023083:beta-Defensins; D000097043:Interleukin-22
keywords: Bacterial infection; Expression analysis; Interleukin-22; Liza haematocheila; Recombinant mullet IL-22; β-Defensin