title: Cloning, characterization and mRNA expression of interleukin-6 in blunt snout bream (Megalobrama amblycephala).
abstract: In the present study, the interleukin-6 gene (IL-6) cDNA in blunt snout bream (Megalobrama amblycephala) was identified and its expression profiles under ammonia stress and bacterial challenge were investigated. The IL-6 sequence consisted of 1045 bp, including a 696 bp ORF which translated into a 232 amino acid (AA) protein. The protein contained a putative signal peptide of 24 AA in length. IL-6 expression analysis showed that the it is differentially expressed in various tissues under normal conditions and the highest IL-6 level was observed in the intestine tissue, followed by the liver, and then in the gills. Under ammonia stress, the IL-6 mRNA level both in spleens and intestine increased significantly (P < 0.05), with the maximum levels attained at 6 h, 12 h (72, 10-fold, respectively). Thereafter, they all significantly decreased (P < 0.01) and returned to the basal value within 48 h. Whereas, in livers it slightly decreased at 3 h firstly (0.5-fold), and then significantly (P < 0.05) increased with the maximum level attained 12 h (3-fold). Further expression analysis showed that the mRNA level of IL-6 in spleens, intestine and livers of blunt snout bream all increased significantly (P < 0.05), with maximum values attained at 6 h, 3 h, 6 h (10, 6, 18-fold, respectively) after Aeromonas hydrophila (A. hydrophila) injection, and then decreased to the basal value within 24 h which suggested that IL-6 was involved in the immune response to A. hydrophila. The cloning and expression analysis of the IL-6 provide theoretical basis to further study the mechanism of anti-adverseness and expression characteristics under stress conditions in blunt snout bream.
authors.affiliation: College of Animal Science and Technology, Henan University of Scientific and Technology, Luoyang 471003, PR China. Electronic address: zhangchunnuan12@163.com.
authors.forename: Chun-Nuan
authors.initials: CN
authors.lastname: Zhang
authors.affiliation: College of Animal Science and Technology, Henan University of Scientific and Technology, Luoyang 471003, PR China.
authors.forename: Ji-Liang
authors.initials: JL
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Aquatic Nutrition and Feed Science of Jiangsu Province, College of Animal Science and Technology, Nanjing Agricultural University, No.1 Weigang Road, Nanjing 210095, PR China.
authors.forename: Wen-Bin
authors.initials: WB
authors.lastname: Liu
authors.affiliation: College of Animal Science and Technology, Henan University of Scientific and Technology, Luoyang 471003, PR China.
authors.forename: Qiu-Jue
authors.initials: QJ
authors.lastname: Wu
authors.affiliation: College of Animal Science and Technology, Henan University of Scientific and Technology, Luoyang 471003, PR China.
authors.forename: Xiao-Chan
authors.initials: XC
authors.lastname: Gao
authors.affiliation: College of Animal Science and Technology, Henan University of Scientific and Technology, Luoyang 471003, PR China.
authors.forename: Hong-Tao
authors.initials: HT
authors.lastname: Ren
mesh_terms: D016980:Aeromonas hydrophila / Q000502:physiology; D000595:Amino Acid Sequence; D000641:Ammonia / Q000633:toxicity; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D003530:Cyprinidae / Q000145:classification / Q000235:genetics*; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D005393:Fish Diseases / Q000276:immunology*; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000276:immunology*; D016905:Gram-Negative Bacterial Infections / Q000276:immunology / Q000662:veterinary*; D015850:Interleukin-6 / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment / Q000662:veterinary; D014874:Water Pollutants, Chemical / Q000633:toxicity
chemical_list: D018076:DNA, Complementary; D029941:Fish Proteins; D015850:Interleukin-6; D012333:RNA, Messenger; D014874:Water Pollutants, Chemical; D000641:Ammonia
keywords: Aeromonas hydrophila; Ammonia stress; Expression; Interleukin-6; Megalobrama amblycephala