title: Molecular cloning and tissue expression patterns of a small conductance calcium-activated potassium channel gene in turbot (Scophthalmus maximus L.).
abstract: Calcium-activated potassium channels on plasma membrane enable potassium influx into the cell with ensuing changes in plasma membrane potential and consequent effects on cellular metabolic functions. Recently, this potassium channel was reported to regulate the cellular responses of mammalian immune cells. We have postulated the presence of such a channel in fish immune cells and its potential role in immunoregulation in fish. Employing specific primers and RNA template, we cloned a segment of a novel gene from turbot blood sample and subsequently obtained a full cDNA sequence using RACE approaches. Bioinformatic analysis revealed structural and phylogenetic characteristics of a novel small conductance calcium-activated potassium channel gene, we called TSKCa, which exhibits homologous domains to other species particularly in the transmembrane regions. Full-length TSKCa cDNA is 1698 bp with a 1632 bp open reading frame encoding a protein of 544 amino acids. TSKCa gene is expressed in majority of the tested organs and tissues of turbot. To assess the postulated immune function of TSKCa, we infected turbot with the pathogen Vibrio anguillarum. Here, semi-quantitative RT-PCR analysis demonstrated increased mRNA expression of TSKCa in head kidney, spleen and blood, indicating an important role of TSKCa in these organ tissues that mediate the immune defense response of turbot. In contrast, there was less change in expression in the turbot intestines and liver which were less implicated in the immune response in present study.
authors.affiliation: The Key Laboratory of Marine Bioactive Substance, SOA, Qingdao 266061, PR China.
authors.forename: Bailin
authors.initials: B
authors.lastname: Cong
authors.forename: Guang
authors.initials: G
authors.lastname: Han
authors.forename: Xiao-Hang
authors.initials: XH
authors.lastname: Huang
authors.forename: Sheng-Hao
authors.initials: SH
authors.lastname: Liu
authors.forename: Chen-Lin
authors.initials: CL
authors.lastname: Liu
authors.forename: Xue-Zheng
authors.initials: XZ
authors.lastname: Lin
authors.forename: Pei-Qing
authors.initials: PQ
authors.lastname: He
authors.forename: Herbert
authors.initials: H
authors.lastname: Gasaino
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D005393:Fish Diseases / Q000276:immunology; D005412:Flatfishes / Q000235:genetics* / Q000378:metabolism*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D008969:Molecular Sequence Data; D010802:Phylogeny; D012333:RNA, Messenger / Q000378:metabolism; D016415:Sequence Alignment; D051640:Small-Conductance Calcium-Activated Potassium Channels / Q000235:genetics* / Q000378:metabolism*; D014733:Vibrio / Q000502:physiology; D014735:Vibrio Infections / Q000276:immunology
chemical_list: D012333:RNA, Messenger; D051640:Small-Conductance Calcium-Activated Potassium Channels