title: Molecular cloning and expression analysis of T-bet in ginbuna crucian carp (Carassius auratus langsdorfii).
abstract: In the adaptive immune system of mammals, naive helper T (Th) cells differentiate into Th1 or Th2 cells. The T-box expressed in T cells (T-bet) is a member of a family of T-box transcription factors that regulates the expression of IFN-gamma and plays a crucial role in Th1 cell differentiation and cell-mediated immunity. We cloned and sequenced T-bet cDNA for the first time from non-mammalian species, ginbuna crucian carp. Ginbuna T-bet was composed of 608 predicted amino acids and showed 41.5% identity with human T-bet (Tbx21), and human and ginbuna T-bet share 77.3% identity in their T-box regions. Comparative genomic analysis showed conserved synteny in these regions between zebrafish, fugu, medaka and human T-bet. Phylogenetic analysis indicated that ginbuna T-bet is closely related to that of mouse and human. In unstimulated fish, ginbuna T-bet mRNA was strongly expressed in peripheral blood leukocytes (PBL), head kidney (HK) and spleen. RT-PCR analysis in kidney cells sorted by FACS revealed that T-bet was strongly expressed in surface-IgM-negative lymphocytes in comparison to IgM-positive lymphocytes. These results suggest that ginbuna T-bet is involved in the immune system, especially in T-cell function, and is an important tool to analyze teleost cell-mediated immunity.
authors.affiliation: Department of Veterinary Medicine, Nihon University, Fujisawa, Kanagawa 252-8510, Japan.
authors.forename: Fumio
authors.initials: F
authors.lastname: Takizawa
authors.forename: Kyosuke
authors.initials: K
authors.lastname: Araki
authors.forename: Isao
authors.initials: I
authors.lastname: Kobayashi
authors.forename: Tadaaki
authors.initials: T
authors.lastname: Moritomo
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Ototake
authors.forename: Teruyuki
authors.initials: T
authors.lastname: Nakanishi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002875:Chromosomes / Q000235:genetics; D003001:Cloning, Molecular; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006054:Goldfish / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D026801:Synteny / Q000235:genetics; D020825:T-Box Domain Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D014018:Tissue Distribution; D000098815:T-bet Transcription Factor
chemical_list: D012333:RNA, Messenger; D020825:T-Box Domain Proteins; D000098815:T-bet Transcription Factor