title: Molecular characterization of MHC class I and beta-2 microglobulin in a clonal strain of ginbuna crucian carp, Carassius auratus langsdorfii.
abstract: Clonal ginbuna crucian carp is, a naturally gynogenetic fish, and is a useful model animal for studying T-cell-mediated immunity. To gain molecular information on MHC class I molecules from this species, we have identified four types of MHC class I (caauUA-S3n, caauUF-S3n, caauZE-S3n, and caauZB-S3n) and five beta 2-microglobulin (β(2)m) (caauβ2m-1a, caauβ2m-1b, caauβ2m-2, caauβ2m-3a and caauβ2m-3b) by an expressed sequence tag (EST) analysis and using homology cloning with degenerated primers. Like UA class I genes in other cyprinid fish, the caauUA-S3n shows features of classical MHC class I, such as conservation of all key amino acids interacting with antigenic peptides, and ubiquitous tissue expression. A phylogenetic analysis shows that the β(2)m-1 and β(2)m-2 isoforms are clustered with those of other cyprinid fishes, while β(2)m-3 isoforms make a cluster that is separated from a common ancestor of salmonid and cyprinid fishes. This finding suggests that the β(2)m isoforms of ginbuna cruician carp comprise two lineages and may possess different functions. The MHC class I and β(2)m sequences from one clonal strain will facilitate our understanding of the interaction of MHC class I with β(2)m in teleosts.
authors.affiliation: Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Hakozaki, Fukuoka, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Urabe
authors.forename: Tomonori
authors.initials: T
authors.lastname: Somamoto
authors.forename: Shiro
authors.initials: S
authors.lastname: Sameshima
authors.forename: Yoko
authors.initials: Y
authors.lastname: Unoki-Kato
authors.forename: Teruyuki
authors.initials: T
authors.lastname: Nakanishi
authors.forename: Miki
authors.initials: M
authors.lastname: Nakao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D005786:Gene Expression Regulation; D005805:Genes, MHC Class I / Q000235:genetics*; D006054:Goldfish / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D001613:beta 2-Microglobulin / Q000235:genetics / Q000378:metabolism*
chemical_list: D001613:beta 2-Microglobulin