title: Molecular cloning and expression analyses of mouse betaklotho, which encodes a novel Klotho family protein.
abstract: We report here the identification of mouse betaklotho (betakl), which encodes a type I membrane protein with high resemblance to Klotho (KL). Both betaKL and KL consist of two internal repeats with homology to family 1 glycosidases, while these essential glutamates for the enzymatic activities were not conserved. The identical pattern of substitution and variation in the substituted amino acids between these two proteins indicate that they likely to form a unique family within the glycosidase family 1 superfamily. During mouse embryonic development, strong betakl expression was detected in the yolk sac, gut, brown and white adipose tissues, liver and pancreas, and in the adult, predominantly in the liver and pancreas. Despite the high structural similarity between betaKL and KL, their expression profiles were considerably different and betakl expression was not induced in kl-deficient mouse mutants.
authors.affiliation: Department of Pathology and Tumor Biology, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Ito
authors.forename: S
authors.initials: S
authors.lastname: Kinoshita
authors.forename: N
authors.initials: N
authors.lastname: Shiraishi
authors.forename: S
authors.initials: S
authors.lastname: Nakagawa
authors.forename: S
authors.initials: S
authors.lastname: Sekine
authors.forename: T
authors.initials: T
authors.lastname: Fujimori
authors.forename: Y I
authors.initials: YI
authors.lastname: Nabeshima
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D005966:Glucuronidase; D017403:In Situ Hybridization; D000090265:Klotho Proteins; D008565:Membrane Proteins / Q000235:genetics*; D051379:Mice; D018345:Mice, Knockout; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution
chemical_list: D018076:DNA, Complementary; C418622:Klb protein, mouse; D008565:Membrane Proteins; D005966:Glucuronidase; D000090265:Klotho Proteins