title: Biochemical Characterization of Medaka (Oryzias latipes) Transglutaminases, OlTGK1 and OlTGK2, as Orthologues of Human Keratinocyte-Type Transglutaminase.
abstract: Calcium-dependent transglutaminases (TGs) are a family of enzymes that catalyze protein cross-linking and/or attachment of primary amines in a variety of organisms. Mammalian TGs are implicated in multiple biological events such as skin formation, blood coagulation, and extracellular matrix stabilization. Medaka (Oryzias latipes) has been used as a model fish to investigate the physiological functions of mammalian proteins. By analysis of the medaka genome, we found seven TGs orthologues, some of which apparently corresponded to the mammalian TG isozymes, TG1, TG2, and Factor XIII. All orthologues had preserved amino acid residues essential for enzymatic activity in their deduced primary structures. In this study, we analyzed biochemical properties of two orthologues (OlTGK1 and OlTGK2) of mammalian epithelium-specific TG (TG1) that are significantly expressed at the transcriptional level. Using purified recombinant proteins for OlTGK1 and OlTGK2, we characterized their catalytic reactions. Furthermore, immunohistochemical analyses of fish sections revealed higher expression in the pancreas (OTGK1), intervertebral disk (OlTGK2) and pharyngeal teeth (OlTGK2) as well as in the skin epidermis.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Nagoya University, Nagoya, 464-8601 Japan.
authors.forename: Ayaka
authors.initials: A
authors.lastname: Kikuta
authors.affiliation: Graduate School of Pharmaceutical Sciences, Nagoya University, Nagoya, 464-8601 Japan.
authors.forename: Eri
authors.initials: E
authors.lastname: Furukawa
authors.affiliation: Graduate School of Pharmaceutical Sciences, Nagoya University, Nagoya, 464-8601 Japan.
authors.forename: Ryota
authors.initials: R
authors.lastname: Ogawa
authors.affiliation: Graduate School of Pharmaceutical Sciences, Nagoya University, Nagoya, 464-8601 Japan.
authors.forename: Natsuki
authors.initials: N
authors.lastname: Suganuma
authors.affiliation: Graduate School of Pharmaceutical Sciences, Nagoya University, Nagoya, 464-8601 Japan.
authors.forename: Mai
authors.initials: M
authors.lastname: Saitoh
authors.affiliation: Kitasato University School of Medicine, Sagamihara, 252-0734 Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Nishimaki
authors.affiliation: Kitasato University School of Medicine, Sagamihara, 252-0734 Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Katsumura
authors.affiliation: Kitasato University School of Medicine, Sagamihara, 252-0734 Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Oota
authors.affiliation: Radioisotope Research Institute, School of Dental Medicine, Tsurumi University, Tsurumi, Yokohama, 230-8501 Japan.
authors.forename: Tadafumi
authors.initials: T
authors.lastname: Kawamoto
authors.affiliation: Graduate School of Pharmaceutical Sciences, Nagoya University, Nagoya, 464-8601 Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Tatsukawa
authors.affiliation: Bioscience and Biotechnology Center, Nagoya University, Nagoya, 464-8601 Japan.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Hashimoto
authors.affiliation: Graduate School of Pharmaceutical Sciences, Nagoya University, Nagoya, 464-8601 Japan.
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Hitomi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004817:Epidermis / Q000201:enzymology*; D029941:Fish Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008969:Molecular Sequence Data; D009990:Oryzias / Q000378:metabolism; D010802:Phylogeny; D011503:Transglutaminases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: D029941:Fish Proteins; D011503:Transglutaminases