title: Expression and sub-cellular localization of human ABH family molecules.
abstract: AlkB is an Escherichia coli protein that catalyses the oxidative demethylation of 1-methyladenine and 3-methylcytosine in DNA and RNA. The enzyme activity of AlkB is dependent on a 2-oxoglutarate- and Fe(II)-dependent (2OG-Fe[II]) oxygenase domain. Human AlkB homologues (hABH), hABH1, hABH2 and hABH3, which also possess the 2OG-Fe(II) oxygenase domain, have previously been identified. Recent bioinformatics analysis suggests the existence of an additional five ABH genes in humans. In this study, we identified the hABH4-hABH7 mRNAs and determined their expression in human tissues. Moreover, an hABH2 splice variant lacking the 2OG-Fe(II) oxygenase domain and a new gene, hABH8, were cloned from testis cDNA. hABH8 possesses not only the 2OG-Fe(II) oxygenase domain but both an RNA-binding motif and a methyl-transferase domain. mRNA of the eight hABH molecules was detected in the 16 normal human tissues examined. The sub-cellular localization of EmGFP-hABH8 was restricted to the cytoplasm. EmGFP-hABH1, 3, 4, 6 and 7 were localized in both the cytoplasm and nuclei. Interestingly, the EmGFP-hABH2 splice variant localized in nucleoplasm with a dot-like pattern. In some HeLa cells transfected with EmGFP-hABH5, dot-like fluorescence was also detected in the cytoplasm. These observations provide important information for the future annotation of the hABH family of molecules.
authors.affiliation: Department of Immunology, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan. tujikawa@phs.osaka-u.ac.jp
authors.forename: Kazutake
authors.initials: K
authors.lastname: Tsujikawa
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Koike
authors.forename: Kaori
authors.initials: K
authors.lastname: Kitae
authors.forename: Aina
authors.initials: A
authors.lastname: Shinkawa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Arima
authors.forename: Takashi
authors.initials: T
authors.lastname: Suzuki
authors.forename: Mutsumi
authors.initials: M
authors.lastname: Tsuchiya
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Makino
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Furukawa
authors.forename: Noboru
authors.initials: N
authors.lastname: Konishi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamamoto
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D045643:DNA Repair Enzymes / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D018076:DNA, Complementary / Q000235:genetics; D020869:Gene Expression Profiling; D015971:Gene Expression Regulation, Enzymologic; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D015151:Immunoblotting; D008297:Male; D008969:Molecular Sequence Data; D021381:Protein Transport; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013347:Subcellular Fractions / Q000201:enzymology; D013737:Testis / Q000201:enzymology
chemical_list: D018076:DNA, Complementary; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins; D045643:DNA Repair Enzymes