title: Identification of the transactivating region of the homeodomain protein, hex.
abstract: The homeodomain-containing protein Hex acts as an activator as well as a repressor of transcription in animals. While its repression domain has been mapped to the amino-terminal region, the activation domain has never been identified. Here, we show that the homeodomain and the acidic carboxyl-terminal region are necessary for full activation of the sodium-dependent bile acid cotransporter gene promoter in a cell type-independent manner, suggesting that the carboxyl-terminal region comprising residues 197 to 271 functions as the activation domain. In addition, we observed that a Hex mutant without this activation domain acts as a dominant-negative mutant as to the transactivating function of Hex.
authors.affiliation: Department of Applied Molecular Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa-ku, Nagoya 464-8601.
authors.forename: Shinya
authors.initials: S
authors.lastname: Kasamatsu
authors.forename: Ayuko
authors.initials: A
authors.lastname: Sato
authors.forename: Taichi
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Vincent W
authors.initials: VW
authors.lastname: Keng
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yoshida
authors.forename: Yuka
authors.initials: Y
authors.lastname: Yamazaki
authors.forename: Masafumi
authors.initials: M
authors.lastname: Shimoda
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Miyazaki
authors.forename: Tamio
authors.initials: T
authors.lastname: Noguchi
mesh_terms: D000818:Animals; D001483:Base Sequence; D001647:Bile Acids and Salts / Q000378:metabolism; D018398:Homeodomain Proteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008156:Luciferases / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D011401:Promoter Regions, Genetic / Q000502:physiology; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012964:Sodium / Q000494:pharmacology; D014157:Transcription Factors / Q000502:physiology; D015533:Transcriptional Activation; D014407:Tumor Cells, Cultured
chemical_list: D001647:Bile Acids and Salts; D018398:Homeodomain Proteins; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D012964:Sodium; D008156:Luciferases