title: A PROP1-binding factor, AES cloned by yeast two-hybrid assay represses PROP1-induced Pit-1 gene expression.
abstract: PROP1 mutation causes combined pituitary hormone deficiency (CPHD). Several mutations are located in a transactivation domain (TAD) of Prop1, and the loss of TAD binding to cofactors is likely the cause of CPHD. PROP1 cofactors have not yet been identified. In the present study, we aimed to identify the PROP1-interacting proteins from the human brain cDNA library. Using a yeast two-hybrid assay, we cloned nine candidate proteins that may bind to PROP1. Of those nine candidates, amino-terminal enhancer of split (AES) was the most abundant, and we analyzed the AES function. AES dose-dependently decreased the PROP1-induced Pit-1 reporter gene expression. An immunoprecipitation assay revealed the relationship between AES and PROP1. In a mammalian two-hybrid assay, a leucine zipper-like motif of the AES Q domain was identified as a region that interacted with TAD. These results indicated that AES was a corepressor of PROP1.
authors.affiliation: Department of Biophysics, Kobe University Graduate School of Health Science, 7-10-2, Tomogaoka, Suma-ku, Kobe 654-0142, Japan.
authors.forename: Yuka
authors.initials: Y
authors.lastname: Sugiyama
authors.forename: Nobuko
authors.initials: N
authors.lastname: Ikeshita
authors.forename: Hiromi
authors.initials: H
authors.lastname: Shibahara
authors.forename: Daisuke
authors.initials: D
authors.lastname: Yamamoto
authors.forename: Mayuko
authors.initials: M
authors.lastname: Kawagishi
authors.forename: Genzo
authors.initials: G
authors.lastname: Iguchi
authors.forename: Keiji
authors.initials: K
authors.lastname: Iida
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Hidesuke
authors.initials: H
authors.lastname: Kaji
authors.forename: Kazuo
authors.initials: K
authors.lastname: Chihara
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Okimura
mesh_terms: D001665:Binding Sites; D001921:Brain / Q000378:metabolism; D045744:Cell Line, Tumor; D056970:Co-Repressor Proteins; D005786:Gene Expression Regulation; D015723:Gene Library; D017930:Genes, Reporter; D018398:Homeodomain Proteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D007018:Hypopituitarism / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D009154:Mutation; D010902:Pituitary Gland / Q000166:cytology / Q000378:metabolism*; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism; D050817:Transcription Factor Pit-1 / Q000235:genetics* / Q000378:metabolism; D020798:Two-Hybrid System Techniques
chemical_list: D056970:Co-Repressor Proteins; D018398:Homeodomain Proteins; C102134:Prophet of Pit-1 protein; D011994:Recombinant Proteins; D012097:Repressor Proteins; C498445:TLE5 protein, human; D050817:Transcription Factor Pit-1
keywords: AES; CPHD; GH; GH-releasing hormone; GHRH; PROP1; Pit-1; TLE1; Two-hybrid assay; amino-terminal enhancer of split; combined pituitary hormone deficiency; growth hormone; transducin-like enhancer of split-1