title: Tissue-specific response of the human platelet-activating factor receptor gene to retinoic acid and thyroid hormone by alternative promoter usage.
abstract: We have studied the effects of retinoic acid (RA) and thyroid hormone (3,3',5-triiodothyronine; T3) on platelet-activating factor receptor (PAFR) gene expression in intact rats and the ability of two human PAFR gene promoters (PAFR promoters 1 and 2) to generate two transcripts (PAFR transcripts 1 and 2). Northern blotting showed that RA and T3 regulated PAFR gene expression only in rat tissues that express PAFR transcript 2. Functional analysis of the human PAFR promoter 2 revealed that responsiveness to RA and T3 was conferred through a 24-bp element [PAFR-hormone response element (HRE) located from -67 to -44 bp of the transcription start site, whereas PAFR promoter 1 did not respond to these hormones. The PAFR-HRE is composed of three direct repeated TGACCT-like hexamer motifs with 2-and 4-bp spaces, and the two upstream and two downstream motifs were identified as response elements for RA and T3. Thus, the PAF-PAFR pathway is regulated by the PAFR level altered by a tissue-specific response to RA and T3 through the PAFR-HRE of the PAFR promoter 2.
authors.affiliation: Department of Biochemistry, Faculty of Medicine, University of Tokyo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Mutoh
authors.forename: T
authors.initials: T
authors.lastname: Fukuda
authors.forename: T
authors.initials: T
authors.lastname: Kitamaoto
authors.forename: S
authors.initials: S
authors.lastname: Masushige
authors.forename: H
authors.initials: H
authors.lastname: Sasaki
authors.forename: T
authors.initials: T
authors.lastname: Shimizu
authors.forename: S
authors.initials: S
authors.lastname: Kato
mesh_terms: D000818:Animals; D001483:Base Sequence; D004268:DNA-Binding Proteins / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D008969:Molecular Sequence Data; D009206:Myocardium / Q000378:metabolism; D009928:Organ Specificity; D010980:Platelet Membrane Glycoproteins / Q000096:biosynthesis* / Q000235:genetics; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D051381:Rats; D017208:Rats, Wistar; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D018168:Receptors, Retinoic Acid / Q000378:metabolism; D011988:Receptors, Thyroid Hormone / Q000378:metabolism; D012091:Repetitive Sequences, Nucleic Acid; D012867:Skin / Q000378:metabolism; D014212:Tretinoin / Q000494:pharmacology*; D014284:Triiodothyronine / Q000494:pharmacology*; D014802:Vitamin A Deficiency / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; D010980:Platelet Membrane Glycoproteins; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D018168:Receptors, Retinoic Acid; D011988:Receptors, Thyroid Hormone; C039351:platelet activating factor receptor; D014284:Triiodothyronine; D014212:Tretinoin