Characterization of an Iron-responsive Promoter in the Protozoan Pathogen Trichomonas vaginalis

• Published in: The Journal of biological chemistry 2002-02, Vol.277 (7), p.5153-5162
• Main Authors: Tsai, Chu-Dang, Liu, Hsing-Wei, Tai, Jung-Hsiang
• Format: Article
• Language: English
• Subjects: Animals; ap65-1 gene; Base Sequence; Cell Adhesion Molecules; Cell Nucleus - metabolism; Cloning, Molecular; DNA - metabolism; Gene Deletion; Gene Expression Regulation; Iron - metabolism; Luciferases - metabolism; Molecular Sequence Data; Mutagenesis; Mutation; Plasmids - metabolism; Promoter Regions, Genetic; Protein Binding; Protozoan Proteins - genetics; Sequence Homology, Nucleic Acid; Transcription, Genetic; Transfection; Trichomonas vaginalis; Trichomonas vaginalis - genetics; Trichomonas vaginalis - metabolism
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.M110234200

Iron has been shown to regulate transcription in the protozoan pathogen Trichomonas vaginalis . In this study, a DNA transfection system was developed to monitor ap65-1 promoter activity in response to changing iron supply. In conjunction with electrophoretic mobility shift assay, iron-induced transcription of the ap65-1 gene was shown to be regulated by multiple closely spaced DNA elements spanning an iron-responsive region (−110/−54), including an iron-responsive DNA element ( −98 AGATAACGA −90 ), which overlaps with a 3′-MYB-like protein binding sequence ( −95 TAACGATAT −87 ), and three nearby T-rich sequences ( −110 ATTTTT −105 , −78 ATTATT −73 , and −59 ATTTTT −54 ). 5′- and 3′-flanking sequences of the iron-responsive region were shown to regulate basal transcription. A distal DNA regulatory region was shown to enhance both basal and iron-induced transcription. These findings delineate the DNA regulatory elements and nuclear proteins involving in iron-induced transcription of the ap65-1 gene, which provide useful tools for the future study of transcriptional regulation in T. vaginalis .