title: Characterization of the promoter region of the mouse Xist gene.
abstract: The mouse Xist gene is expressed exclusively from the inactive X chromosome and may be implicated in initiating X inactivation. To better understand the mechanisms underlying the control of Xist expression, we investigated the upstream regulatory region of the mouse Xist promoter. A 1.2-kb upstream region of the Xist gene was sequenced and promoter activity was studied by chloramphenicol acetyltransferase (CAT) assays after transfection in murine XX and XY cell lines. The region analyzed (-1157 to +917 showed no in vitro sex-specific promoter activity. However, a minimal constitutional promoter was assigned to a region from -81 to +1, and a cis element from -41 to -15 regulates promoter activity. We showed that a nuclear factor binds to an element located at -30 to -25 (TTAAAG). A second sequence at -41 to -15 does not act as an enhancer and is unable to confer transcriptional activity to the Xist gene on its own. A third region from -82 to -41 is needed for correct expression. Deletion of the segment -441 to -231 is associated with an increase in CAT activity and may represent a silencer element.
authors.affiliation: Unit of Molecular Genetics, University of Lausanne, Switzerland.
authors.forename: N
authors.initials: N
authors.lastname: Pillet
authors.forename: C
authors.initials: C
authors.lastname: Bonny
authors.forename: D F
authors.initials: DF
authors.lastname: Schorderet
mesh_terms: D016475:3T3 Cells; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D015500:Chloramphenicol O-Acetyltransferase / Q000096:biosynthesis; D002869:Chromosome Aberrations; D025063:Chromosome Disorders; D004268:DNA-Binding Proteins / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D051379:Mice / Q000235:genetics*; D008815:Mice, Inbred Strains; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated; D011994:Recombinant Proteins / Q000096:biosynthesis; D012727:Sex Characteristics; D014157:Transcription Factors / Q000235:genetics*; D014162:Transfection; D014960:X Chromosome
chemical_list: D004268:DNA-Binding Proteins; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated; D011994:Recombinant Proteins; D014157:Transcription Factors; C077885:XIST non-coding RNA; D015500:Chloramphenicol O-Acetyltransferase