title: Mammalian X chromosome inactivation: testing the hypothesis of transcriptional control.
abstract: Mammalian X chromosome inactivation is generally considered to be a good example of stable transcriptional repression; however, there has been no satisfactory evidence for transcriptional control. We have made a test of the hypothesis of transcriptional control by Northern blot analysis of RNA from a woman heterozygous for a mutant Hpt allele which shows no detectable transcription of wild-type mRNA. Cells from this Hpt+ Hpt- woman were separated into HPRT+ and HPRT- subpopulations by selection in HAT or thioguanine. The HPRT+ population (in which the Hpt+ is on the active X) transcribed normal Hpt mRNA, while the HPRT- population (in which the Hpt+ allele is on the inactive X) did not. These results provide strong support for the hypothesis of transcriptional control.
authors.forename: J A
authors.initials: JA
authors.lastname: Graves
authors.forename: S M
authors.initials: SM
authors.lastname: Gartler
mesh_terms: D000483:Alleles; D002460:Cell Line; D004261:DNA Replication; D004303:Dosage Compensation, Genetic; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007041:Hypoxanthine Phosphoribosyltransferase / Q000235:genetics*; D008297:Male; D012333:RNA, Messenger / Q000235:genetics; D014158:Transcription, Genetic; D014960:X Chromosome / Q000502:physiology*
chemical_list: D012333:RNA, Messenger; D007041:Hypoxanthine Phosphoribosyltransferase