title: The proteomes of transcription factories containing RNA polymerases I, II or III.
abstract: Human nuclei contain three RNA polymerases (I, II and III) that transcribe different groups of genes; the active forms of all three are difficult to isolate because they are bound to the substructure. Here we describe a purification approach for isolating active RNA polymerase complexes from mammalian cells. After isolation, we analyzed their protein content by mass spectrometry. Each complex represents part of the core of a transcription factory. For example, the RNA polymerase II complex contains subunits unique to RNA polymerase II plus various transcription factors but shares a number of ribonucleoproteins with the other polymerase complexes; it is also rich in polymerase II transcripts. We also describe a native chromosome conformation capture method to confirm that the complexes remain attached to the same pairs of DNA templates found in vivo.
authors.affiliation: Sir William Dunn School of Pathology, University of Oxford, Oxford, UK.
authors.forename: Svitlana
authors.initials: S
authors.lastname: Melnik
authors.forename: Binwei
authors.initials: B
authors.lastname: Deng
authors.forename: Argyris
authors.initials: A
authors.lastname: Papantonis
authors.forename: Sabyasachi
authors.initials: S
authors.lastname: Baboo
authors.forename: Ian M
authors.initials: IM
authors.lastname: Carr
authors.forename: Peter R
authors.initials: PR
authors.lastname: Cook
mesh_terms: D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D020543:Proteome; D012333:RNA, Messenger / Q000235:genetics; D014158:Transcription, Genetic
chemical_list: D020543:Proteome; D012333:RNA, Messenger; D012321:DNA-Directed RNA Polymerases