title: Localization of rRNA synthesis in Bacillus subtilis: characterization of loci involved in transcription focus formation.
abstract: In Bacillus subtilis, RNA polymerase becomes concentrated into regions of the nucleoid called transcription foci. With green fluorescent protein-tagged RNA polymerase, these structures are only observed at higher growth rates and have been shown to represent the sites of rRNA synthesis. There are 10 rRNA (rrn) operons distributed around nearly half of the chromosome. In this study we analyzed the rrn composition of transcription foci with fluorescently tagged loci and showed that they comprise the origin-proximal operon rrnO but not the more dispersed rrnE or rrnD. This suggests that transcription foci comprise only the seven origin-proximal operons rrnO, rrnA, rrnJ, rrnW, rrnI, rrnH, and rrnG. These results have important implications for our understanding of microbial chromosome structure.
authors.affiliation: School of Environmental and Life Sciences, Biological Sciences, University of Newcastle, Callaghan, New South Wales 2308, Australia.
authors.forename: Karen M
authors.initials: KM
authors.lastname: Davies
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Lewis
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002876:Chromosomes, Bacterial / Q000737:chemistry / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000378:metabolism; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D051738:Origin Recognition Complex; D011401:Promoter Regions, Genetic; D012335:RNA, Ribosomal / Q000096:biosynthesis* / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D018741:Replication Origin; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism; D012407:rRNA Operon
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D008164:Luminescent Proteins; C114650:OriC chromosomal replication origin; D051738:Origin Recognition Complex; D012335:RNA, Ribosomal; D011994:Recombinant Proteins; D014764:Viral Proteins; C030069:spore-specific proteins, Bacillus; D049452:Green Fluorescent Proteins; D012321:DNA-Directed RNA Polymerases