title: The omega subunit of Escherichia coli K-12 RNA polymerase is not required for stringent RNA control in vivo.
abstract: Igarashi et al. (K. Igarashi, N. Fujita, and A. Ishihama, Nucleic Acids Res. 17:8755-8765, 1989) reported that the omega (omega) subunit of Escherichia coli RNA polymerase was required for stringent control as judged by in vitro transcription assays in the presence and absence of guanosine 3',5'-bispyrophosphate (ppGpp). This conclusion predicts that a deletion of the omega gene (designated rpoZ or spoS) should show a relaxed RNA control phenotype in vivo. However, we find that wild-type stringent control of stable RNA accumulation is unaffected by a spoS null allele that abolishes cellular production of the omega protein. We conclude that omega protein is not necessary for the operation of the stringent RNA control response.
authors.affiliation: Laboratory of Molecular Genetics, National Institute of Child Health and Human Development, Bethesda, Maryland 20892.
authors.forename: D
authors.initials: D
authors.lastname: Gentry
authors.forename: H
authors.initials: H
authors.lastname: Xiao
authors.forename: R
authors.initials: R
authors.lastname: Burgess
authors.forename: M
authors.initials: M
authors.lastname: Cashel
mesh_terms: D012321:DNA-Directed RNA Polymerases / Q000235:genetics*; D004926:Escherichia coli / Q000201:enzymology*; D006159:Guanosine Tetraphosphate / Q000737:chemistry; D012329:RNA, Bacterial / Q000235:genetics* / Q000378:metabolism; D012694:Serine / Q000031:analogs & derivatives / Q000737:chemistry; D014158:Transcription, Genetic
chemical_list: D012329:RNA, Bacterial; C028002:serine hydroxamate; D006159:Guanosine Tetraphosphate; D012694:Serine; D012321:DNA-Directed RNA Polymerases