title: A global view of Escherichia coli Rsd protein and its interactions.
abstract: The Escherichia coli Rsd protein forms 1 : 1 complexes with sigma(70) protein, which is the major factor in determining promoter recognition by RNA polymerase. Here we describe measurements of the levels of Rsd, RNA polymerase, sigma(70) and the alternative sigma(38) factor. Rsd levels are sufficient to sequester a significant proportion of sigma(70) and immunoaffinity pull-down experiments show that this occurs in stationary phase but not in exponentially growing cells. Rsd expression is controlled by two promoters, P1 and P2. Experiments with lac fusions show that the P2 promoter is stronger than P1, that P2 is active in all phases of growth, and that this accounts for the high levels of Rsd.
authors.affiliation: School of Biosciences, University of Birmingham, Birmingham, UK.
authors.forename: Sarah E
authors.initials: SE
authors.lastname: Piper
authors.forename: Jennie E
authors.initials: JE
authors.lastname: Mitchell
authors.forename: David J
authors.initials: DJ
authors.lastname: Lee
authors.forename: Stephen J W
authors.initials: SJ
authors.lastname: Busby
mesh_terms: D000907:Antibodies, Bacterial / Q000378:metabolism; D015153:Blotting, Western; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D025941:Protein Interaction Mapping / Q000379:methods*; D012097:Repressor Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D012808:Sigma Factor / Q000378:metabolism
chemical_list: D000907:Antibodies, Bacterial; D029968:Escherichia coli Proteins; D012097:Repressor Proteins; C112239:Rsd protein, E coli; D012808:Sigma Factor; C106402:RNA polymerase Esigma(38); C081775:RNA polymerase sigma 70; D012321:DNA-Directed RNA Polymerases