title: Actin homolog MreB and RNA polymerase interact and are both required for chromosome segregation in Escherichia coli.
abstract: The actin-like MreB cytoskeletal protein and RNA polymerase (RNAP) have both been suggested to provide the force for chromosome segregation. Here, we identify MreB and RNAP as in vivo interaction partners. The interaction was confirmed using in vitro purified components. We also present convincing evidence that MreB and RNAP are both required for chromosome segregation in Escherichia coli. MreB is required for origin and bulk DNA segregation, whereas RNAP is required for bulk DNA, terminus, and possibly also for origin segregation. Furthermore, flow cytometric analyses show that MreB depletion and inactivation of RNAP confer virtually identical and highly unusual chromosome segregation defects. Thus, our results raise the possibility that the MreB-RNAP interaction is functionally important for chromosome segregation.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, DK-5230 Odense M, Denmark.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kruse
authors.forename: Blagoy
authors.initials: B
authors.lastname: Blagoev
authors.forename: Anders
authors.initials: A
authors.lastname: Løbner-Olesen
authors.forename: Masaaki
authors.initials: M
authors.lastname: Wachi
authors.forename: Kumi
authors.initials: K
authors.lastname: Sasaki
authors.forename: Noritaka
authors.initials: N
authors.lastname: Iwai
authors.forename: Matthias
authors.initials: M
authors.lastname: Mann
authors.forename: Kenn
authors.initials: K
authors.lastname: Gerdes
mesh_terms: D000199:Actins / Q000235:genetics; D020090:Chromosome Segregation; D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D018741:Replication Origin
chemical_list: D000199:Actins; D029968:Escherichia coli Proteins; C078473:MreB protein, E coli; D012321:DNA-Directed RNA Polymerases