title: The Escherichia coli SMC complex, MukBEF, shapes nucleoid organization independently of DNA replication.
abstract: SMC (structural maintenance of chromosomes) complexes function ubiquitously in organizing and maintaining chromosomes. Functional fluorescent derivatives of the Escherichia coli SMC complex, MukBEF, form foci that associate with the replication origin region (ori). MukBEF impairment results in mispositioning of ori and other loci in steady-state cells. These observations led to an earlier proposal that MukBEF positions new replicated sister oris. We show here that MukBEF generates and maintains the cellular positioning of chromosome loci independently of DNA replication. Rapid impairment of MukBEF function by depleting a Muk component in the absence of DNA replication leads to loss of MukBEF foci as well as mispositioning of ori and other loci, while rapid Muk synthesis leads to rapid MukBEF focus formation but slow restoration of normal chromosomal locus positioning.
authors: Department of Biochemistry, University of Oxford, Oxford, United Kingdom.
authors: Anjana
authors: A
authors: Badrinarayanan
authors: Christian
authors: C
authors: Lesterlin
authors: Rodrigo
authors: R
authors: Reyes-Lamothe
authors: David
authors: D
authors: Sherratt
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone / Q000096:biosynthesis / Q000378:metabolism*; D020090:Chromosome Segregation; D002876:Chromosomes, Bacterial / Q000378:metabolism*; D004261:DNA Replication; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000096:biosynthesis / Q000378:metabolism*; D018741:Replication Origin; D012097:Repressor Proteins / Q000096:biosynthesis / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D029968:Escherichia coli Proteins; C067035:MukB protein, E coli; D012097:Repressor Proteins; C118650:SMC protein, Bacteria; C087115:mukE protein, E coli; C087116:mukF protein, E coli