Overexpression of the Replicative Helicase in Escherichia coli Inhibits Replication Initiation and Replication Fork Reloading

Journal of Molecular Biology
Jan-Gert BrüningPeter McGlynn

Abstract

Replicative helicases play central roles in chromosome duplication and their assembly onto DNA is regulated via initiators and helicase loader proteins. The Escherichia coli replicative helicase DnaB and the helicase loader DnaC form a DnaB6-DnaC6 complex that is required for loading DnaB onto single-stranded DNA. Overexpression of dnaC inhibits replication by promoting continual rebinding of DnaC to DnaB and consequent prevention of helicase translocation. Here we show that overexpression of dnaB also inhibits growth and chromosome duplication. This inhibition is countered by co-overexpression of wild-type DnaC but not of a DnaC mutant that cannot interact with DnaB, indicating that a reduction in DnaB6-DnaC6 concentration is responsible for the phenotypes associated with elevated DnaB concentration. Partial defects in the oriC-specific initiator DnaA and in PriA-specific initiation away from oriC during replication repair sensitise cells to dnaB overexpression. Absence of the accessory replicative helicase Rep, resulting in increased replication blockage and thus increased reinitiation away from oriC, also exacerbates DnaB-induced defects. These findings indicate that elevated levels of helicase perturb replication initiation...Continue Reading

References

Sep 1, 1987·Molecular & General Genetics : MGG·J Colasanti, D T Denhardt
Sep 1, 1995·Molecular Microbiology·K Skarstad, S Wold
Aug 30, 1996·The Journal of Biological Chemistry·K Tougu, K J Marians
Jan 15, 1997·The EMBO Journal·B MichelM Uzest
Jul 11, 1997·Journal of Molecular Biology·P McGlynnR G Lloyd
Mar 31, 1999·Proceedings of the National Academy of Sciences of the United States of America·J LiuK J Marians
Aug 24, 1999·The Journal of Biological Chemistry·J Liu, K J Marians
Sep 5, 2001·Molecular Microbiology·S J SandlerR U Johansen
Jun 18, 2002·The EMBO Journal·Megan J DaveyMike O'Donnell
Dec 18, 2002·The EMBO Journal·Brigitte W Trautinger, Robert G Lloyd
Aug 5, 2005·The Journal of Biological Chemistry·Ryan C Heller, Kenneth J Marians
Sep 29, 2005·The Journal of Biological Chemistry·Chris J CadmanPeter McGlynn
May 9, 2006·Molecular Microbiology·Ruethairat BoonsombatSteven J Sandler
Sep 27, 2006·Nucleic Acids Research·Bryony T I PaynePeter McGlynn
Apr 17, 2007·Nature Reviews. Microbiology·Melissa L Mott, James M Berger
Jun 26, 2007·Molecular Cell·Matthew LopperJames L Keck
Jul 8, 2008·Journal of Molecular Biology·Peter McGlynn, Colin P Guy
Nov 3, 2009·The Journal of Biological Chemistry·Milind K GuptaPeter McGlynn
Feb 4, 2010·Molecular Cell·Ivar IlvesMichael R Botchan
Oct 21, 2010·Nucleic Acids Research·John AtkinsonPeter McGlynn
Oct 15, 2011·Science·Joseph T P Yeeles, Kenneth J Marians
Oct 2, 2012·Cell·Ornchuma ItsathitphaisarnThomas A Steitz
Nov 20, 2012·Advances in Experimental Medicine and Biology·Peter McGlynn
Apr 9, 2013·Cell·Ernesto Arias-PalomoJames M Berger
Apr 17, 2013·Proceedings of the National Academy of Sciences of the United States of America·Milind K GuptaPeter McGlynn
May 3, 2013·Cold Spring Harbor Perspectives in Biology·Joseph T P YeelesPhilippe Pasero
May 7, 2013·Journal of Cell Science·Mona YekezareJohn F X Diffley

❮ Previous
Next ❯

Citations

Aug 27, 2016·Frontiers in Molecular Biosciences·Katarzyna E WegrzynIgor Konieczny

❮ Previous
Next ❯

Methods Mentioned

BETA
electrophoresis
flow cytometry
PCR

Related Concepts

Related Feeds

Aminoglycosides

Aminoglycoside is a medicinal and bacteriologic category of traditional Gram-negative antibacterial medications that inhibit protein synthesis and contain as a portion of the molecule an amino-modified glycoside. Discover the latest research on aminoglycoside here.

Aminoglycosides (ASM)

Aminoglycoside is a medicinal and bacteriologic category of traditional Gram-negative antibacterial medications that inhibit protein synthesis and contain as a portion of the molecule an amino-modified glycoside. Discover the latest research on aminoglycoside here.

Allergy and Asthma

Allergy and asthma are inflammatory disorders that are triggered by the activation of an allergen-specific regulatory t cell. These t cells become activated when allergens are recognized by allergen-presenting cells. Here is the latest research on allergy and asthma.