Ring Structure of the Escherichia coli DNA-binding Protein RdgC Associated with Recombination and Replication Fork Repair

Briggs, Geoffrey S.; McEwan, Paul; Yu, Jingjing; Moore, Timothy D.; Emsley, Jonas; Lloyd, Robert G.

doi:10.1074/jbc.c700023200

Cited by 17 publications

(21 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The crystal structure of the RdgC dimer suggests dsDNA binding takes place in the central hole of the ring-shaped dimer (50). Binding of RdgC has been shown in vitro to inhibit RecA-dependent cleavage of LexA (97).…”

Section: Reca Modulating Proteinsmentioning

confidence: 99%

The SOS Regulatory Network

et al. 2008

View full text Add to dashboard Cite

All organisms possess a diverse set of genetic programs that are used to alter cellular physiology in response to environmental cues. The gram-negative bacterium, Escherichia coli, mounts what is known as the “SOS response” following DNA damage, replication fork arrest, and a myriad of other environmental stresses. For over 50 years, E. coli has served as the paradigm for our understanding of the transcriptional, and physiological changes that occur following DNA damage (400). In this chapter, we summarize the current view of the SOS response and discuss how this genetic circuit is regulated. In addition to examining the E. coli SOS response, we also include a discussion of the SOS regulatory networks in other bacteria to provide a broader perspective on how prokaryotes respond to DNA damage.

show abstract

Section: Reca Modulating Proteinsmentioning

confidence: 99%

The SOS Regulatory Network

et al. 2008

View full text Add to dashboard Cite

show abstract

“…Native RdgC gave multiple bands with the 49-bp dsDNA oligonucleotide at high protein concentrations, suggesting two or more molecules of the RdgC dimer were able to bind to each oligonucleotide. Previous studies have also described the formation of higher-order complexes (3–5), and analysis of the crystal structure suggests that a single dimer of RdgC could interact with ∼15–20 bp (21), so the higher order complexes would be consistent with a 49-bp oligonucleotide containing 2–3 binding sites. To account for the presence of multiple bands, we quantified the reduction in intensity of the band correlating to the unbound oligonucleotide rather than those associated with the formation of protein-oligonucleotide complexes.…”

Section: Resultsmentioning

confidence: 96%

“…Previous analysis of the RdgC crystal structure identified six residues as targets for mutation studies (21). Conserved residues Q212 and E218 are positioned at one end of the α6-helix, with a conserved K227 residue at the other.…”

Section: Resultsmentioning

confidence: 99%

“…Mutant RdgC proteins were expressed in YJ014, a Δ rdgC::dhfr version of BL21(DE3) pLysS, containing the relevant pT7-7 or pET22b derivative of rdgC , as described for native RdgC. Native and mutant RdgC proteins were purified using an identical protocol as described previously (21). Induced cells from 1 l of culture were resuspended in buffer A (50 mM Tris–HCl, pH 7.5, 1 mM EDTA, 1 mM DTT), lysed by sonication on ice, and cell debris was removed by centrifugation.…”

Section: Methodsmentioning

confidence: 99%

“…In order to better understand how RdgC could inhibit RecA activity, we determined the crystal structure of RdgC from E. coli (21). This structure shows RdgC to form a dimeric ring or toroid, with a head-to-head, tail-to-tail organization (Figure 1A).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The RdgC protein employs a novel mechanism involving a finger domain to bind to circular DNA

Briggs

Mahdi

et al. 2010

Nucleic Acids Research

View full text Add to dashboard Cite

The DNA-binding protein RdgC has been identified as an inhibitor of RecA-mediated homologous recombination in Escherichia coli. In Neisseria species, RdgC also has a role in virulence-associated antigenic variation. We have previously solved the crystal structure of the E. coli RdgC protein and shown it to form a toroidal dimer. In this study, we have conducted a mutational analysis of residues proposed to mediate interactions at the dimer interfaces. We demonstrate that destabilizing either interface has a serious effect on in vivo function, even though a stable complex with circular DNA was still observed. We conclude that tight binding is required for inhibition of RecA activity. We also investigated the role of the RdgC finger domain, and demonstrate that it plays a crucial role in the binding of circular DNA. Together, these data allow us to propose a model for how RdgC loads onto DNA. We discuss how RdgC might inhibit RecA-mediated strand exchange, and how RdgC might be displaced by other DNA metabolism enzymes such as polymerases and helicases.

show abstract

Proteomic characterization of a pilR regulatory mutant of Azoarcus sp. strain BH72 with the aid of gel‐based and gel‐free approaches

et al. 2010

View full text Add to dashboard Cite

The proteome of the grass endophyte Azoarcus sp. strain BH72 was analyzed by a combination of gel-based methods by means of 2-DE and MS and a gel-free approach via LC-MS/MS. Among the identified 785 proteins, synthesis of around 100 conserved hypothetical proteins could be confirmed. Membrane proteins were detected at a higher rate in the gel-free than in the gel-based approach. The abundance of proteins in the constructed proteome reference map was analyzed and the 30 most abundant proteins were determined. The reference map was then used as a starting point to characterize the regulon under control of the response regulator PilR. PilR is part of the two-component regulatory system PilSR controlling type IV pilin gene (pilAB) expression in strain BH72, which was strongly decreased (19.7-fold) in the pilR-mutant. Changes of protein composition in the wild type and the regulatory mutant were compared by the gel-based and gel-free analyses. Proteins responsible for amino acid and energy metabolism, chaperones as well as proteins that are involved in iron metabolism and iron storage were present in a pilR-mutant at different levels than in the wild-type strain. Levels of the transcriptional regulator Flp were also dependent on PilR, indicating that PilR might be part of a hierarchical regulatory cascade.

show abstract

Ring Structure of the Escherichia coli DNA-binding Protein RdgC Associated with Recombination and Replication Fork Repair

Cited by 17 publications

References 22 publications

The SOS Regulatory Network

The SOS Regulatory Network

The RdgC protein employs a novel mechanism involving a finger domain to bind to circular DNA

Proteomic characterization of a pilR regulatory mutant of Azoarcus sp. strain BH72 with the aid of gel‐based and gel‐free approaches

Contact Info

Product

Resources

About