Expression profiles of dnaA null, rok null, and dnaA null; rok null mutants
Ontology highlight
ABSTRACT:
ORGANISM(S): Bacillus subtilis
SUBMITTER: Alan Grossman
PROVIDER: E-GEOD-69788 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:To identify potential targets of co-regulation by DnaA and Rok, we compared the transcriptional profiles of dnaA null, rok null, and dnaA null rok null mutants. Because a dnaA null mutant requires an oriC- strain background, we used an oriC- oriN+ background for all strains, to allow direct comparisons.
2015-06-13 | GSE69788 | GEO
Project description:Assays 1-4: Effects of DnaA activity on S. meliloti chromosome, pSymA and pSymB replicon bias. Sheared DNA extracts of IPTG-induced vs uninduced cultures of DnaA (Assays 1,2) or Hda (Assays 3,4) overexpressors were labeled with Cy3 or Cy5 and hybridized applying dye-swap replicate design. Assay 5: Hybridization of sheared DNA of logarithmic (Cy3-labeled) vs stationary phase (Cy5-labeled) culture.
2015-10-04 | E-MTAB-3924 | biostudies-arrayexpress
Project description:The ubiquitous protein DnaA is a chromosomal DNA replication initiator and transcription factor. It binds to 9-bp DNA sites called "DnaA-boxes" that are localized within the replication origin (oriC) and throughout chromosomal DNA, usually in the proximity of the promoter regions. During stress, bacteria undergo metabolic shifts that halt their growth and activate survival mechanisms. One outcome of these shifts is the accumulation of long chains of polyphosphate (polyP), an evolutionarily conserved linear polymer composed of up to 1,000 phosphate groups. It was previously identified that DnaA and the Lon protease bind to polyP, which stimulates Lon for the polyP-dependent DnaA proteolysis. We assumed that it have an impact not only on DnaA intracellular concentration but might also affect DNA binding pattern. To investigate this hypothesis and to analyze the DNA interaction profile of DnaA molecules remaining in stressed cells, we performed Chromatin Immunoprecipitation coupled with DNA sequencing (ChIP-seq). To exclude the presence of nonspecifically bound proteins in the sample after immunoprecipitation using anti-DnaA antibodies, mass spectrometry analysis was performed.
2026-03-02 | PXD061973 | Pride
Project description:Expression profiles of dnaA null, rok null, and dnaA null rok null mutants
| PRJNA286854 | ENA
Project description:Double-strand breaks (DSBs) can lead to the loss of genetic information and cell death. Consequently, cells in all domains of life have evolved mechanisms to repair DSBs, including through homologous recombination. Although recombination has been well characterized, the spatial organization of this process in living cells remains poorly understood. Here, we introduced site-specific DSBs in Caulobacter crescentus, and then used time-lapse microscopy to visualize the homology search, DSB repair, and the resegregation of chromosomal DNA. Even loci tethered to opposite cell poles can efficiently release, pair to enable recombination-based repair, and then resegregate to their original locations. Resegregation occurs independent of DNA replication and without disrupting global chromosome organization. Origin-proximal regions are resegregated by the same machinery, ParABS, used to segregate undamaged chromosomes following DNA replication. In contrast, origin-distal regions efficiently resegregate after a DSB independent of ParABS, and likely without dedicated segregation proteins. Instead, we propose that a physical, spring-like force drives the resegregation of origin-distal loci after DSB repair. Caulobacter cells were depleted of DnaA for 1.5 h before synchronization. Swarmer cells were then released into DnaA depleting conditions (without IPTG) and double-strand breaks were induced for 1 h by the addition of 500 ?M vanillate. For control sample, no vanillate was added. Formadehyde (Sigma) was then added to the final concentration of 1%. Formadehyde crosslinks protein-DNA and DNA-DNA together, thereby capturing the structure of the chromosome at the time of fixation. Fixation was performed at the cell density of OD600 = 0.2. The crosslinking reactions were allowed to proceed for 30 minutes at 25 °C before quenching with 2.5 M glycine at a final concentration of 0.125 M. Fixed cells were then pelleted by centrifugation and subsequently washed twice with 1x M2 buffer (6.1 mM Na2HPO4, 3.9 mM KH2PO4, 9.3 mM NH4Cl, 0.5 mM MgSO4, 10 ?M FeSO4, 0.5 mM CaCl2) before resuspending in 1x TE buffer (10 mM Tris-HCl pH 8.0 and 1 mM EDTA) to a final concentration of 107 cells per µl. Resuspended cells were then divided into 25 µl aliquots and stored at -80 °C for no more than 2 weeks. Each Hi-C experiment was performed using two of the 25 µL aliquots. Chromosome conformation capture with next-generation seqeuncing (Hi-C) was carried out exactly as described previously (Le et al., 2013 PMID: 24158908)
2015-07-03 | E-GEOD-66811 | biostudies-arrayexpress
Project description:The ubiquitous protein DnaA is a chromosomal DNA replication initiator and transcription factor. It binds to 9-bp DNA sites called \"DnaA-boxes\" that are localized within the replication origin (oriC) and throughout chromosomal DNA, usually in the proximity of the promoter regions. During stress, bacteria undergo metabolic shifts that halt their growth and activate survival mechanisms. One outcome of these shifts is the accumulation of long chains of polyphosphate (polyP), an evolutionarily conserved linear polymer composed of up to 1,000 phosphate groups. It was previously identified that DnaA and the Lon protease bind to polyP, which stimulates Lon for the polyP-dependent DnaA proteolysis. We assumed that it have an impact not only on DnaA intracellular concentration but might also affect DNA binding pattern. To investigate this hypothesis and to analyze the DNA interaction profile of DnaA molecules remaining in stressed cells, we performed Chromatin Immunoprecipitation coupled with DNA sequencing (ChIP-seq).
2026-03-13 | E-MTAB-14964 | biostudies-arrayexpress
Project description:DNA replication is a fundamental process in biology with initiation marking its key, first step. In bacteria, DNA replication is initiated by the DnaA protein. DnaA exhibits multidomain architecture, consisting of an N-terminal domain I, linker region, AAA+ family ATPase cassette, and C-terminal DNA-binding motif. Taxon-specific regulatory functions are primarily coordinated by the DnaA domain I, which exhibits substantial sequence variation across bacteria. Notably, although the DnaA domain I has been shown to be essential, its contributions to initiation are not completely understood. Importantly, studies have indicated a role for DnaA domain I dimerization in the cooperative assembly of the initiation complex at the origin. However, the mechanism(s) and molecular basis of DnaA domain I dimerization have proved elusive. Here, we report structures of the DnaA domain I from ten Actinobacterial species. Strikingly, all structures reveal the same, unique dimer, and key elements which support DnaA domain I self-interaction are broadly conserved across the class Actinomycetes. Further, a suite of biochemical oligomerization assays and HDX-MS studies support the structural dimer. These findings suggest weak dimerization, as mediated by the DnaA domain I, acts a fine-tuned trigger in cooperative oriC assembly and that this is a broadly conserved biological mechanism for replication initiation in the class Actinomycetes.
2026-05-27 | PXD074705 | Pride
Project description:Initiation of DNA replication requires binding of the initiator protein, DnaA, to specific binding sites in the chromosomal origin of replication, oriC. In low G+C Gram-positive bacteria, the primosomal proteins DnaD and DnaB, in conjunction with loader ATPase DnaI, load the replicative helicase at oriC, and this depends on DnaA. DnaD and DnaB are also required to load the replicative helicase outside of oriC during replication restart, in a DnaA-independent manner. DnaA also binds to many sites around the chromosome, outside of oriC, and acts as a transcription factor at several of these. Using chromatin immunoprecipitation, we found that DnaD and DnaB, but not the replicative helicase, are associated with many of the chromosomal regions bound by DnaA in vivo in Bacillus subtilis. This association was dependent on DnaA and the order of recruitment was the same as that at oriC, but was independent of a functional oriC. The presence of DnaD and DnaB at the secondary (non-oriC) targets of DnaA in the absence of helicase loading indicates a possible role for DnaD and DnaB in modulating the activity of DnaA. The genome-wide binding profiles of DnaA, DnaD, DnaB and DnaC were determined. Binding profiles were determined in exponentially growing cells with and without HPUra treatment. Three biological replicates were analyzed per protein/treatment (one per array). Enrichment in immunoprecipitated samples versus total genomic DNA were determined.
2010-12-07 | E-GEOD-23686 | biostudies-arrayexpress
Project description:ChIP-seq was performed to map the association of SPA-tagged DnaA across the Escherichia coli MG1655 chromosome during exponential phase growth in LB. As a control to remove background, ChIP-Seq was also performed on SPA-tagged AcpS, a protein that is not known to bind DNA.
2022-10-16 | E-MTAB-12223 | biostudies-arrayexpress
Project description:Supporting data for Hottes et al., "DnaA coordinates replication initiation and cell cycle transcription in Caulobacter crescentus" The microarray component of this work monitors mRNA expression during the cell cycle of synchronized populations of Caulobacter crescentus cells. Transcription during the normal cell cycle is compared with transcription during a cell cycle where expression of dnaA, which encodes a key DNA replication initiation factor, is delayed. Keywords: time course, cell cycle, metabolism
2005-12-08 | GSE3171 | GEO