New members of the ctrA regulon: the major chemotaxis operon in Caulobacter is CtrA dependent

Jones, Susan; Ferguson, Natalie; Alley, M.R.K.

doi:10.1099/00221287-147-4-949

Cited by 22 publications

(18 citation statements)

References 47 publications

(52 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Importantly, however, they are not essential for filament assembly. FljJ and FljO were detected with the least efficiency by MALDI-TOF, consistent with previous data on fljJ and fljO expression levels (15,21). The only time FljJ was detected by MALDI-TOF was in the ⌬fljKL mutant combinations, i.e., when the other ␣-flagellins were absent.…”

Section: Resultssupporting

confidence: 79%

Flagellin Redundancy in Caulobacter crescentus and Its Implications for Flagellar Filament Assembly

et al. 2011

View full text Add to dashboard Cite

Section: Resultssupporting

confidence: 79%

Flagellin Redundancy in Caulobacter crescentus and Its Implications for Flagellar Filament Assembly

et al. 2011

View full text Add to dashboard Cite

“…These data suggest that the induction of genes in these clusters is driven predominantly by CtrA. For three of the genes in these two clusters (the ccrM gene encoding the CcrM DNA methyltransferase, the pilA gene encoding the major pilin subunit, and mcpA, encoding the McpA chemoreceptor), direct activation by CtrA has been verified (5,6,8,21).…”

Section: Resultsmentioning

confidence: 77%

Genes directly controlled by CtrA, a master regulator of the Caulobacter cell cycle

Laub

Chen

Shapiro

et al. 2002

Proc. Natl. Acad. Sci. U.S.A.

367

450

View full text Add to dashboard Cite

Studies of the genetic network that controls the Caulobacter cell cycle have identified a response regulator, CtrA, that controls, directly or indirectly, one-quarter of the 553 cell cycle-regulated genes. We have performed in vivo genomic binding site analysis of the CtrA protein to identify which of these genes have regulatory regions bound directly by CtrA. By combining these data with previous global analysis of cell cycle transcription patterns and gene expression profiles of mutant ctrA strains, we have determined that CtrA directly regulates at least 95 genes. The total group of CtrA-regulated genes includes those involved in polar morphogenesis, DNA replication initiation, DNA methylation, cell division, and cell wall metabolism. Also among the genes in this notably large regulon are 14 that encode regulatory proteins, including 10 two-component signal transduction regulatory proteins. Identification of additional regulatory genes activated by CtrA will serve to directly connect new regulatory modules to the network controlling cell cycle progression.

show abstract

“…Accordingly, while CC1574 transcription remains constant, MotB/CC1573 transcription varies during the cell cycle (13,14). The transcription of MotB/CC1573 peaks in dividing stalked cells coincident with the transcription of genes encoding other flagellar and chemotaxis proteins that are regulated by CtrA (11). The DNA immediately preceding MotB/CC1573 resembles the DNA containing the ctrA P1 and P2 promoters (Fig.…”

Section: Resultsmentioning

confidence: 94%

“…In both the ctrA P1 promoter and the fliX promoter, the length of the CtrA footprint over the one TTAA motif is about one-half the length of the CtrA footprint over a consensus TTAA-N7-TTAA site (24,25,31). Also, the major C. crescentus chemotaxis operons have two promoters that appear to use only single TTAA motifs (11). A genome-wide ChIP assay also suggested that some C. crescentus genes might use atypical or isolated TTAA motifs in their promoters (13).…”

Section: Discussionmentioning

confidence: 99%

CtrA, a Global Response Regulator, Uses a Distinct Second Category of Weak DNA Binding Sites for Cell Cycle Transcription Control in Caulobacter crescentus

et al. 2009

View full text Add to dashboard Cite

CtrA controls cell cycle programs of chromosome replication and genetic transcription. Phosphorylated CtrAϳP exhibits high affinity (dissociation constant [K d ], <10 nM) for consensus TTAA-N7-TTAA binding sites with "typical" (N ‫؍‬ 7) spacing. We show here that ctrA promoters P1 and P2 use low-affinity (K d , >500 nM) CtrA binding sites with "atypical" (N 7) spacing. Footprints demonstrated that phosphorylated CtrAϳP does not exhibit increased affinity for "atypical" sites, as it does for sites in the replication origin. Instead, high levels of CtrA (>10 M) accumulate, which can drive CtrA binding to "atypical" sites. In vivo cross-linking showed that when the stable CtrA⌬3 protein persists during the cell cycle, the "atypical" sites at ctrA and motB are persistently bound. Interestingly, the cell cycle timing of ctrA P1 and P2 transcription is not altered by persistent CtrA⌬3 binding. Therefore, operator DNA occupancy is not sufficient for regulation, and it is the cell cycle variation of CtrAϳP phosphorylation that provides the dominant "activation" signal. Protein dimerization is one potential means of "activation." The glutathione S-transferase (GST) protein dimerizes, and fusion with CtrA (GST-CtrA) creates a stable dimer with enhanced affinity for TTAA motifs. Electrophoretic mobility shift assays with GST-CtrA revealed cooperative modes of binding that further distinguish the "atypical" sites. GST-CtrA also binds a single TTAA motif in ctrA P1 aided by DNA in the extended TTAACCAT motif. We discuss how "atypical" sites are a common yet distinct category of CtrA regulatory sites and new implications for the working and evolution of cell cycle control networks.

show abstract

New members of the ctrA regulon: the major chemotaxis operon in Caulobacter is CtrA dependent

Cited by 22 publications

References 47 publications

Flagellin Redundancy in Caulobacter crescentus and Its Implications for Flagellar Filament Assembly

Flagellin Redundancy in Caulobacter crescentus and Its Implications for Flagellar Filament Assembly

Genes directly controlled by CtrA, a master regulator of the Caulobacter cell cycle

CtrA, a Global Response Regulator, Uses a Distinct Second Category of Weak DNA Binding Sites for Cell Cycle Transcription Control in Caulobacter crescentus

Contact Info

Product

Resources

About