ArticleJournal of bacteriology2013
Characterization of the ospZ promoter in Shigella flexneri and its regulation by VirB and H-NS.
Article in Journal of bacteriology, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 18 papers.
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Who cites it
18 citing papers in PubMed, 25 citations in OpenAlex.
- The role of the VirB ligand CTP in the molecular mechanism of transcriptional anti-silencing in Shigella flexneri.Nucleic acids research · 2026Article
- Remote Regulation by VirB, the Transcriptional Anti-Silencer of Shigella Virulence Genes, Provides Mechanistic Information.Molecular microbiology · 2025Article
- The virulence regulator VirB from Shigella flexneri uses a CTP-dependent switch mechanism to activate gene expression.Nature communications · 2024Article
- VirB, a transcriptional activator of virulence in Shigella flexneri, uses CTP as a cofactor.Communications biology · 2023Article
- VirB, a key transcriptional regulator ofmBio · 2023Article
- A Tale aboutMicroorganisms · 2023Review
- VirB, a key transcriptional regulator ofbioRxiv : the preprint server for biology · 2023Article
- Localized modulation of DNA supercoiling, triggered by the Shigella anti-silencer VirB, is sufficient to relieve H-NS-mediated silencing.Nucleic acids research · 2023Article
- Article
- The AraC/XylS Protein MxiE and Its Coregulator IpgC Control a Negative Feedback Loop in the Transcriptional Cascade That Regulates Type III Secretion in Shigella flexneri.Journal of bacteriology · 2022Article
- VirB, a key transcriptional regulator of virulence plasmid genes inJournal of bacteriology · 2021Article
- The T3SS ofMicroorganisms · 2020Review
- The Antiactivator of Type III Secretion, OspD1, Is Transcriptionally Regulated by VirB and H-NS from Remote Sequences in Shigella flexneri.Journal of bacteriology · 2020Article
- Article
- Insights into transcriptional silencing and anti-silencing in Shigella flexneri: a detailed molecular analysis of the icsP virulence locus.Molecular microbiology · 2018Article
- Regulatory Hierarchies Controlling Virulence Gene Expression inFrontiers in microbiology · 2018Review
- Review
- Characterization of SlyA in Shigella flexneri Identifies a Novel Role in Virulence.Infection and immunity · 2016Article
Corrections and comments
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Authors and funding
10 authors at 3 institutions in 2 countries.
Funding
Abstract
OspZ is an effector protein of the type III secretion system in Shigella spp. that downregulates the human inflammatory response during bacterial infection. The ospZ gene is located on the large virulence plasmid of Shigella. Many genes on this plasmid are transcriptionally repressed by the nucleoid structuring protein H-NS and derepressed by VirB, a DNA-binding protein that displays homology to the plasmid partitioning proteins ParB and SopB. In this study, we characterized the ospZ promoter and investigated its regulation by H-NS and VirB in Shigella flexneri. We show that H-NS represses and VirB partially derepresses the ospZ promoter. H-NS-mediated repression requires sequences located between -731 and -412 relative to the beginning of the ospZ gene. Notably, the VirB-dependent derepression of ospZ requires the same VirB binding sites as are required for the VirB-dependent derepression of the divergent icsP gene. These sites are centered 425 bp upstream of the ospZ gene but over 1 kb upstream of the icsP transcription start site. Although these VirB binding sites lie closer to ospZ than icsP, the VirB-dependent increase in ospZ promoter activity is lower than that observed at the icsP promoter. This indicates that the proximity of VirB binding sites to Shigella promoters does not necessarily correlate with the level of VirB-dependent derepression. These findings have implications for virulence gene regulation in Shigella and other pathogens that control gene expression using mechanisms of transcriptional repression and derepression.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.