1
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Wiedermannová J, Babu R, Yuzenkova Y. Stochastic nature and physiological implications of 5'-NAD RNA cap in bacteria. Nucleic Acids Res 2024:gkae813. [PMID: 39325642 DOI: 10.1093/nar/gkae813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 08/30/2024] [Accepted: 09/07/2024] [Indexed: 09/28/2024] Open
Abstract
RNA 5'-modification with NAD+/NADH (oxidized/reduced nicotinamide adenine dinucleotide) has been found in bacteria, eukaryotes and viruses. 5'-NAD is incorporated into RNA by RNA polymerases (RNAPs) during the initiation of synthesis. It is unknown (i) which factors and physiological conditions permit substantial NAD incorporation into RNA in vivo and (ii) how 5'-NAD impacts gene expression and the fate of RNA in bacteria. Here we show in Escherichia coli that RNA NADylation is stimulated by low cellular concentration of the competing substrate ATP, and by weakening ATP contacts with RNAP active site. Additionally, RNA NADylation may be influenced by DNA supercoiling. RNA NADylation does not interfere with posttranscriptional RNA processing by major ribonuclease RNase E. It does not impact the base-pairing between RNAI, the repressor of plasmid replication, and its antisense target, RNAII. Leaderless NADylated model mRNA cI-lacZ is recognized by the 70S ribosome and is translated with the same efficiency as triphosphorylated cI-lacZ mRNA. Translation exposes the 5'-NAD of this mRNA to de-capping by NudC enzyme. We suggest that NADylated mRNAs are rapidly degraded, consistent with their low abundance in published datasets. Furthermore, we observed that ppGpp inhibits NudC de-capping activity, contributing to the growth phase-dependency of NADylated RNA levels.
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Affiliation(s)
- Jana Wiedermannová
- Centre for Bacterial Cell Biology, Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4AX, UK
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic
| | - Ravishankar Babu
- Centre for Bacterial Cell Biology, Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4AX, UK
| | - Yulia Yuzenkova
- Centre for Bacterial Cell Biology, Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4AX, UK
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2
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Qiu Y, Xiang L, Yin M, Fang C, Dai X, Zhang L, Li Y. RfaH contributes to maximal colonization and full virulence of hypervirulent Klebsiella pneumoniae. Front Cell Infect Microbiol 2024; 14:1454373. [PMID: 39364146 PMCID: PMC11448354 DOI: 10.3389/fcimb.2024.1454373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2024] [Accepted: 08/19/2024] [Indexed: 10/05/2024] Open
Abstract
Hypervirulent K. pneumoniae (hvKp) have emerged as clinically important pathogens, posing a serious threat to human health. RfaH, a transcriptional elongation factor, has been regarded as implicated in facilitating the transcription of long virulence operons in certain bacterial species. In K. pneumoniae, RfaH plays a vital role in promoting CPS synthesis and hypermucoviscosity, as well as mediating bacterial fitness during lung infection. In this study, we aim to conduct a systematic investigation of the roles of rfaH in the survival, dissemination, and colonization of hvKp through in vitro and in vivo assays. We found that bacterial cells and colonies displayed capsule -deficient phenotypes subsequent to the deletion of rfaH in K. pneumoniae NTUH-K2044. We confirmed that rfaH is required for the synthesis of capsule and lipopolysaccharide (LPS) by positively regulating the expression of CPS and LPS gene clusters. We found that the ΔrfaH mutant led to a significantly decreased mortality of K. pneumoniae in a mouse intraperitoneal infection model. We further demonstrated that the absence of rfaH was associated with slower bacterial growth under conditions of low nutrition or iron limitation. ΔrfaH displayed reduced survival rates in the presence of human serum. Besides, the engulfment of the ΔrfaH mutant was significantly higher than that of NTUH-K2044 by macrophages in vivo, indicating an indispensable role of RfaH in the phagocytosis resistance of hvKp in mice. Both mouse intranasal and intraperitoneal infection models revealed a higher bacterial clearance rate of ΔrfaH in lungs, livers, and spleens of mice compared to its wild type, suggesting an important role of RfaH in the bacterial survival, dissemination, and colonization of hvKp in vivo. Histopathological results supported that RfaH contributes to the pathogenicity of hvKp in mice. In conclusion, our study demonstrates crucial roles of RfaH in the survival, colonization and full virulence of hvKp, which provides several implications for the development of RfaH as an antibacterial target.
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Affiliation(s)
- Yichuan Qiu
- Department of Clinical Laboratory, Hospital of Chengdu Office of People’s Government of Tibetan Autonomous Region, Chengdu, Sichuan, China
| | - Li Xiang
- The School of Basic Medical Sciences, Southwest Medical University, Luzhou, Sichuan, China
| | - Ming Yin
- The School of Basic Medical Sciences, Southwest Medical University, Luzhou, Sichuan, China
| | - Chengju Fang
- The School of Basic Medical Sciences, Southwest Medical University, Luzhou, Sichuan, China
| | - Xiaoyi Dai
- The School of Basic Medical Sciences, Southwest Medical University, Luzhou, Sichuan, China
| | - Luhua Zhang
- The School of Basic Medical Sciences, Southwest Medical University, Luzhou, Sichuan, China
| | - Ying Li
- The School of Basic Medical Sciences, Southwest Medical University, Luzhou, Sichuan, China
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3
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Cooper C, Legood S, Wheat RL, Forrest D, Sharma P, Haycocks JRJ, Grainger DC. H-NS is a bacterial transposon capture protein. Nat Commun 2024; 15:7137. [PMID: 39164300 PMCID: PMC11335895 DOI: 10.1038/s41467-024-51407-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Accepted: 08/05/2024] [Indexed: 08/22/2024] Open
Abstract
The histone-like nucleoid structuring (H-NS) protein is a DNA binding factor, found in gammaproteobacteria, with functional equivalents in diverse microbes. Universally, such proteins are understood to silence transcription of horizontally acquired genes. Here, we identify transposon capture as a major overlooked function of H-NS. Using genome-scale approaches, we show that H-NS bound regions are transposition "hotspots". Since H-NS often interacts with pathogenicity islands, such targeting creates clinically relevant phenotypic diversity. For example, in Acinetobacter baumannii, we identify altered motility, biofilm formation, and interactions with the human immune system. Transposon capture is mediated by the DNA bridging activity of H-NS and, if absent, more ubiquitous transposition results. Consequently, transcribed and essential genes are disrupted. Hence, H-NS directs transposition to favour evolutionary outcomes useful for the host cell.
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Affiliation(s)
- Charles Cooper
- School of Biosciences, University of Birmingham, Birmingham, UK
| | - Simon Legood
- School of Biosciences, University of Birmingham, Birmingham, UK
| | - Rachel L Wheat
- School of Biosciences, University of Birmingham, Birmingham, UK
| | - David Forrest
- School of Biosciences, University of Birmingham, Birmingham, UK
| | - Prateek Sharma
- School of Biosciences, University of Birmingham, Birmingham, UK
| | | | - David C Grainger
- School of Biosciences, University of Birmingham, Birmingham, UK.
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4
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Blombach F, Werner F. Chromatin and gene regulation in archaea. Mol Microbiol 2024. [PMID: 39096085 DOI: 10.1111/mmi.15302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Revised: 07/12/2024] [Accepted: 07/16/2024] [Indexed: 08/04/2024]
Abstract
The chromatinisation of DNA by nucleoid-associated proteins (NAPs) in archaea 'formats' the genome structure in profound ways, revealing both striking differences and analogies to eukaryotic chromatin. However, the extent to which archaeal NAPs actively regulate gene expression remains poorly understood. The dawn of quantitative chromatin mapping techniques and first NAP-specific occupancy profiles in different archaea promise a more accurate view. A picture emerges where in diverse archaea with very different NAP repertoires chromatin maintains access to regulatory motifs including the gene promoter independently of transcription activity. Our re-analysis of genome-wide occupancy data of the crenarchaeal NAP Cren7 shows that these chromatin-free regions are flanked by increased Cren7 binding across the transcription start site. While bacterial NAPs often form heterochromatin-like regions across islands with xenogeneic genes that are transcriptionally silenced, there is little evidence for similar structures in archaea and data from Haloferax show that the promoters of xenogeneic genes remain accessible. Local changes in chromatinisation causing wide-ranging effects on transcription restricted to one chromosomal interaction domain (CID) in Saccharolobus islandicus hint at a higher-order level of organisation between chromatin and transcription. The emerging challenge is to integrate results obtained at microscale and macroscale, reconciling molecular structure and function with dynamic genome-wide chromatin landscapes.
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Affiliation(s)
- Fabian Blombach
- Division of Biosciences, RNAP Laboratory, Institute of Structural and Molecular Biology (ISMB), University College London, London, UK
| | - Finn Werner
- Division of Biosciences, RNAP Laboratory, Institute of Structural and Molecular Biology (ISMB), University College London, London, UK
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5
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Hustmyer CM, Landick R. Bacterial chromatin proteins, transcription, and DNA topology: Inseparable partners in the control of gene expression. Mol Microbiol 2024; 122:81-112. [PMID: 38847475 PMCID: PMC11260248 DOI: 10.1111/mmi.15283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 05/10/2024] [Accepted: 05/13/2024] [Indexed: 06/15/2024]
Abstract
DNA in bacterial chromosomes is organized into higher-order structures by DNA-binding proteins called nucleoid-associated proteins (NAPs) or bacterial chromatin proteins (BCPs). BCPs often bind to or near DNA loci transcribed by RNA polymerase (RNAP) and can either increase or decrease gene expression. To understand the mechanisms by which BCPs alter transcription, one must consider both steric effects and the topological forces that arise when DNA deviates from its fully relaxed double-helical structure. Transcribing RNAP creates DNA negative (-) supercoils upstream and positive (+) supercoils downstream whenever RNAP and DNA are unable to rotate freely. This (-) and (+) supercoiling generates topological forces that resist forward translocation of DNA through RNAP unless the supercoiling is constrained by BCPs or relieved by topoisomerases. BCPs also may enhance topological stress and overall can either inhibit or aid transcription. Here, we review current understanding of how RNAP, BCPs, and DNA topology interplay to control gene expression.
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Affiliation(s)
| | - Robert Landick
- Department of Biochemistry, University of Wisconsin-Madison
- Department of Bacteriology, University of Wisconsin-Madison
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6
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Raustad N, Dai Y, Iinishi A, Mohapatra A, Soo MW, Hay E, Hernandez GM, Geisinger E. A phosphorylation signal activates genome-wide transcriptional control by BfmR, the global regulator of Acinetobacter resistance and virulence. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.16.599214. [PMID: 38948834 PMCID: PMC11212878 DOI: 10.1101/2024.06.16.599214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
The nosocomial pathogen Acinetobacter baumannii is a major threat to human health. The sensor kinase-response regulator system, BfmS-BfmR, is essential to multidrug resistance and virulence in the bacterium and represents a potential antimicrobial target. Important questions remain about how the system controls resistance and pathogenesis. Although BfmR knockout alters expression of >1000 genes, its direct regulon is undefined. Moreover, how phosphorylation controls the regulator is unclear. Here, we address these problems by combining mutagenesis, ChIP-seq, and in vitro phosphorylation to study the functions of phospho-BfmR. We show that phosphorylation is required for BfmR-mediated gene regulation, antibiotic resistance, and sepsis development in vivo. Consistent with activating the protein, phosphorylation induces dimerization and target DNA affinity. Integrated analysis of genome-wide binding and transcriptional profiles of BfmR led to additional key findings: (1) Phosphorylation dramatically expands the number of genomic sites BfmR binds; (2) DNA recognition involves a direct repeat motif widespread across promoters; (3) BfmR directly regulates 303 genes as activator (eg, capsule, peptidoglycan, and outer membrane biogenesis) or repressor (pilus biogenesis); (4) BfmR controls several non-coding sRNAs. These studies reveal the centrality of a phosphorylation signal in driving A. baumannii disease and disentangle the extensive pathogenic gene-regulatory network under its control.
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Affiliation(s)
- Nicole Raustad
- Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Yunfei Dai
- Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Akira Iinishi
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Arpita Mohapatra
- Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Mark W. Soo
- Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Everett Hay
- Department of Biology, Northeastern University, Boston, MA 02115, USA
| | | | - Edward Geisinger
- Department of Biology, Northeastern University, Boston, MA 02115, USA
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7
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Ekdahl AM, Julien T, Suraj S, Kribelbauer J, Tavazoie S, Freddolino PL, Contreras LM. Multiscale regulation of nutrient stress responses in Escherichia coli from chromatin structure to small regulatory RNAs. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.20.599902. [PMID: 38979244 PMCID: PMC11230228 DOI: 10.1101/2024.06.20.599902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Recent research has indicated the presence of heterochromatin-like regions of extended protein occupancy and transcriptional silencing of bacterial genomes. We utilized an integrative approach to track chromatin structure and transcription in E. coli K-12 across a wide range of nutrient conditions. In the process, we identified multiple loci which act similarly to facultative heterochromatin in eukaryotes, normally silenced but permitting expression of genes under specific conditions. We also found a strong enrichment of small regulatory RNAs (sRNAs) among the set of differentially expressed transcripts during nutrient stress. Using a newly developed bioinformatic pipeline, the transcription factors regulating sRNA expression were bioinformatically predicted, with experimental follow-up revealing novel relationships for 36 sRNA-transcription factors candidates. Direct regulation of sRNA expression was confirmed by mutational analysis for five sRNAs of metabolic interest: IsrB, CsrB and CsrC, GcvB, and GadY. Our integrative analysis thus reveals additional layers of complexity in the nutrient stress response in E. coli and provides a framework for revealing similar poorly understood regulatory logic in other organisms.
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Affiliation(s)
- Alyssa M Ekdahl
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, TX 78712, USA
| | - Tatiana Julien
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX, 78712, USA
| | - Sahana Suraj
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, TX 78712, USA
| | - Judith Kribelbauer
- Department of Systems Biology, Columbia University, New York, NY, 10032, USA
| | - Saeed Tavazoie
- Department of Systems Biology, Columbia University, New York, NY, 10032, USA
| | - P Lydia Freddolino
- Department of Biological Chemistry and Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Lydia M Contreras
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, TX 78712, USA
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8
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Li Y, Wei X, Yang Q, Xiong A, Li X, Zou Q, Cui F, Zhang Z. msBERT-Promoter: a multi-scale ensemble predictor based on BERT pre-trained model for the two-stage prediction of DNA promoters and their strengths. BMC Biol 2024; 22:126. [PMID: 38816885 DOI: 10.1186/s12915-024-01923-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 05/21/2024] [Indexed: 06/01/2024] Open
Abstract
BACKGROUND A promoter is a specific sequence in DNA that has transcriptional regulatory functions, playing a role in initiating gene expression. Identifying promoters and their strengths can provide valuable information related to human diseases. In recent years, computational methods have gained prominence as an effective means for identifying promoter, offering a more efficient alternative to labor-intensive biological approaches. RESULTS In this study, a two-stage integrated predictor called "msBERT-Promoter" is proposed for identifying promoters and predicting their strengths. The model incorporates multi-scale sequence information through a tokenization strategy and fine-tunes the DNABERT model. Soft voting is then used to fuse the multi-scale information, effectively addressing the issue of insufficient DNA sequence information extraction in traditional models. To the best of our knowledge, this is the first time an integrated approach has been used in the DNABERT model for promoter identification and strength prediction. Our model achieves accuracy rates of 96.2% for promoter identification and 79.8% for promoter strength prediction, significantly outperforming existing methods. Furthermore, through attention mechanism analysis, we demonstrate that our model can effectively combine local and global sequence information, enhancing its interpretability. CONCLUSIONS msBERT-Promoter provides an effective tool that successfully captures sequence-related attributes of DNA promoters and can accurately identify promoters and predict their strengths. This work paves a new path for the application of artificial intelligence in traditional biology.
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Affiliation(s)
- Yazi Li
- School of Mathematics and Statistics, Hainan University, Haikou, 570228, China
| | - Xiaoman Wei
- School of Computer Science and Technology, Hainan University, Haikou, 570228, China
| | - Qinglin Yang
- School of Computer Science and Technology, Hainan University, Haikou, 570228, China
| | - An Xiong
- School of Computer Science and Technology, Hainan University, Haikou, 570228, China
| | - Xingfeng Li
- School of Computer Science and Technology, Hainan University, Haikou, 570228, China
| | - Quan Zou
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, 610054, China
- Yangtze Delta Region Institute (Quzhou), University of Electronic Science and Technology of China, Quzhou, 324000, China
| | - Feifei Cui
- School of Computer Science and Technology, Hainan University, Haikou, 570228, China.
| | - Zilong Zhang
- School of Computer Science and Technology, Hainan University, Haikou, 570228, China.
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9
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uz-Zaman MH, D’Alton S, Barrick JE, Ochman H. Promoter recruitment drives the emergence of proto-genes in a long-term evolution experiment with Escherichia coli. PLoS Biol 2024; 22:e3002418. [PMID: 38713714 PMCID: PMC11101190 DOI: 10.1371/journal.pbio.3002418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 05/17/2024] [Accepted: 04/18/2024] [Indexed: 05/09/2024] Open
Abstract
The phenomenon of de novo gene birth-the emergence of genes from non-genic sequences-has received considerable attention due to the widespread occurrence of genes that are unique to particular species or genomes. Most instances of de novo gene birth have been recognized through comparative analyses of genome sequences in eukaryotes, despite the abundance of novel, lineage-specific genes in bacteria and the relative ease with which bacteria can be studied in an experimental context. Here, we explore the genetic record of the Escherichia coli long-term evolution experiment (LTEE) for changes indicative of "proto-genic" phases of new gene birth in which non-genic sequences evolve stable transcription and/or translation. Over the time span of the LTEE, non-genic regions are frequently transcribed, translated and differentially expressed, with levels of transcription across low-expressed regions increasing in later generations of the experiment. Proto-genes formed downstream of new mutations result either from insertion element activity or chromosomal translocations that fused preexisting regulatory sequences to regions that were not expressed in the LTEE ancestor. Additionally, we identified instances of proto-gene emergence in which a previously unexpressed sequence was transcribed after formation of an upstream promoter, although such cases were rare compared to those caused by recruitment of preexisting promoters. Tracing the origin of the causative mutations, we discovered that most occurred early in the history of the LTEE, often within the first 20,000 generations, and became fixed soon after emergence. Our findings show that proto-genes emerge frequently within evolving populations, can persist stably, and can serve as potential substrates for new gene formation.
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Affiliation(s)
- Md. Hassan uz-Zaman
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, United States of America
| | - Simon D’Alton
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, United States of America
| | - Jeffrey E. Barrick
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, United States of America
| | - Howard Ochman
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, United States of America
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10
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Blanco P, Hipólito A, García-Pastor L, Trigo da Roza F, Toribio-Celestino L, Ortega A, Vergara E, San Millán Á, Escudero J. Identification of promoter activity in gene-less cassettes from Vibrionaceae superintegrons. Nucleic Acids Res 2024; 52:2961-2976. [PMID: 38214222 PMCID: PMC11014356 DOI: 10.1093/nar/gkad1252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 12/18/2023] [Accepted: 12/26/2023] [Indexed: 01/13/2024] Open
Abstract
Integrons are genetic platforms that acquire new genes encoded in integron cassettes (ICs), building arrays of adaptive functions. ICs generally encode promoterless genes, whose expression relies on the platform-associated Pc promoter, with the cassette array functioning as an operon-like structure regulated by the distance to the Pc. This is relevant in large sedentary chromosomal integrons (SCIs) carrying hundreds of ICs, like those in Vibrio species. We selected 29 gene-less cassettes in four Vibrio SCIs, and explored whether their function could be related to the transcription regulation of adjacent ICs. We show that most gene-less cassettes have promoter activity on the sense strand, enhancing the expression of downstream cassettes. Additionally, we identified the transcription start sites of gene-less ICs through 5'-RACE. Accordingly, we found that most of the superintegron in Vibrio cholerae is not silent. These promoter cassettes can trigger the expression of a silent dfrB9 cassette downstream, increasing trimethoprim resistance >512-fold in V. cholerae and Escherichia coli. Furthermore, one cassette with an antisense promoter can reduce trimethoprim resistance when cloned downstream. Our findings highlight the regulatory role of gene-less cassettes in the expression of adjacent cassettes, emphasizing their significance in SCIs and their clinical importance if captured by mobile integrons.
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Affiliation(s)
- Paula Blanco
- Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid 28040, Spain
- VISAVET Health Surveillance Centre, Universidad Complutense de Madrid, Madrid 28040, Spain
| | - Alberto Hipólito
- Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid 28040, Spain
- VISAVET Health Surveillance Centre, Universidad Complutense de Madrid, Madrid 28040, Spain
| | - Lucía García-Pastor
- Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid 28040, Spain
- VISAVET Health Surveillance Centre, Universidad Complutense de Madrid, Madrid 28040, Spain
| | - Filipa Trigo da Roza
- Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid 28040, Spain
- VISAVET Health Surveillance Centre, Universidad Complutense de Madrid, Madrid 28040, Spain
| | - Laura Toribio-Celestino
- Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Madrid 28049, Spain
| | - Alba Cristina Ortega
- Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid 28040, Spain
| | - Ester Vergara
- Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid 28040, Spain
- VISAVET Health Surveillance Centre, Universidad Complutense de Madrid, Madrid 28040, Spain
| | - Álvaro San Millán
- Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Madrid 28049, Spain
- Centro de Investigación Biológica en Red de Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III, Madrid 28222, Spain
| | - José Antonio Escudero
- Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid 28040, Spain
- VISAVET Health Surveillance Centre, Universidad Complutense de Madrid, Madrid 28040, Spain
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11
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Figueroa-Bossi N, Fernández-Fernández R, Kerboriou P, Bouloc P, Casadesús J, Sánchez-Romero MA, Bossi L. Transcription-driven DNA supercoiling counteracts H-NS-mediated gene silencing in bacterial chromatin. Nat Commun 2024; 15:2787. [PMID: 38555352 PMCID: PMC10981669 DOI: 10.1038/s41467-024-47114-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 03/19/2024] [Indexed: 04/02/2024] Open
Abstract
In all living cells, genomic DNA is compacted through interactions with dedicated proteins and/or the formation of plectonemic coils. In bacteria, DNA compaction is achieved dynamically, coordinated with dense and constantly changing transcriptional activity. H-NS, a major bacterial nucleoid structuring protein, is of special interest due to its interplay with RNA polymerase. H-NS:DNA nucleoprotein filaments inhibit transcription initiation by RNA polymerase. However, the discovery that genes silenced by H-NS can be activated by transcription originating from neighboring regions has suggested that elongating RNA polymerases can disassemble H-NS:DNA filaments. In this study, we present evidence that transcription-induced counter-silencing does not require transcription to reach the silenced gene; rather, it exerts its effect at a distance. Counter-silencing is suppressed by introducing a DNA gyrase binding site within the intervening segment, suggesting that the long-range effect results from transcription-driven positive DNA supercoils diffusing toward the silenced gene. We propose a model wherein H-NS:DNA complexes form in vivo on negatively supercoiled DNA, with H-NS bridging the two arms of the plectoneme. Rotational diffusion of positive supercoils generated by neighboring transcription will cause the H-NS-bound negatively-supercoiled plectoneme to "unroll" disrupting the H-NS bridges and releasing H-NS.
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Affiliation(s)
- Nara Figueroa-Bossi
- Université Paris-Saclay, CEA, CNRS, Institut de Biologie Intégrative de la Cellule (I2BC), Gif-sur-Yvette, France
| | - Rocío Fernández-Fernández
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad de Sevilla, Sevilla, Spain
| | - Patricia Kerboriou
- Université Paris-Saclay, CEA, CNRS, Institut de Biologie Intégrative de la Cellule (I2BC), Gif-sur-Yvette, France
| | - Philippe Bouloc
- Université Paris-Saclay, CEA, CNRS, Institut de Biologie Intégrative de la Cellule (I2BC), Gif-sur-Yvette, France
| | - Josep Casadesús
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Sevilla, Spain
| | | | - Lionello Bossi
- Université Paris-Saclay, CEA, CNRS, Institut de Biologie Intégrative de la Cellule (I2BC), Gif-sur-Yvette, France.
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12
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Gerges E, Herrmann JL, Crémazy F. [Lsr2: A Nucleoid Associated Protein (NAP) and a transcription factor in mycobacteria]. Med Sci (Paris) 2024; 40:154-160. [PMID: 38411423 DOI: 10.1051/medsci/2023218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024] Open
Abstract
Lsr2, a small protein mainly found in actinobacteria, plays a crucial role in the virulence and adaptation of mycobacteria to environmental conditions. As a member of the nucleoid-associated protein (NAPs) superfamily, Lsr2 influences DNA organization by facilitating the formation of chromosomal loops in vitro and, therefore, may be a major player in the three-dimensional folding of the genome. Additionally, Lsr2 also acts as a transcription factor, regulating the expression of numerous genes responsible for coordinating a myriad of cellular and molecular processes essential for the actinobacteria. Similar to the H-NS protein, its ortholog in enterobacteria, its role in transcriptional repression likely relies on oligomerization, rigidifying, and bridging of DNA, thereby disrupting RNA polymerase recruitment as well as the elongation of RNA transcripts.
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Affiliation(s)
- Elias Gerges
- Université Paris-Saclay, UVSQ, Inserm, Infection et inflammation, 78180 Montigny-Le-Bretonneux, France
| | - Jean-Louis Herrmann
- Université Paris-Saclay, UVSQ, Inserm, Infection et inflammation, 78180 Montigny-Le-Bretonneux, France
| | - Frédéric Crémazy
- Université Paris-Saclay, UVSQ, Inserm, Infection et inflammation, 78180 Montigny-Le-Bretonneux, France
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13
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Grandchamp A, Czuppon P, Bornberg-Bauer E. Quantification and modeling of turnover dynamics of de novo transcripts in Drosophila melanogaster. Nucleic Acids Res 2024; 52:274-287. [PMID: 38000384 PMCID: PMC10783523 DOI: 10.1093/nar/gkad1079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 10/13/2023] [Accepted: 10/28/2023] [Indexed: 11/26/2023] Open
Abstract
Most of the transcribed eukaryotic genomes are composed of non-coding transcripts. Among these transcripts, some are newly transcribed when compared to outgroups and are referred to as de novo transcripts. De novo transcripts have been shown to play a major role in genomic innovations. However, little is known about the rates at which de novo transcripts are gained and lost in individuals of the same species. Here, we address this gap and estimate the de novo transcript turnover rate with an evolutionary model. We use DNA long reads and RNA short reads from seven geographically remote samples of inbred individuals of Drosophila melanogaster to detect de novo transcripts that are gained on a short evolutionary time scale. Overall, each sampled individual contains around 2500 unspliced de novo transcripts, with most of them being sample specific. We estimate that around 0.15 transcripts are gained per year, and that each gained transcript is lost at a rate around 5× 10-5 per year. This high turnover of transcripts suggests frequent exploration of new genomic sequences within species. These rate estimates are essential to comprehend the process and timescale of de novo gene birth.
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Affiliation(s)
- Anna Grandchamp
- Institute for Evolution and Biodiversity, University of Münster, Münster, Germany
| | - Peter Czuppon
- Institute for Evolution and Biodiversity, University of Münster, Münster, Germany
| | - Erich Bornberg-Bauer
- Institute for Evolution and Biodiversity, University of Münster, Münster, Germany
- Department of Protein Evolution, Max Planck Institute for Biology, Tübingen, Germany
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14
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Pospíšil J, Schwarz M, Ziková A, Vítovská D, Hradilová M, Kolář M, Křenková A, Hubálek M, Krásný L, Vohradský J. σ E of Streptomyces coelicolor can function both as a direct activator or repressor of transcription. Commun Biol 2024; 7:46. [PMID: 38184746 PMCID: PMC10771440 DOI: 10.1038/s42003-023-05716-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 12/18/2023] [Indexed: 01/08/2024] Open
Abstract
σ factors are considered as positive regulators of gene expression. Here we reveal the opposite, inhibitory role of these proteins. We used a combination of molecular biology methods and computational modeling to analyze the regulatory activity of the extracytoplasmic σE factor from Streptomyces coelicolor. The direct activator/repressor function of σE was then explored by experimental analysis of selected promoter regions in vivo. Additionally, the σE interactome was defined. Taken together, the results characterize σE, its regulation, regulon, and suggest its direct inhibitory function (as a repressor) in gene expression, a phenomenon that may be common also to other σ factors and organisms.
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Affiliation(s)
- Jiří Pospíšil
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic.
| | - Marek Schwarz
- Laboratory of Bioinformatics, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Alice Ziková
- Laboratory of Bioinformatics, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Dragana Vítovská
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Miluše Hradilová
- Laboratory of Genomics and Bioinformatics, Institute of Molecular Genetics of the Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Michal Kolář
- Laboratory of Genomics and Bioinformatics, Institute of Molecular Genetics of the Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Alena Křenková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nam. 542/2, 160 00, Prague 6, Czech Republic
| | - Martin Hubálek
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nam. 542/2, 160 00, Prague 6, Czech Republic
| | - Libor Krásný
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Jiří Vohradský
- Laboratory of Bioinformatics, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic.
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15
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Boudreau BA, Hustmyer CM, Kotlajich MV, Landick R. In Vitro Transcription Assay to Quantify Effects of H-NS Filaments on RNA Chain Elongation by RNA Polymerase. Methods Mol Biol 2024; 2819:381-419. [PMID: 39028516 DOI: 10.1007/978-1-0716-3930-6_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
Bacterial chromosomal DNA is structured and compacted by proteins known as bacterial chromatin proteins (i.e., nucleoid-associated proteins or NAPs). DNA-dependent RNA polymerase (RNAP) must frequently interact with bacterial chromatin proteins because they often bind DNA genome-wide. In some cases, RNAP must overcome barriers bacterial chromatin proteins impose on transcription. One key bacterial chromatin protein in Escherichia coli that influences transcription is the histone-like nucleoid structuring protein, H-NS. H-NS binds to DNA and forms nucleoprotein filaments. To investigate the effect of H-NS filaments on RNAP elongation, we developed an in vitro transcription assay to monitor RNAP progression on a DNA template bound by H-NS. In this method, initiation and elongation by RNAP are uncoupled by first initiating transcription in the presence of only three ribonucleoside triphosphates (rNTPs) to halt elongation just downstream of the promoter. Before elongation is restarted by addition of the fourth NTP, an H-NS filament is formed on the DNA so that transcript elongation occurs on an H-NS nucleoprotein filament template. Here, we provide detailed protocols for performing in vitro transcription through H-NS filaments, analysis of the transcription products, and visualization of H-NS filament formation on DNA by electrophoretic mobility shift assay (EMSA). These methods enable insight into how H-NS affects RNAP transcript elongation and provide a starting point to determine effects of other bacterial chromatin proteins on RNAP elongation.
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Affiliation(s)
- Beth A Boudreau
- Departments of Biochemistry, University of Wisconsin - Madison, Madison, WI, USA
| | - Christine M Hustmyer
- Departments of Biochemistry, University of Wisconsin - Madison, Madison, WI, USA
| | - Matthew V Kotlajich
- Departments of Biochemistry, University of Wisconsin - Madison, Madison, WI, USA
| | - Robert Landick
- Departments of Biochemistry, University of Wisconsin - Madison, Madison, WI, USA.
- Departments of Bacteriology, University of Wisconsin - Madison, Madison, WI, USA.
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16
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Hoareau M, Gerges E, Crémazy FGE. Shedding Light on Bacterial Chromosome Structure: Exploring the Significance of 3C-Based Approaches. Methods Mol Biol 2024; 2819:3-26. [PMID: 39028499 DOI: 10.1007/978-1-0716-3930-6_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
The complex architecture of DNA within living organisms is essential for maintaining the genetic information that dictates their functions and characteristics. Among the many complexities of genetic material organization, the folding and arrangement of DNA into chromosomes play a critical role in regulating gene expression, replication, and other essential cellular processes. Bacteria, despite their apparently simple cellular structure, exhibit a remarkable level of chromosomal organization that influences their adaptability and survival in diverse environments. Understanding the three-dimensional arrangement of bacterial chromosomes has long been a challenge due to technical limitations, but the development of Chromosome Conformation Capture (3C) methods revolutionized our ability to explore the hierarchical structure and the dynamics of bacterial genomes. Here, we review the major advances in the field of bacterial chromosome structure using 3C technology over the past decade.
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Affiliation(s)
- Marion Hoareau
- Université Paris-Saclay, UVSQ, Inserm, Infection et inflammation, Montigny-Le-Bretonneux, France
| | - Elias Gerges
- Université Paris-Saclay, UVSQ, Inserm, Infection et inflammation, Montigny-Le-Bretonneux, France
| | - Frédéric G E Crémazy
- Université Paris-Saclay, UVSQ, Inserm, Infection et inflammation, Montigny-Le-Bretonneux, France.
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17
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Rashid FZM, Crémazy FGE, Hofmann A, Forrest D, Grainger DC, Heermann DW, Dame RT. The environmentally-regulated interplay between local three-dimensional chromatin organisation and transcription of proVWX in E. coli. Nat Commun 2023; 14:7478. [PMID: 37978176 PMCID: PMC10656529 DOI: 10.1038/s41467-023-43322-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 11/07/2023] [Indexed: 11/19/2023] Open
Abstract
Nucleoid associated proteins (NAPs) maintain the architecture of bacterial chromosomes and regulate gene expression. Thus, their role as transcription factors may involve three-dimensional chromosome re-organisation. While this model is supported by in vitro studies, direct in vivo evidence is lacking. Here, we use RT-qPCR and 3C-qPCR to study the transcriptional and architectural profiles of the H-NS (histone-like nucleoid structuring protein)-regulated, osmoresponsive proVWX operon of Escherichia coli at different osmolarities and provide in vivo evidence for transcription regulation by NAP-mediated chromosome re-modelling in bacteria. By consolidating our in vivo investigations with earlier in vitro and in silico studies that provide mechanistic details of how H-NS re-models DNA in response to osmolarity, we report that activation of proVWX in response to a hyperosmotic shock involves the destabilization of H-NS-mediated bridges anchored between the proVWX downstream and upstream regulatory elements (DRE and URE), and between the DRE and ygaY that lies immediately downstream of proVWX. The re-establishment of these bridges upon adaptation to hyperosmolarity represses the operon. Our results also reveal additional structural features associated with changes in proVWX transcript levels such as the decompaction of local chromatin upstream of the operon, highlighting that further complexity underlies the regulation of this model operon. H-NS and H-NS-like proteins are wide-spread amongst bacteria, suggesting that chromosome re-modelling may be a typical feature of transcriptional control in bacteria.
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Affiliation(s)
- Fatema-Zahra M Rashid
- Macromolecular Biochemistry, Leiden Institute of Chemistry, Leiden University, Leiden, 2333CC, The Netherlands
- Centre for Microbial Cell Biology, Leiden University, Leiden, 2333CC, The Netherlands
- Centre for Interdisciplinary Genome Research, Leiden University, Leiden, 2333CC, The Netherlands
| | - Frédéric G E Crémazy
- Macromolecular Biochemistry, Leiden Institute of Chemistry, Leiden University, Leiden, 2333CC, The Netherlands
- Laboratoire Infection et Inflammation, INSERM, UVSQ, Université Paris-Saclay, Versailles, 78180, France
| | - Andreas Hofmann
- Statistical Physics and Theoretical Biophysics, Heidelberg University, Heidelberg, D-69120, Germany
| | - David Forrest
- School of Biosciences, University of Birmingham, Edgbaston, B15 2TT, UK
| | - David C Grainger
- School of Biosciences, University of Birmingham, Edgbaston, B15 2TT, UK
| | - Dieter W Heermann
- Statistical Physics and Theoretical Biophysics, Heidelberg University, Heidelberg, D-69120, Germany
| | - Remus T Dame
- Macromolecular Biochemistry, Leiden Institute of Chemistry, Leiden University, Leiden, 2333CC, The Netherlands.
- Centre for Microbial Cell Biology, Leiden University, Leiden, 2333CC, The Netherlands.
- Centre for Interdisciplinary Genome Research, Leiden University, Leiden, 2333CC, The Netherlands.
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18
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Uz-Zaman MH, D'Alton S, Barrick JE, Ochman H. Promoter capture drives the emergence of proto-genes in Escherichia coli. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.15.567300. [PMID: 38013999 PMCID: PMC10680751 DOI: 10.1101/2023.11.15.567300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
The phenomenon of de novo gene birth-the emergence of genes from non-genic sequences-has received considerable attention due to the widespread occurrence of genes that are unique to particular species or genomes. Most instances of de novo gene birth have been recognized through comparative analyses of genome sequences in eukaryotes, despite the abundance of novel, lineage-specific genes in bacteria and the relative ease with which bacteria can be studied in an experimental context. Here, we explore the genetic record of the Escherichia coli Long-Term Evolution Experiment (LTEE) for changes indicative of "proto-genic" phases of new gene birth in which non-genic sequences evolve stable transcription and/or translation. Over the time-span of the LTEE, non-genic regions are frequently transcribed, translated and differentially expressed, thereby serving as raw material for new gene emergence. Most proto-genes result either from insertion element activity or chromosomal translocations that fused pre-existing regulatory sequences to regions that were not expressed in the LTEE ancestor. Additionally, we identified instances of proto-gene emergence in which a previously unexpressed sequence was transcribed after formation of an upstream promoter. Tracing the origin of the causative mutations, we discovered that most occurred early in the history of the LTEE, often within the first 20,000 generations, and became fixed soon after emergence. Our findings show that proto-genes emerge frequently within evolving populations, persist stably, and can serve as potential substrates for new gene formation.
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19
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Zhao L, Ge T, Cheng T, Wang Q, Cui M, Yuan H, Zhao L. Fine-tuning gene expression of regulator AdmX for improved biosynthesis of andrimid in Erwinia persicina BST187. Appl Microbiol Biotechnol 2023; 107:6775-6788. [PMID: 37715803 DOI: 10.1007/s00253-023-12770-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 08/17/2023] [Accepted: 09/01/2023] [Indexed: 09/18/2023]
Abstract
Andrimid is a potent antibiotic that inhibits acetyl-CoA carboxylase. However, its low biological yield and complex chemical synthesis have hindered its large-scale application. In this study, we found that the LysR-type transcriptional activator AdmX controls andrimid yield by adjusting its expression level in the andrimid-producing bacterium Erwinia persicina strain BST187. Our results showed that gradually increasing of admX transcriptional levels significantly improved andrimid yield, while the yield declined when admX was overexpressed excessively. To further estimate the effect of AdmX on andrimid promotion, we fitted and developed a model which was y = -0.5576x2 + 61.945x + 800.63 (R2 = 0.9591), where x represents the admX transcriptional level and y represents andrimid yield. Andrimid yield of admX overexpression strain BST187ΔadmX/pET28a-Pgap-1::admX was greatly improved by 260%, which was reported for the first time that andrimid yield could be promoted by genetic engineering. Thus, this study provides important insights that the biosynthesis of andrimid would be improved by bioengineering and sheds lights on the potential application of andrimid in both biomedicine and bioagricultural manipulation with its large-scale production in the future. KEY POINTS: • Andrimid production can be greatly promoted by genetic engineering on non-model chassis. • The relationship between AdmX abundance and andrimid yield in Erwinia persicina strain BST187 might be parabolic. • Erwinia persicina BST187 combined with chassis modification enable the promising applications in andrimid industrialization.
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Affiliation(s)
- Lunqiang Zhao
- Key Laboratory of Engineering Biology for Low Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, China
- College of Biological Sciences, China Agricultural University, Beijing, China
| | - Tongling Ge
- Key Laboratory of Engineering Biology for Low Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, China
- National Center of Technology Innovation for Synthetic Biology, Tianjin, China
| | - Tingfeng Cheng
- Key Laboratory of Engineering Biology for Low Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, China
| | - Qing Wang
- Key Laboratory of Engineering Biology for Low Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, China
- National Center of Technology Innovation for Synthetic Biology, Tianjin, China
| | - Meijie Cui
- Key Laboratory of Engineering Biology for Low Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, China
| | - Hongli Yuan
- College of Biological Sciences, China Agricultural University, Beijing, China
| | - Lei Zhao
- Key Laboratory of Engineering Biology for Low Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, China.
- National Center of Technology Innovation for Synthetic Biology, Tianjin, China.
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20
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Bravo A, Moreno-Blanco A, Espinosa M. One Earth: The Equilibrium between the Human and the Bacterial Worlds. Int J Mol Sci 2023; 24:15047. [PMID: 37894729 PMCID: PMC10606248 DOI: 10.3390/ijms242015047] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/21/2023] [Accepted: 09/25/2023] [Indexed: 10/29/2023] Open
Abstract
Misuse and abuse of antibiotics on humans, cattle, and crops have led to the selection of multi-resistant pathogenic bacteria, the most feared 'superbugs'. Infections caused by superbugs are progressively difficult to treat, with a subsequent increase in lethality: the toll on human lives is predicted to reach 10 million by 2050. Here we review three concepts linked to the growing resistance to antibiotics, namely (i) the Resistome, which refers to the collection of bacterial genes that confer resistance to antibiotics, (ii) the Mobilome, which includes all the mobile genetic elements that participate in the spreading of antibiotic resistance among bacteria by horizontal gene transfer processes, and (iii) the Nichome, which refers to the set of genes that are expressed when bacteria try to colonize new niches. We also discuss the strategies that can be used to tackle bacterial infections and propose an entente cordiale with the bacterial world so that instead of war and destruction of the 'fierce enemy' we can achieve a peaceful coexistence (the One Earth concept) between the human and the bacterial worlds. This, in turn, will contribute to microbial biodiversity, which is crucial in a globally changing climate due to anthropogenic activities.
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Affiliation(s)
- Alicia Bravo
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas (CSIC), Ramiro de Maeztu 9, E-28040 Madrid, Spain
| | | | - Manuel Espinosa
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas (CSIC), Ramiro de Maeztu 9, E-28040 Madrid, Spain
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21
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Groisman EA, Choi J. Advancing evolution: Bacteria break down gene silencer to express horizontally acquired genes. Bioessays 2023; 45:e2300062. [PMID: 37533411 PMCID: PMC10530229 DOI: 10.1002/bies.202300062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 07/25/2023] [Accepted: 07/28/2023] [Indexed: 08/04/2023]
Abstract
Horizontal gene transfer advances bacterial evolution. To benefit from horizontally acquired genes, enteric bacteria must overcome silencing caused when the widespread heat-stable nucleoid structuring (H-NS) protein binds to AT-rich horizontally acquired genes. This ability had previously been ascribed to both anti-silencing proteins outcompeting H-NS for binding to AT-rich DNA and RNA polymerase initiating transcription from alternative promoters. However, we now know that pathogenic Salmonella enterica serovar Typhimurium and commensal Escherichia coli break down H-NS when this silencer is not bound to DNA. Curiously, both species use the same protease - Lon - to destroy H-NS in distinct environments. Anti-silencing proteins promote the expression of horizontally acquired genes without binding to them by displacing H-NS from AT-rich DNA, thus leaving H-NS susceptible to proteolysis and decreasing H-NS amounts overall. Conserved amino acid sequences in the Lon protease and H-NS cleavage site suggest that diverse bacteria degrade H-NS to exploit horizontally acquired genes.
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Affiliation(s)
- Eduardo A. Groisman
- Department of Microbial Pathogenesis, Yale School of Medicine, 295 Congress Avenue, New Haven, CT 06536, USA
- Yale Microbial Sciences Institute, P.O. Box 27389, West Haven, CT, 06516, USA
| | - Jeongjoon Choi
- Department of Genetics, Yale School of Medicine, 295 Congress Avenue, New Haven, CT 06536, USA
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22
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Rashid FZM, Dame RT. Three-dimensional chromosome re-modelling: The integral mechanism of transcription regulation in bacteria. Mol Microbiol 2023; 120:60-70. [PMID: 37433047 DOI: 10.1111/mmi.15062] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 03/28/2023] [Accepted: 03/29/2023] [Indexed: 07/13/2023]
Abstract
Nucleoid-associated proteins (NAPs) are architectural proteins of the bacterial chromosome and transcription factors that dynamically organise the chromosome and regulate gene expression in response to physicochemical environmental signals. While the architectural and regulatory functions of NAPs have been verified independently, the coupling between these functions in vivo has not been conclusively proven. Here we describe a model NAP - histone-like nucleoid structuring protein (H-NS) - as a coupled sensor-effector that directly regulates gene expression by chromatin re-modelling in response to physicochemical environmental signals. We outline how H-NS-binding partners and post-translational modifications modulate the role of H-NS as a transcription factor by influencing its DNA structuring properties. We consolidate our ideas in models of how H-NS may regulate the expression of the proVWX and hlyCABD operons by chromatin re-modelling. The interplay between chromosome structure and gene expression may be a common - but, at present, under-appreciated - concept of transcription regulation in bacteria.
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Affiliation(s)
- Fatema-Zahra M Rashid
- Macromolecular Biochemistry, Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
- Centre for Microbial Cell Biology, Leiden University, Leiden, The Netherlands
- Centre for Interdisciplinary Genome Research, Leiden University, Leiden, The Netherlands
| | - Remus T Dame
- Macromolecular Biochemistry, Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
- Centre for Microbial Cell Biology, Leiden University, Leiden, The Netherlands
- Centre for Interdisciplinary Genome Research, Leiden University, Leiden, The Netherlands
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23
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Fitzgerald DM, Stringer AM, Smith C, Lapierre P, Wade JT. Genome-Wide Mapping of the Escherichia coli PhoB Regulon Reveals Many Transcriptionally Inert, Intragenic Binding Sites. mBio 2023; 14:e0253522. [PMID: 37067422 PMCID: PMC10294691 DOI: 10.1128/mbio.02535-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 03/23/2023] [Indexed: 04/18/2023] Open
Abstract
Genome-scale analyses have revealed many transcription factor binding sites within, rather than upstream of, genes, raising questions as to the function of these binding sites. Here, we use complementary approaches to map the regulon of the Escherichia coli transcription factor PhoB, a response regulator that controls transcription of genes involved in phosphate homeostasis. Strikingly, the majority of PhoB binding sites are located within genes, but these intragenic sites are not associated with detectable transcription regulation and are not evolutionarily conserved. Many intragenic PhoB sites are located in regions bound by H-NS, likely due to shared sequence preferences of PhoB and H-NS. However, these PhoB binding sites are not associated with transcription regulation even in the absence of H-NS. We propose that for many transcription factors, including PhoB, binding sites not associated with promoter sequences are transcriptionally inert and hence are tolerated as genomic "noise." IMPORTANCE Recent studies have revealed large numbers of transcription factor binding sites within the genes of bacteria. The function, if any, of the vast majority of these binding sites has not been investigated. Here, we map the binding of the transcription factor PhoB across the Escherichia coli genome, revealing that the majority of PhoB binding sites are within genes. We show that PhoB binding sites within genes are not associated with regulation of the overlapping genes. Indeed, our data suggest that bacteria tolerate the presence of large numbers of nonregulatory, intragenic binding sites for transcription factors and that these binding sites are not under selective pressure.
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Affiliation(s)
- Devon M. Fitzgerald
- Wadsworth Center, New York State Department of Health, Albany, New York, USA
- Department of Biomedical Sciences, School of Public Health, University at Albany, Albany, New York, USA
| | - Anne M. Stringer
- Wadsworth Center, New York State Department of Health, Albany, New York, USA
| | - Carol Smith
- Wadsworth Center, New York State Department of Health, Albany, New York, USA
| | - Pascal Lapierre
- Wadsworth Center, New York State Department of Health, Albany, New York, USA
| | - Joseph T. Wade
- Wadsworth Center, New York State Department of Health, Albany, New York, USA
- Department of Biomedical Sciences, School of Public Health, University at Albany, Albany, New York, USA
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24
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Picker MA, Karney MMA, Gerson TM, Karabachev A, Duhart J, McKenna J, Wing H. Localized modulation of DNA supercoiling, triggered by the Shigella anti-silencer VirB, is sufficient to relieve H-NS-mediated silencing. Nucleic Acids Res 2023; 51:3679-3695. [PMID: 36794722 PMCID: PMC10164555 DOI: 10.1093/nar/gkad088] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 01/27/2023] [Accepted: 01/31/2023] [Indexed: 02/17/2023] Open
Abstract
In Bacteria, nucleoid structuring proteins govern nucleoid dynamics and regulate transcription. In Shigella spp., at ≤30°C, the histone-like nucleoid structuring protein (H-NS) transcriptionally silences many genes on the large virulence plasmid. Upon a switch to 37°C, VirB, a DNA binding protein and key transcriptional regulator of Shigella virulence, is produced. VirB functions to counter H-NS-mediated silencing in a process called transcriptional anti-silencing. Here, we show that VirB mediates a loss of negative DNA supercoils from our plasmid-borne, VirB-regulated PicsP-lacZ reporter in vivo. The changes are not caused by a VirB-dependent increase in transcription, nor do they require the presence of H-NS. Instead, the VirB-dependent change in DNA supercoiling requires the interaction of VirB with its DNA binding site, a critical first step in VirB-dependent gene regulation. Using two complementary approaches, we show that VirB:DNA interactions in vitro introduce positive supercoils in plasmid DNA. Subsequently, by exploiting transcription-coupled DNA supercoiling, we reveal that a localized loss of negative supercoils is sufficient to alleviate H-NS-mediated transcriptional silencing independently of VirB. Together, our findings provide novel insight into VirB, a central regulator of Shigella virulence and, more broadly, a molecular mechanism that offsets H-NS-dependent silencing of transcription in bacteria.
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Affiliation(s)
- Michael A Picker
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV 89154-4004, USA
| | - Monika M A Karney
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV 89154-4004, USA
| | - Taylor M Gerson
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV 89154-4004, USA
| | | | - Juan C Duhart
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV 89154-4004, USA
| | - Joy A McKenna
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV 89154-4004, USA
| | - Helen J Wing
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV 89154-4004, USA
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Middlemiss AD, Warman EA, Forrest D, Haycocks JRJ, Grainger DC. An unexpected abundance of bidirectional promoters within Salmonella Typhimurium plasmids. MICROBIOLOGY (READING, ENGLAND) 2023; 169:001339. [PMID: 37204130 PMCID: PMC10268837 DOI: 10.1099/mic.0.001339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 05/05/2023] [Indexed: 05/20/2023]
Abstract
Transcription of the DNA template, to generate an RNA message, is the first step in gene expression. The process initiates at DNA sequences called promoters. Conventionally, promoters have been considered to drive transcription in a specific direction. However, in recent work, we showed that many prokaryotic promoters can drive divergent transcription. This is a consequence of key DNA sequences for transcription initiation being inherently symmetrical. Here, we used global transcription start site mapping to determine the prevalence of such bidirectional promoters in Salmonella Typhimurium. Surprisingly, bidirectional promoters occur three times more frequently in plasmid components of the genome compared to chromosomal DNA. Implications for the evolution of promoter sequences are discussed.
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Affiliation(s)
| | - Emily A. Warman
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - David Forrest
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - James R. J. Haycocks
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - David C. Grainger
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
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Fitzgerald D, Stringer A, Smith C, Lapierre P, Wade JT. Genome-wide mapping of the Escherichia coli PhoB regulon reveals many transcriptionally inert, intragenic binding sites. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.07.527549. [PMID: 36798257 PMCID: PMC9934606 DOI: 10.1101/2023.02.07.527549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Genome-scale analyses have revealed many transcription factor binding sites within, rather than upstream of genes, raising questions as to the function of these binding sites. Here, we use complementary approaches to map the regulon of the Escherichia coli transcription factor PhoB, a response regulator that controls transcription of genes involved in phosphate homeostasis. Strikingly, the majority of PhoB binding sites are located within genes, but these intragenic sites are not associated with detectable transcription regulation and are not evolutionarily conserved. Many intragenic PhoB sites are located in regions bound by H-NS, likely due to shared sequence preferences of PhoB and H-NS. However, these PhoB binding sites are not associated with transcription regulation even in the absence of H-NS. We propose that for many transcription factors, including PhoB, binding sites not associated with promoter sequences are transcriptionally inert, and hence are tolerated as genomic "noise". IMPORTANCE Recent studies have revealed large numbers of transcription factor binding sites within the genes of bacteria. The function, if any, of the vast majority of these binding sites has not been investigated. Here, we map the binding of the transcription factor PhoB across the Escherichia coli genome, revealing that the majority of PhoB binding sites are within genes. We show that PhoB binding sites within genes are not associated with regulation of the overlapping genes. Indeed, our data suggest that bacteria tolerate the presence of large numbers of non-regulatory, intragenic binding sites for transcription factors, and that these binding sites are not under selective pressure.
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Affiliation(s)
- Devon Fitzgerald
- Wadsworth Center, New York State Department of Health, Albany, New York, USA
- Department of Biomedical Sciences, School of Public Health, University at Albany, Albany, New York, USA
| | - Anne Stringer
- Wadsworth Center, New York State Department of Health, Albany, New York, USA
| | - Carol Smith
- Wadsworth Center, New York State Department of Health, Albany, New York, USA
| | - Pascal Lapierre
- Wadsworth Center, New York State Department of Health, Albany, New York, USA
| | - Joseph T. Wade
- Wadsworth Center, New York State Department of Health, Albany, New York, USA
- Department of Biomedical Sciences, School of Public Health, University at Albany, Albany, New York, USA
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Picker MA, Karney MMA, Gerson TM, Karabachev AD, Duhart JC, McKenna JA, Wing HJ. Localized modulation of DNA supercoiling, triggered by the Shigella anti-silencer VirB, is sufficient to relieve H-NS-mediated silencing. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.09.523335. [PMID: 36711906 PMCID: PMC9882051 DOI: 10.1101/2023.01.09.523335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
In Bacteria, nucleoid structuring proteins govern nucleoid dynamics and regulate transcription. In Shigella spp ., at ≤ 30 °C, the histone-like nucleoid structuring protein (H-NS) transcriptionally silences many genes on the large virulence plasmid. Upon a switch to 37 °C, VirB, a DNA binding protein and key transcriptional regulator of Shigella virulence, is produced. VirB functions to counter H-NS-mediated silencing in a process called transcriptional anti-silencing. Here, we show that VirB mediates a loss of negative DNA supercoils from our plasmid-borne, VirB-regulated PicsP-lacZ reporter, in vivo . The changes are not caused by a VirB-dependent increase in transcription, nor do they require the presence of H-NS. Instead, the VirB-dependent change in DNA supercoiling requires the interaction of VirB with its DNA binding site, a critical first step in VirB-dependent gene regulation. Using two complementary approaches, we show that VirB:DNA interactions in vitro introduce positive supercoils in plasmid DNA. Subsequently, by exploiting transcription-coupled DNA supercoiling, we reveal that a localized loss of negative supercoils is sufficient to alleviate H-NS-mediated transcriptional silencing, independently of VirB. Together, our findings provide novel insight into VirB, a central regulator of Shigella virulence and more broadly, a molecular mechanism that offsets H-NS-dependent silencing of transcription in bacteria.
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Tutukina MN, Dakhnovets AI, Kaznadzey AD, Gelfand MS, Ozoline ON. Sense and antisense RNA products of the uxuR gene can affect motility and chemotaxis acting independent of the UxuR protein. Front Mol Biosci 2023; 10:1121376. [PMID: 36936992 PMCID: PMC10016265 DOI: 10.3389/fmolb.2023.1121376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Accepted: 02/06/2023] [Indexed: 02/19/2023] Open
Abstract
Small non-coding and antisense RNAs are widespread in all kingdoms of life, however, the diversity of their functions in bacteria is largely unknown. Here, we study RNAs synthesised from divergent promoters located in the 3'-end of the uxuR gene, encoding transcription factor regulating hexuronate metabolism in Escherichia coli. These overlapping promoters were predicted in silico with rather high scores, effectively bound RNA polymerase in vitro and in vivo and were capable of initiating transcription in sense and antisense directions. The genome-wide correlation between in silico promoter scores and RNA polymerase binding in vitro and in vivo was higher for promoters located on the antisense strands of the genes, however, sense promoters within the uxuR gene were more active. Both regulatory RNAs synthesised from the divergent promoters inhibited expression of genes associated with the E. coli motility and chemotaxis independent of a carbon source on which bacteria had been grown. Direct effects of these RNAs were confirmed for the fliA gene encoding σ28 subunit of RNA polymerase. In addition to intracellular sRNAs, promoters located within the uxuR gene could initiate synthesis of transcripts found in the fraction of RNAs secreted in the extracellular medium. Their profile was also carbon-independent suggesting that intragenic uxuR transcripts have a specific regulatory role not directly related to the function of the protein in which gene they are encoded.
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Affiliation(s)
- Maria N. Tutukina
- Center for Molecular and Cellular Biology, Skolkovo Institute of Science and Technology, Moscow, Russia
- Lab of Functional Genomics and Cellular Stress, Institute of Cell Biophysics RAS, FRC PRCBR, Pushchino, Russia
- RTC “Bioinformatics”, A. A. Kharkevich Institute for Information Transmission Problems RAS, Moscow, Russia
- *Correspondence: Maria N. Tutukina, , Olga N. Ozoline,
| | - Artemiy I. Dakhnovets
- Center for Molecular and Cellular Biology, Skolkovo Institute of Science and Technology, Moscow, Russia
- Department of Biotechnology, M. V. Lomonosov Moscow State University, Moscow, Russia
| | - Anna D. Kaznadzey
- RTC “Bioinformatics”, A. A. Kharkevich Institute for Information Transmission Problems RAS, Moscow, Russia
| | - Mikhail S. Gelfand
- Center for Molecular and Cellular Biology, Skolkovo Institute of Science and Technology, Moscow, Russia
- RTC “Bioinformatics”, A. A. Kharkevich Institute for Information Transmission Problems RAS, Moscow, Russia
| | - Olga N. Ozoline
- Lab of Functional Genomics and Cellular Stress, Institute of Cell Biophysics RAS, FRC PRCBR, Pushchino, Russia
- *Correspondence: Maria N. Tutukina, , Olga N. Ozoline,
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RfaH Counter-Silences Inhibition of Transcript Elongation by H-NS-StpA Nucleoprotein Filaments in Pathogenic Escherichia coli. mBio 2022; 13:e0266222. [PMID: 36264101 PMCID: PMC9765446 DOI: 10.1128/mbio.02662-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Expression of virulence genes in pathogenic Escherichia coli is controlled in part by the transcription silencer H-NS and its paralogs (e.g., StpA), which sequester DNA in multi-kb nucleoprotein filaments to inhibit transcription initiation, elongation, or both. Some activators counter-silence initiation by displacing H-NS from promoters, but how H-NS inhibition of elongation is overcome is not understood. In uropathogenic E. coli (UPEC), elongation regulator RfaH aids expression of some H-NS-silenced pathogenicity operons (e.g., hlyCABD encoding hemolysin). RfaH associates with elongation complexes (ECs) via direct contacts to a transiently exposed, nontemplate DNA strand sequence called operon polarity suppressor (ops). RfaH-ops interactions establish long-lived RfaH-EC contacts that allow RfaH to recruit ribosomes to the nascent mRNA and to suppress transcriptional pausing and termination. Using ChIP-seq, we mapped the genome-scale distributions of RfaH, H-NS, StpA, RNA polymerase (RNAP), and σ70 in the UPEC strain CFT073. We identify eight RfaH-activated operons, all of which were bound by H-NS and StpA. Four are new additions to the RfaH regulon. Deletion of RfaH caused premature termination, whereas deletion of H-NS and StpA allowed elongation without RfaH. Thus, RfaH is an elongation counter-silencer of H-NS. Consistent with elongation counter-silencing, deletion of StpA alone decreased the effect of RfaH. StpA increases DNA bridging, which inhibits transcript elongation via topological constraints on RNAP. Residual RfaH effect when both H-NS and StpA were deleted was attributable to targeting of RfaH-regulated operons by a minor H-NS paralog, Hfp. These operons have evolved higher levels of H-NS-binding features, explaining minor-paralog targeting. IMPORTANCE Bacterial pathogens adapt to hosts and host defenses by reprogramming gene expression, including by H-NS counter-silencing. Counter-silencing turns on transcription initiation when regulators bind to promoters and rearrange repressive H-NS nucleoprotein filaments that ordinarily block transcription. The specialized NusG paralog RfaH also reprograms virulence genes but regulates transcription elongation. To understand how elongation regulators might affect genes silenced by H-NS, we mapped H-NS, StpA (an H-NS paralog), RfaH, σ70, and RNA polymerase (RNAP) locations on DNA in the uropathogenic E. coli strain CFT073. Although H-NS-StpA filaments bind only 18% of the CFT073 genome, all loci at which RfaH binds RNAP are also bound by H-NS-StpA and are silenced when RfaH is absent. Thus, RfaH represents a distinct class of counter-silencer that acts on elongating RNAP to enable transcription through repressive nucleoprotein filaments. Our findings define a new mechanism of elongation counter-silencing and explain how RfaH functions as a virulence regulator.
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Jing Kay Lam K, Zhang Z, Saier Jr MH. Histone-like Nucleoid Structuring (H-NS) Protein Silences the beta-glucoside (bgl) Utilization Operon in Escherichia coli by Forming a DNA Loop. Comput Struct Biotechnol J 2022; 20:6287-6301. [DOI: 10.1016/j.csbj.2022.11.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 11/10/2022] [Accepted: 11/10/2022] [Indexed: 11/15/2022] Open
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Figueroa-Bossi N, Sánchez-Romero MA, Kerboriou P, Naquin D, Mendes C, Bouloc P, Casadesús J, Bossi L. Pervasive transcription enhances the accessibility of H-NS-silenced promoters and generates bistability in Salmonella virulence gene expression. Proc Natl Acad Sci U S A 2022; 119:e2203011119. [PMID: 35858437 PMCID: PMC9335307 DOI: 10.1073/pnas.2203011119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 06/01/2022] [Indexed: 01/21/2023] Open
Abstract
In Escherichia coli and Salmonella, many genes silenced by the nucleoid structuring protein H-NS are activated upon inhibiting Rho-dependent transcription termination. This response is poorly understood and difficult to reconcile with the view that H-NS acts mainly by blocking transcription initiation. Here we have analyzed the basis for the up-regulation of H-NS-silenced Salmonella pathogenicity island 1 (SPI-1) in cells depleted of Rho-cofactor NusG. Evidence from genetic experiments, semiquantitative 5' rapid amplification of complementary DNA ends sequencing (5' RACE-Seq), and chromatin immunoprecipitation sequencing (ChIP-Seq) shows that transcription originating from spurious antisense promoters, when not stopped by Rho, elongates into a H-NS-bound regulatory region of SPI-1, displacing H-NS and rendering the DNA accessible to the master regulator HilD. In turn, HilD's ability to activate its own transcription triggers a positive feedback loop that results in transcriptional activation of the entire SPI-1. Significantly, single-cell analyses revealed that this mechanism is largely responsible for the coexistence of two subpopulations of cells that either express or do not express SPI-1 genes. We propose that cell-to-cell differences produced by stochastic spurious transcription, combined with feedback loops that perpetuate the activated state, can generate bimodal gene expression patterns in bacterial populations.
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Affiliation(s)
- Nara Figueroa-Bossi
- Université Paris-Saclay, CEA, CNRS, Institut de Biologie Intégrative de la Cellule (I2BC), 91190 Gif-sur-Yvette, France
| | - María Antonia Sánchez-Romero
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad de Sevilla, 41012 Sevilla, Spain
| | - Patricia Kerboriou
- Université Paris-Saclay, CEA, CNRS, Institut de Biologie Intégrative de la Cellule (I2BC), 91190 Gif-sur-Yvette, France
| | - Delphine Naquin
- Université Paris-Saclay, CEA, CNRS, Institut de Biologie Intégrative de la Cellule (I2BC), 91190 Gif-sur-Yvette, France
| | - Clara Mendes
- Université Paris-Saclay, CEA, CNRS, Institut de Biologie Intégrative de la Cellule (I2BC), 91190 Gif-sur-Yvette, France
| | - Philippe Bouloc
- Université Paris-Saclay, CEA, CNRS, Institut de Biologie Intégrative de la Cellule (I2BC), 91190 Gif-sur-Yvette, France
| | - Josep Casadesús
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Sevilla, Spain
| | - Lionello Bossi
- Université Paris-Saclay, CEA, CNRS, Institut de Biologie Intégrative de la Cellule (I2BC), 91190 Gif-sur-Yvette, France
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Ha T, DiPrima M, Koparde V, Jailwala P, Ohnuki H, Feng JX, Palangat M, Larson D, Tosato G. Antisense transcription from lentiviral gene targeting linked to an integrated stress response in colorectal cancer cells. MOLECULAR THERAPY - NUCLEIC ACIDS 2022; 28:877-891. [PMID: 35694213 PMCID: PMC9163427 DOI: 10.1016/j.omtn.2022.05.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 05/12/2022] [Indexed: 11/10/2022]
Abstract
Advances in gene therapy research have resulted in the successful development of new therapies for clinical use. Here, we explored a gene targeting approach to deplete ephrinB2 from colorectal cancer cells using an inducible lentiviral vector. EphrinB2, a transmembrane ephrin ligand, promotes colorectal cancer cell growth and viability and predicts poor patient survival when expressed at high levels in colorectal cancer tissues. We discovered that lentiviral vector integration and expression in the host DNA frequently drive divergent host gene transcription, generating antisense reads coupled with splicing events and generation of chimeric vector/host transcripts. Antisense transcription of host DNA was linked to development of an integrated stress response and cell death. Despite recent successes, off-target effects remain a concern in genetic medicine. Our results provide evidence that divergent gene transcription is a previously unrecognized off-target effect of lentiviral vector integration with built-in properties for regulation of gene expression.
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Aldawood E, Roberts IS. Regulation of Escherichia coli Group 2 Capsule Gene Expression: A Mini Review and Update. Front Microbiol 2022; 13:858767. [PMID: 35359738 PMCID: PMC8960920 DOI: 10.3389/fmicb.2022.858767] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 02/21/2022] [Indexed: 11/22/2022] Open
Abstract
The expression of a group 2 capsule (K antigen), such as the K1 or K5 antigen, is a key virulence factor of Escherichia coli responsible for extra-intestinal infections. Capsule expression confers resistance to innate host defenses and plays a critical role in invasive disease. Capsule expression is temperature-dependent being expressed at 37°C but not at 20°C when outside the host. Group 2 capsule gene expression involves two convergent promoters PR1 and PR3, the regulation of which is critical to capsule expression. Temperature-dependent expression is controlled at transcriptional level directly by the binding of H-NS to PR1 and PR3 and indirectly through BipA with additional input from IHF and SlyA. More recently, other regulatory proteins, FNR, Fur, IHF, MprA, and LrhA, have been implicated in regulating capsule gene expression in response to other environmental stimuli and there is merging data for the growth phase-dependent regulation of the PR1 and PR3 promoters. The aim of the present Mini Review is to provide a unified update on the latest data on how the expression of group 2 capsules is regulated in response to a number of stimuli and the growth phase something that has not to date been addressed.
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Affiliation(s)
- Esraa Aldawood
- School of Biological Sciences, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
- Clinical Laboratory Science, Collage of Applied Medical Science, King Saud University, Riyadh, Saudi Arabia
| | - Ian S. Roberts
- School of Biological Sciences, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
- *Correspondence: Ian S. Roberts,
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Forrest D, Warman EA, Erkelens AM, Dame RT, Grainger DC. Xenogeneic silencing strategies in bacteria are dictated by RNA polymerase promiscuity. Nat Commun 2022; 13:1149. [PMID: 35241653 PMCID: PMC8894471 DOI: 10.1038/s41467-022-28747-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 02/07/2022] [Indexed: 12/13/2022] Open
Abstract
Horizontal gene transfer facilitates dissemination of favourable traits among bacteria. However, foreign DNA can also reduce host fitness: incoming sequences with a higher AT content than the host genome can misdirect transcription. Xenogeneic silencing proteins counteract this by modulating RNA polymerase binding. In this work, we compare xenogeneic silencing strategies of two distantly related model organisms: Escherichia coli and Bacillus subtilis. In E. coli, silencing is mediated by the H-NS protein that binds extensively across horizontally acquired genes. This prevents spurious non-coding transcription, mostly intragenic in origin. By contrast, binding of the B. subtilis Rok protein is more targeted and mostly silences expression of functional mRNAs. The difference reflects contrasting transcriptional promiscuity in E. coli and B. subtilis, largely attributable to housekeeping RNA polymerase σ factors. Thus, whilst RNA polymerase specificity is key to the xenogeneic silencing strategy of B. subtilis, transcriptional promiscuity must be overcome to silence horizontally acquired DNA in E. coli. Bacteria use specific silencing proteins to prevent spurious transcription of horizontally acquired DNA. Here, Forrest et al. describe differences in silencing strategies between E. coli and Bacillus subtilis, driven by the respective specificities of the silencing protein and the RNA polymerase in each organism.
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Affiliation(s)
- David Forrest
- School of Biosciences, University of Birmingham, Edgbaston, B15 2TT, UK
| | - Emily A Warman
- School of Biosciences, University of Birmingham, Edgbaston, B15 2TT, UK
| | - Amanda M Erkelens
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333CC, Leiden, The Netherlands
| | - Remus T Dame
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333CC, Leiden, The Netherlands.,Centre for Microbial Cell Biology, Leiden University, Einsteinweg 55, 2333CC, Leiden, The Netherlands
| | - David C Grainger
- School of Biosciences, University of Birmingham, Edgbaston, B15 2TT, UK.
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35
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Amemiya HM, Goss TJ, Nye TM, Hurto RL, Simmons LA, Freddolino PL. Distinct heterochromatin-like domains promote transcriptional memory and silence parasitic genetic elements in bacteria. EMBO J 2022; 41:e108708. [PMID: 34961960 PMCID: PMC8804932 DOI: 10.15252/embj.2021108708] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 11/22/2021] [Accepted: 11/29/2021] [Indexed: 02/03/2023] Open
Abstract
There is increasing evidence that prokaryotes maintain chromosome structure, which in turn impacts gene expression. We recently characterized densely occupied, multi-kilobase regions in the E. coli genome that are transcriptionally silent, similar to eukaryotic heterochromatin. These extended protein occupancy domains (EPODs) span genomic regions containing genes encoding metabolic pathways as well as parasitic elements such as prophages. Here, we investigate the contributions of nucleoid-associated proteins (NAPs) to the structuring of these domains, by examining the impacts of deleting NAPs on EPODs genome-wide in E. coli and B. subtilis. We identify key NAPs contributing to the silencing of specific EPODs, whose deletion opens a chromosomal region for RNA polymerase binding at genes contained within that region. We show that changes in E. coli EPODs facilitate an extra layer of transcriptional regulation, which prepares cells for exposure to exotic carbon sources. Furthermore, we distinguish novel xenogeneic silencing roles for the NAPs Fis and Hfq, with the presence of at least one being essential for cell viability in the presence of domesticated prophages. Our findings reveal previously unrecognized mechanisms through which genomic architecture primes bacteria for changing metabolic environments and silences harmful genomic elements.
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Affiliation(s)
- Haley M Amemiya
- Cellular and Molecular Biology ProgramUniversity of Michigan Medical SchoolAnn ArborMIUSA
- Department of Computational Medicine and BioinformaticsUniversity of Michigan Medical SchoolAnn ArborMIUSA
- Present address:
Broad Institute of MIT and HarvardCambridgeMAUSA
| | - Thomas J Goss
- Department of Biological ChemistryUniversity of Michigan Medical SchoolAnn ArborMIUSA
| | - Taylor M Nye
- Department of Molecular, Cellular, and Developmental BiologyUniversity of MichiganAnn ArborMIUSA
- Present address:
Department of Molecular MicrobiologyWashington University in St. Louis School of MedicineSt. LouisMOUSA
| | - Rebecca L Hurto
- Department of Biological ChemistryUniversity of Michigan Medical SchoolAnn ArborMIUSA
| | - Lyle A Simmons
- Department of Molecular, Cellular, and Developmental BiologyUniversity of MichiganAnn ArborMIUSA
| | - Peter L Freddolino
- Cellular and Molecular Biology ProgramUniversity of Michigan Medical SchoolAnn ArborMIUSA
- Department of Computational Medicine and BioinformaticsUniversity of Michigan Medical SchoolAnn ArborMIUSA
- Department of Biological ChemistryUniversity of Michigan Medical SchoolAnn ArborMIUSA
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36
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Lato DF, Zeng Q, Golding GB. Genomic inversions in Escherichia coli alter gene expression and are associated with nucleoid protein binding sites. Genome 2022; 65:287-299. [DOI: 10.1139/gen-2021-0102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Genomic reorganization, like rearrangements and inversions, influence how genetic information is organized within bacterial genomes. Inversions in particular, facilitate genome evolution through gene gain and loss, and can alter gene expression. Previous studies investigating the impact inversions have on gene expression induced inversions targeting specific genes or examine inversions between distantly related species. This fails to encompass a genome wide perspective on naturally occurring inversions and their post adaptation impact on gene expression. Here we use bioinformatic techniques and multiple RNA-seq datasets to investigate the short- and long-range impact inversions have on genomic gene expression within <i>Escherichia coli</i>. We observed differences in gene expression between homologous inverted and non-inverted genes, even after long term exposure to adaptive selection. In 4% of inversions representing 33 genes, differential gene expression between inverted and non-inverted homologs was detected, with nearly two thirds (71%) of differentially expressed inverted genes having 9.4-85.6 fold higher gene expression. The identified inversions had more overlap than expected with nucleoid associated protein binding sites, which assist in genomic gene expression regulation. Some inversions can drastically impact gene expression even between different strains of <i>E.coli</i>, and could provide a mechanism for the diversification of genetic content through controlled expression changes.
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Affiliation(s)
| | - Qing Zeng
- McMaster University, Department of Biology, Hamilton, Ontario, Canada,
| | - G. Brian Golding
- McMaster University, Department of Biology, 1280 Main Street West, Hamilton, Ontario, Canada, L8S 4K1,
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37
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H-NS and ToxT Inversely Control Cholera Toxin Production by Binding to Overlapping DNA Sequences. J Bacteriol 2021; 203:e0018721. [PMID: 34228499 DOI: 10.1128/jb.00187-21] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Vibrio cholerae infects human hosts following ingestion of contaminated food or water, resulting in the severe diarrheal disease cholera. The watery diarrhea that is characteristic of the disease is directly caused by the production of cholera toxin (CT). A complex regulatory cascade controls the production of CT and other virulence factors. However, ultimately, a single protein, ToxT, directly binds to virulence gene promoters and activates their transcription. Previously, we identified two ToxT binding sites, or toxboxes, within the cholera toxin promoter (PctxAB). The toxboxes overlap the two promoter-proximal GATTTTT heptad repeats found within PctxAB in classical biotype V. cholerae strain O395. These heptad repeats were previously found to be located within a large DNA region bound by H-NS, a global transcriptional repressor present in Gram-negative bacteria. The current model for the control of PctxAB transcription proposes complete H-NS displacement from the DNA by ToxT, followed by direct activation by ToxT-RNA polymerase (RNAP) contacts. The goal of this study was to determine more precisely where H-NS binds to PctxAB and test the hypothesis that ToxT completely displaces H-NS from the PctxAB promoter before activating transcription. The results suggest that H-NS binds only to the region of PctxAB encompassing the heptad repeats and that ToxT displaces H-NS only from its most promoter-proximal binding sites, calling for a revision of the current model involving H-NS and ToxT at PctxAB. IMPORTANCE H-NS is a global negative regulator of transcription in Gram-negative bacteria, particularly in horizontally acquired genetic islands. Previous work in Vibrio cholerae suggested that H-NS represses the transcription of cholera toxin genes by binding to a large region upstream of its promoter and that the virulence activator ToxT derepresses transcription by removing H-NS from the promoter. Here, new data support a revised model in which ToxT displaces only H-NS bound to the most promoter-proximal DNA sites that overlap the ToxT binding sites, leaving the upstream sites occupied by H-NS. This introduces a higher-resolution mechanism for the antirepression of H-NS in the control of cholera toxin production.
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38
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Ishihama A, Shimada T. Hierarchy of transcription factor network in Escherichia coli K-12: H-NS-mediated silencing and Anti-silencing by global regulators. FEMS Microbiol Rev 2021; 45:6312496. [PMID: 34196371 DOI: 10.1093/femsre/fuab032] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 06/15/2021] [Indexed: 12/13/2022] Open
Abstract
Transcriptional regulation for genome expression determines growth and adaptation of single-cell bacteria that are directly exposed to environment. The transcriptional apparatus in Escherichia coli K-12 is composed of RNA polymerase core enzyme and two groups of its regulatory proteins, seven species of promoter-recognition subunit sigma and about 300 species of transcription factors. The identification of regulatory targets for all these regulatory proteins is critical toward understanding the genome regulation as a whole. For this purpose, we performed a systematic search in vitro of the whole set of binding sites for each factor by gSELEX system. This review summarizes the accumulated knowledge of regulatory targets for more than 150 TFs from E. coli K-12. Overall TFs could be classified into four families: nucleoid-associated bifunctional TFs; global regulators; local regulators; and single-target regulators, in which the regulatory functions remain uncharacterized for the nucleoid-associated TFs. Here we overview the regulatory targets of two nucleoid-associated TFs, H-NS and its paralog StpA, both together playing the silencing role of a set of non-essential genes. Participation of LeuO and other global regulators have been indicated for the anti-silencing. Finally, we propose the hierarchy of TF network as a key framework of the bacterial genome regulation.
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Affiliation(s)
- Akira Ishihama
- Hosei University, Research Institute for Micro-Nano Technology, Koganei, Tokyo 184-0003, Japan
| | - Tomohiro Shimada
- Meiji University, School of Agriculture, Kawasaki, Kanagawa 214-8571, Japan
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39
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Freddolino PL, Amemiya HM, Goss TJ, Tavazoie S. Dynamic landscape of protein occupancy across the Escherichia coli chromosome. PLoS Biol 2021; 19:e3001306. [PMID: 34170902 PMCID: PMC8282354 DOI: 10.1371/journal.pbio.3001306] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 07/15/2021] [Accepted: 06/02/2021] [Indexed: 12/18/2022] Open
Abstract
Free-living bacteria adapt to environmental change by reprogramming gene expression through precise interactions of hundreds of DNA-binding proteins. A predictive understanding of bacterial physiology requires us to globally monitor all such protein-DNA interactions across a range of environmental and genetic perturbations. Here, we show that such global observations are possible using an optimized version of in vivo protein occupancy display technology (in vivo protein occupancy display-high resolution, IPOD-HR) and present a pilot application to Escherichia coli. We observe that the E. coli protein-DNA interactome organizes into 2 distinct prototypic features: (1) highly dynamic condition-dependent transcription factor (TF) occupancy; and (2) robust kilobase scale occupancy by nucleoid factors, forming silencing domains analogous to eukaryotic heterochromatin. We show that occupancy dynamics across a range of conditions can rapidly reveal the global transcriptional regulatory organization of a bacterium. Beyond discovery of previously hidden regulatory logic, we show that these observations can be utilized to computationally determine sequence specificity models for the majority of active TFs. Our study demonstrates that global observations of protein occupancy combined with statistical inference can rapidly and systematically reveal the transcriptional regulatory and structural features of a bacterial genome. This capacity is particularly crucial for non-model bacteria that are not amenable to routine genetic manipulation.
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Affiliation(s)
- Peter L. Freddolino
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Haley M. Amemiya
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
- Cellular and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Thomas J. Goss
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Saeed Tavazoie
- Department of Biological Sciences, Columbia University, New York, New York, United States of America
- Department of Systems Biology, Columbia University, New York, New York, United States of America
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York, United States of America
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40
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Widespread divergent transcription from bacterial and archaeal promoters is a consequence of DNA-sequence symmetry. Nat Microbiol 2021; 6:746-756. [PMID: 33958766 PMCID: PMC7612053 DOI: 10.1038/s41564-021-00898-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 03/25/2021] [Indexed: 02/03/2023]
Abstract
Transcription initiates at promoters, DNA regions recognized by a DNA-dependent RNA polymerase. We previously identified horizontally acquired Escherichia coli promoters from which the direction of transcription was unclear. In the present study, we show that more than half of these promoters are bidirectional and drive divergent transcription. Using genome-scale approaches, we demonstrate that 19% of all transcription start sites detected in E. coli are associated with a bidirectional promoter. Bidirectional promoters are similarly common in diverse bacteria and archaea, and have inherent symmetry: specific bases required for transcription initiation are reciprocally co-located on opposite DNA strands. Bidirectional promoters enable co-regulation of divergent genes and are enriched in both intergenic and horizontally acquired regions. Divergent transcription is conserved among bacteria, archaea and eukaryotes, but the underlying mechanisms for bidirectionality are different.
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41
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Sadeh R, Sharkia I, Fialkoff G, Rahat A, Gutin J, Chappleboim A, Nitzan M, Fox-Fisher I, Neiman D, Meler G, Kamari Z, Yaish D, Peretz T, Hubert A, Cohen JE, Salah A, Temper M, Grinshpun A, Maoz M, Abu-Gazala S, Ya’acov AB, Shteyer E, Safadi R, Kaplan T, Shemer R, Planer D, Galun E, Glaser B, Zick A, Dor Y, Friedman N. ChIP-seq of plasma cell-free nucleosomes identifies gene expression programs of the cells of origin. Nat Biotechnol 2021; 39:586-598. [PMID: 33432199 PMCID: PMC7610786 DOI: 10.1038/s41587-020-00775-6] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 11/17/2020] [Indexed: 01/29/2023]
Abstract
Cell-free DNA (cfDNA) in human plasma provides access to molecular information about the pathological processes in the organs or tumors from which it originates. These DNA fragments are derived from fragmented chromatin in dying cells and retain some of the cell-of-origin histone modifications. In this study, we applied chromatin immunoprecipitation of cell-free nucleosomes carrying active chromatin modifications followed by sequencing (cfChIP-seq) to 268 human samples. In healthy donors, we identified bone marrow megakaryocytes, but not erythroblasts, as major contributors to the cfDNA pool. In patients with a range of liver diseases, we showed that we can identify pathology-related changes in hepatocyte transcriptional programs. In patients with metastatic colorectal carcinoma, we detected clinically relevant and patient-specific information, including transcriptionally active human epidermal growth factor receptor 2 (HER2) amplifications. Altogether, cfChIP-seq, using low sequencing depth, provides systemic and genome-wide information and can inform diagnosis and facilitate interrogation of physiological and pathological processes using blood samples.
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Affiliation(s)
- Ronen Sadeh
- The Rachel and Selim Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel,The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Israa Sharkia
- The Rachel and Selim Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel,The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Gavriel Fialkoff
- The Rachel and Selim Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel,The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Ayelet Rahat
- The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Jenia Gutin
- The Rachel and Selim Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel,The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Alon Chappleboim
- The Rachel and Selim Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel,The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Mor Nitzan
- The Rachel and Selim Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Ilana Fox-Fisher
- Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Daniel Neiman
- Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Guy Meler
- The Rachel and Selim Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Zahala Kamari
- The Rachel and Selim Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel,The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Dayana Yaish
- The Goldyne Savad Institute for Gene Therapy, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Tamar Peretz
- Sharett Institute of Oncology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Ayala Hubert
- Sharett Institute of Oncology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Jonathan E Cohen
- Sharett Institute of Oncology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel,The Wohl institute for Translational Medicine, Hadassah Medical Center
| | - Azzam Salah
- Sharett Institute of Oncology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Mark Temper
- Sharett Institute of Oncology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Albert Grinshpun
- Sharett Institute of Oncology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Myriam Maoz
- Sharett Institute of Oncology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Samir Abu-Gazala
- Department of Surgery, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Ami Ben Ya’acov
- The Juliet Keidan Institute of Pediatric Gastroenterology Institute, Shaare Zedek Medical Center, Jerusalem, Israel
| | - Eyal Shteyer
- The Juliet Keidan Institute of Pediatric Gastroenterology Institute, Shaare Zedek Medical Center, Jerusalem, Israel
| | - Rifaat Safadi
- The Liver Unit, Institute of Gastroenterology and Liver Diseases, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Tommy Kaplan
- The Rachel and Selim Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Ruth Shemer
- Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - David Planer
- Department of Cardiology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Eithan Galun
- The Goldyne Savad Institute for Gene Therapy, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Benjamin Glaser
- Dept of Endocrinology and Metabolism Service, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Aviad Zick
- Sharett Institute of Oncology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Yuval Dor
- Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Nir Friedman
- The Rachel and Selim Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel,The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel,lead contact:
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42
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Nascent RNA sequencing identifies a widespread sigma70-dependent pausing regulated by Gre factors in bacteria. Nat Commun 2021; 12:906. [PMID: 33568644 PMCID: PMC7876045 DOI: 10.1038/s41467-021-21150-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 01/14/2021] [Indexed: 01/29/2023] Open
Abstract
Promoter-proximal pausing regulates eukaryotic gene expression and serves as checkpoints to assemble elongation/splicing machinery. Little is known how broadly this type of pausing regulates transcription in bacteria. We apply nascent elongating transcript sequencing combined with RNase I footprinting for genome-wide analysis of σ70-dependent transcription pauses in Escherichia coli. Retention of σ70 induces strong backtracked pauses at a 10−20-bp distance from many promoters. The pauses in the 10−15-bp register of the promoter are dictated by the canonical −10 element, 6−7 nt spacer and “YR+1Y” motif centered at the transcription start site. The promoters for the pauses in the 16−20-bp register contain an additional −10-like sequence recognized by σ70. Our in vitro analysis reveals that DNA scrunching is involved in these pauses relieved by Gre cleavage factors. The genes coding for transcription factors are enriched in these pauses, suggesting that σ70 and Gre proteins regulate transcription in response to changing environmental cues. Transcription by bacterial RNA polymerase is interrupted by pausing events that play diverse regulatory roles. Here, the authors find that a large number of E. coli sigma70-dependent pauses, clustered at a 10−20-bp distance from promoters, are regulated by Gre cleavage factors constituting a mechanism for rapid response to changing environmental cues.
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43
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Genome-wide Identification of DNA-protein Interaction to Reconstruct Bacterial Transcription Regulatory Network. BIOTECHNOL BIOPROC E 2020. [DOI: 10.1007/s12257-020-0030-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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44
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Lippa AM, Gebhardt MJ, Dove SL. H-NS-like proteins in Pseudomonas aeruginosa coordinately silence intragenic transcription. Mol Microbiol 2020; 115:1138-1151. [PMID: 33245158 DOI: 10.1111/mmi.14656] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Revised: 11/22/2020] [Accepted: 11/23/2020] [Indexed: 01/22/2023]
Abstract
The H-NS-like proteins MvaT and MvaU act coordinately as global repressors in Pseudomonas aeruginosa by binding to AT-rich regions of the chromosome. Although cells can tolerate loss of either protein, identifying their combined regulatory effects has been challenging because the loss of both proteins is lethal due to induction of prophage Pf4 and subsequent superinfection of the cell. In other bacteria, H-NS promotes the cellular fitness by inhibiting intragenic transcription from AT-rich target regions, preventing them from sequestering RNA polymerase; however, it is not known whether MvaT and MvaU function similarly. Here, we utilize a parental strain that cannot be infected by Pf4 phage to define the collective MvaT and MvaU regulon and demonstrate that the combined loss of both MvaT and MvaU leads to increased intragenic transcription from loci directly controlled by these proteins. We further show that the loss of MvaT and MvaU leads to a striking redistribution of RNA polymerase containing σ70 to genomic regions vacated by these proteins. Our findings suggest that the ability of H-NS-like proteins to repress intragenic transcription is a universal function of these proteins and point to a second mechanism by which MvaT and MvaU may contribute to the growth of P. aeruginosa.
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Affiliation(s)
- Andrew M Lippa
- Division of Infectious Diseases, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Michael J Gebhardt
- Division of Infectious Diseases, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Simon L Dove
- Division of Infectious Diseases, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
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45
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Fitzgerald S, Kary SC, Alshabib EY, MacKenzie KD, Stoebel D, Chao TC, Cameron ADS. Redefining the H-NS protein family: a diversity of specialized core and accessory forms exhibit hierarchical transcriptional network integration. Nucleic Acids Res 2020; 48:10184-10198. [PMID: 32894292 PMCID: PMC7544231 DOI: 10.1093/nar/gkaa709] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 08/07/2020] [Accepted: 08/23/2020] [Indexed: 12/27/2022] Open
Abstract
H-NS is a nucleoid structuring protein and global repressor of virulence and horizontally-acquired genes in bacteria. H-NS can interact with itself or with homologous proteins, but protein family diversity and regulatory network overlap remain poorly defined. Here, we present a comprehensive phylogenetic analysis that revealed deep-branching clades, dispelling the presumption that H-NS is the progenitor of varied molecular backups. Each clade is composed exclusively of either chromosome-encoded or plasmid-encoded proteins. On chromosomes, stpA and newly discovered hlpP are core genes in specific genera, whereas hfp and newly discovered hlpC are sporadically distributed. Six clades of H-NS plasmid proteins (Hpp) exhibit ancient and dedicated associations with plasmids, including three clades with fidelity for plasmid incompatibility groups H, F or X. A proliferation of H-NS homologs in Erwiniaceae includes the first observation of potentially co-dependent H-NS forms. Conversely, the observed diversification of oligomerization domains may facilitate stable co-existence of divergent homologs in a genome. Transcriptomic and proteomic analysis in Salmonella revealed regulatory crosstalk and hierarchical control of H-NS homologs. We also discovered that H-NS is both a repressor and activator of Salmonella Pathogenicity Island 1 gene expression, and both regulatory modes are restored by Sfh (HppH) in the absence of H-NS.
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Affiliation(s)
- Stephen Fitzgerald
- Department of Biology, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
- Division of Immunity and Infection, The Roslin Institute and R(D)SVS, University of Edinburgh, Edinburgh EH25 9RG, UK
| | - Stefani C Kary
- Department of Biology, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Ebtihal Y Alshabib
- Department of Biology, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
- Institute for Microbial Systems and Society, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Keith D MacKenzie
- Department of Biology, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
- Institute for Microbial Systems and Society, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Daniel M Stoebel
- Department of Biology, Harvey Mudd College, Claremont, CA 91711, USA
| | - Tzu-Chiao Chao
- Department of Biology, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
- Institute of Environmental Change and Society, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Andrew D S Cameron
- Department of Biology, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
- Institute for Microbial Systems and Society, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
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46
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Zamora M, Ziegler CA, Freddolino PL, Wolfe AJ. A Thermosensitive, Phase-Variable Epigenetic Switch: pap Revisited. Microbiol Mol Biol Rev 2020; 84:e00030-17. [PMID: 32727743 PMCID: PMC7392537 DOI: 10.1128/mmbr.00030-17] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
It has been more than a decade since the last comprehensive review of the phase-variable uropathogen-associated pyelonephritis-associated pilus (pap) genetic switch. Since then, important data have come to light, including additional factors that regulate pap expression, better characterization of H-NS regulation, the structure of the Lrp octamer in complex with pap regulatory DNA, the temperature-insensitive phenotype of a mutant lacking the acetyltransferase RimJ, evidence that key components of the regulatory machinery are acetylated, and new insights into the role of DNA binding by key regulators in shaping both the physical structure and regulatory state of the papI and papBA promoters. This review revisits pap, integrating these newer observations with older ones to produce a new model for the concerted behavior of this virulence-regulatory region.
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Affiliation(s)
- Mario Zamora
- Stritch School of Medicine, Health Sciences Division, Loyola University Chicago, Maywood, Illinois, USA
- Department of Microbiology and Immunology, Stritch School of Medicine, Health Sciences Division, Loyola University Chicago, Maywood, Illinois, USA
| | - Christine A Ziegler
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Peter L Freddolino
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, USA
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Alan J Wolfe
- Department of Microbiology and Immunology, Stritch School of Medicine, Health Sciences Division, Loyola University Chicago, Maywood, Illinois, USA
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47
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Warman EA, Singh SS, Gubieda AG, Grainger DC. A non-canonical promoter element drives spurious transcription of horizontally acquired bacterial genes. Nucleic Acids Res 2020; 48:4891-4901. [PMID: 32297955 PMCID: PMC7229825 DOI: 10.1093/nar/gkaa244] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 03/30/2020] [Accepted: 04/01/2020] [Indexed: 01/18/2023] Open
Abstract
RNA polymerases initiate transcription at DNA sequences called promoters. In bacteria, the best conserved promoter feature is the AT-rich -10 element; a sequence essential for DNA unwinding. Further elements, and gene regulatory proteins, are needed to recruit RNA polymerase to the -10 sequence. Hence, -10 elements cannot function in isolation. Many horizontally acquired genes also have a high AT-content. Consequently, sequences that resemble the -10 element occur frequently. As a result, foreign genes are predisposed to spurious transcription. However, it is not clear how RNA polymerase initially recognizes such sequences. Here, we identify a non-canonical promoter element that plays a key role. The sequence, itself a short AT-tract, resides 5 base pairs upstream of otherwise cryptic -10 elements. The AT-tract alters DNA conformation and enhances contacts between the DNA backbone and RNA polymerase.
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Affiliation(s)
- Emily A Warman
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Shivani S Singh
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Alicia G Gubieda
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - David C Grainger
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
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48
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Yousuf M, Iuliani I, Veetil RT, Seshasayee A, Sclavi B, Cosentino Lagomarsino M. Early fate of exogenous promoters in E. coli. Nucleic Acids Res 2020; 48:2348-2356. [PMID: 31960057 PMCID: PMC7049719 DOI: 10.1093/nar/gkz1196] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 12/05/2019] [Accepted: 12/20/2019] [Indexed: 01/12/2023] Open
Abstract
Gene gain by horizontal gene transfer is a major pathway of genome innovation in bacteria. The current view posits that acquired genes initially need to be silenced and that a bacterial chromatin protein, H-NS, plays a role in this silencing. However, we lack direct observation of the early fate of a horizontally transferred gene to prove this theory. We combine sequencing, flow cytometry and sorting, followed by microscopy to monitor gene expression and its variability after large-scale random insertions of a reporter gene in a population of Escherichia coli bacteria. We find that inserted promoters have a wide range of gene-expression variability related to their location. We find that high-expression clones carry insertions that are not correlated with H-NS binding. Conversely, binding of H-NS correlates with silencing. Finally, while most promoters show a common level of extrinsic noise, some insertions show higher noise levels. Analysis of these high-noise clones supports a scenario of switching due to transcriptional interference from divergent ribosomal promoters. Altogether, our findings point to evolutionary pathways where newly-acquired genes are not necessarily silenced, but may immediately explore a wide range of expression levels to probe the optimal ones.
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Affiliation(s)
- Malikmohamed Yousuf
- LBPA, UMR 8113, CNRS, ENS Paris-Saclay, 61 Avenue du President Wilson, 94235 Cachan, France
- Current Affiliation: Centre for Clinical Brain Sciences, The University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Ilaria Iuliani
- LBPA, UMR 8113, CNRS, ENS Paris-Saclay, 61 Avenue du President Wilson, 94235 Cachan, France
- Current Affiliation: LCQB, UMR 7238, Sorbonne Université, 4 Place Jussieu, 75005 Paris, France
| | - Reshma T Veetil
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore 560065, Karnataka, India
- School of Life science, The University of Trans-Disciplinary Health Sciences and Technology (TDU), Bengaluru 560064, Karnataka, India
| | - Aswin Sai Narain Seshasayee
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore 560065, Karnataka, India
| | - Bianca Sclavi
- LBPA, UMR 8113, CNRS, ENS Paris-Saclay, 61 Avenue du President Wilson, 94235 Cachan, France
- Current Affiliation: LCQB, UMR 7238, Sorbonne Université, 4 Place Jussieu, 75005 Paris, France
| | - Marco Cosentino Lagomarsino
- Sorbonne Université, Campus Pierre and Marie Curie, 4 Place Jussieu, 75005 Paris, France
- CNRS, UMR7238, 4 Place Jussieu, 75005 Paris, France
- Current Affiliation: IFOM, FIRC Institute of Molecular Oncology, Via Adamello 16, 20143 Milan, Italy
- Current Affiliation: Physics Department, University of Milan, and I.N.F.N., Via Celoria 16, 20133 Milan, Italy
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49
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Qin L, Bdira FB, Sterckx YGJ, Volkov AN, Vreede J, Giachin G, van Schaik P, Ubbink M, Dame R. Structural basis for osmotic regulation of the DNA binding properties of H-NS proteins. Nucleic Acids Res 2020; 48:2156-2172. [PMID: 31925429 PMCID: PMC7039000 DOI: 10.1093/nar/gkz1226] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 11/29/2019] [Accepted: 12/19/2019] [Indexed: 01/07/2023] Open
Abstract
H-NS proteins act as osmotic sensors translating changes in osmolarity into altered DNA binding properties, thus, regulating enterobacterial genome organization and genes transcription. The molecular mechanism underlying the switching process and its conservation among H-NS family members remains elusive. Here, we focus on the H-NS family protein MvaT from Pseudomonas aeruginosa and demonstrate experimentally that its protomer exists in two different conformations, corresponding to two different functional states. In the half-opened state (dominant at low salt) the protein forms filaments along DNA, in the fully opened state (dominant at high salt) the protein bridges DNA. This switching is a direct effect of ionic strength on electrostatic interactions between the oppositely charged DNA binding and N-terminal domains of MvaT. The asymmetric charge distribution and intramolecular interactions are conserved among the H-NS family of proteins. Therefore, our study establishes a general paradigm for the molecular mechanistic basis of the osmosensitivity of H-NS proteins.
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Affiliation(s)
- Liang Qin
- Department of Macromolecular Biochemistry, Leiden Institute of Chemistry, Einsteinweg 55, 2333 CC Leiden, the Netherlands
- Centre for Microbial Cell Biology, Leiden University, Einsteinweg 55, 2333CC Leiden, the Netherlands
| | - Fredj Ben Bdira
- Department of Macromolecular Biochemistry, Leiden Institute of Chemistry, Einsteinweg 55, 2333 CC Leiden, the Netherlands
- Centre for Microbial Cell Biology, Leiden University, Einsteinweg 55, 2333CC Leiden, the Netherlands
| | - Yann G J Sterckx
- Laboratory of Medical Biochemistry, University of Antwerp, Campus Drie Eiken, University Square 1, 2610 Wilrijk, Belgium
| | - Alexander N Volkov
- VIB-VUB Structural Biology Research Center, Pleinlaan 2, 1050 Brussels, Belgium
- Jean Jeener NMR Centre, VUB, Pleinlaan 2, 1050 Brussels, Belgium
| | - Jocelyne Vreede
- Department of Computational Chemistry, Van’t Hoff Institute for Molecular Sciences, University of Amsterdam Science Park 904, 1098 XH Amsterdam, the Netherlands
| | - Gabriele Giachin
- Structural Biology Group, European Synchrotron Radiation Facility (ESRF), Grenoble, France
| | - Peter van Schaik
- Department of Macromolecular Biochemistry, Leiden Institute of Chemistry, Einsteinweg 55, 2333 CC Leiden, the Netherlands
- Centre for Microbial Cell Biology, Leiden University, Einsteinweg 55, 2333CC Leiden, the Netherlands
| | - Marcellus Ubbink
- Department of Macromolecular Biochemistry, Leiden Institute of Chemistry, Einsteinweg 55, 2333 CC Leiden, the Netherlands
| | - Remus T Dame
- Department of Macromolecular Biochemistry, Leiden Institute of Chemistry, Einsteinweg 55, 2333 CC Leiden, the Netherlands
- Centre for Microbial Cell Biology, Leiden University, Einsteinweg 55, 2333CC Leiden, the Netherlands
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O'Boyle N, Turner NCA, Roe AJ, Connolly JPR. Plastic Circuits: Regulatory Flexibility in Fine Tuning Pathogen Success. Trends Microbiol 2020; 28:360-371. [PMID: 32298614 DOI: 10.1016/j.tim.2020.01.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 01/07/2020] [Accepted: 01/16/2020] [Indexed: 12/30/2022]
Abstract
Bacterial pathogens employ diverse fitness and virulence mechanisms to gain an advantage in competitive niches. These lifestyle-specific traits require integration into the regulatory network of the cell and are often controlled by pre-existing transcription factors. In this review, we highlight recent advances that have been made in characterizing this regulatory flexibility in prominent members of the Enterobacteriaceae. We focus on the direct global interactions between transcription factors and their target genes in pathogenic Escherichia coli and Salmonella revealed using chromatin immunoprecipitation coupled with next-generation sequencing. Furthermore, the implications and advantages of such regulatory adaptations in benefiting distinct pathogenic lifestyles are discussed.
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Affiliation(s)
- Nicky O'Boyle
- Institute of Infection, Immunity, and Inflammation, University of Glasgow, Glasgow, G12 8TA, UK
| | - Natasha C A Turner
- Institute of Infection, Immunity, and Inflammation, University of Glasgow, Glasgow, G12 8TA, UK
| | - Andrew J Roe
- Institute of Infection, Immunity, and Inflammation, University of Glasgow, Glasgow, G12 8TA, UK.
| | - James P R Connolly
- Institute of Infection, Immunity, and Inflammation, University of Glasgow, Glasgow, G12 8TA, UK; Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle-upon-Tyne, NE2 4HH, UK.
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