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Raheem A, Lu D, Khalid AK, Zhao G, Fu Y, Chen Y, Chen X, Hu C, Chen J, Chen H, Guo A. The Identification of a Novel Nucleomodulin MbovP467 of Mycoplasmopsis bovis and Its Potential Contribution in Pathogenesis. Cells 2024; 13:604. [PMID: 38607043 PMCID: PMC11011252 DOI: 10.3390/cells13070604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 03/23/2024] [Accepted: 03/26/2024] [Indexed: 04/13/2024] Open
Abstract
Mycoplasmopsis bovis is a causative agent of crucial diseases in both dairy and beef cattle leading to substantial economic losses. However, limited control measures for M. bovis-related diseases exist due to a lack of understanding about the virulence factors of this pathogen, a common challenge in mycoplasma research. Consequently, this study aimed to characterize a novel nucleomodulin as a virulence-related factor of M. bovis. Employing bioinformatic tools, we initially predicted MbovP467 to be a secreted protein with a nuclear localization signal based on SignalP scores and the cNLS (Nuclear Localization Signal) Mapper, respectively. Subsequently, the MbovP467 gene was synthesized and cloned into a pEGFP plasmid with EGFP labeling to obtain a recombinant plasmid (rpEGFP-MbovP467) and then was also cloned in pET-30a with a consideration for an Escherichia coli codon bias and expressed and purified for the production of polyclonal antibodies against the recombinant MbovP467 protein. Confocal microscopy and a Western blotting assay confirmed the nuclear location of MbovP467 in bovine macrophages (BoMacs). RNA-seq data revealed 220 up-regulated and 20 down-regulated genes in the rpEGFP-MbovP467-treated BoMac group compared to the control group (pEGFP). A GO- and KEGG-enrichment analysis identified associations with inflammatory responses, G protein-coupled receptor signaling pathways, nuclear receptor activity, sequence-specific DNA binding, the regulation of cell proliferation, IL-8, apoptotic processes, cell growth and death, the TNF signaling pathway, the NF-κB signaling pathway, pathways in cancer, and protein families of signaling and cellular processes among the differentially expressed up-regulated mRNAs. Further experiments, investigating cell viability and the inflammatory response, demonstrated that MbovP467 reduces BoMac cell viability and induces the mRNA expression of IL-1β, IL-6, IL-8, TNF-α, and apoptosis in BoMac cells. Further, MbovP467 increased the promoter activity of TNF-α. In conclusion, this study identified a new nucleomodulin, MbovP467, for M. bovis, which might have an important role in M. bovis pathogenesis.
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Affiliation(s)
- Abdul Raheem
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (A.R.); (D.L.); (A.K.K.); (Y.F.); (Y.C.); (X.C.); (C.H.); (J.C.); (H.C.)
- Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Doukun Lu
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (A.R.); (D.L.); (A.K.K.); (Y.F.); (Y.C.); (X.C.); (C.H.); (J.C.); (H.C.)
- Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Abdul Karim Khalid
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (A.R.); (D.L.); (A.K.K.); (Y.F.); (Y.C.); (X.C.); (C.H.); (J.C.); (H.C.)
- Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Gang Zhao
- Key Laboratory of Ministry of Education for Conservation and Utilization of Special Biological Resources in the Western China, School of Life Sciences, Ningxia University, Yinchuan 750021, China;
| | - Yingjie Fu
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (A.R.); (D.L.); (A.K.K.); (Y.F.); (Y.C.); (X.C.); (C.H.); (J.C.); (H.C.)
- Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Yingyu Chen
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (A.R.); (D.L.); (A.K.K.); (Y.F.); (Y.C.); (X.C.); (C.H.); (J.C.); (H.C.)
- Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Xi Chen
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (A.R.); (D.L.); (A.K.K.); (Y.F.); (Y.C.); (X.C.); (C.H.); (J.C.); (H.C.)
- Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Changmin Hu
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (A.R.); (D.L.); (A.K.K.); (Y.F.); (Y.C.); (X.C.); (C.H.); (J.C.); (H.C.)
- Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Jianguo Chen
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (A.R.); (D.L.); (A.K.K.); (Y.F.); (Y.C.); (X.C.); (C.H.); (J.C.); (H.C.)
- Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Huanchun Chen
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (A.R.); (D.L.); (A.K.K.); (Y.F.); (Y.C.); (X.C.); (C.H.); (J.C.); (H.C.)
- Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Aizhen Guo
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (A.R.); (D.L.); (A.K.K.); (Y.F.); (Y.C.); (X.C.); (C.H.); (J.C.); (H.C.)
- Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
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Pittner NA, Solomon RN, Bui DC, McBride JW. Ehrlichia effector SLiM-icry: Artifice of cellular subversion. Front Cell Infect Microbiol 2023; 13:1150758. [PMID: 36960039 PMCID: PMC10028187 DOI: 10.3389/fcimb.2023.1150758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 02/23/2023] [Indexed: 03/09/2023] Open
Abstract
As an obligately intracellular bacterial pathogen that selectively infects the mononuclear phagocyte, Ehrlichia chaffeensis has evolved sophisticated mechanisms to subvert innate immune defenses. While the bacterium accomplishes this through a variety of mechanisms, a rapidly expanding body of evidence has revealed that E. chaffeensis has evolved survival strategies that are directed by the versatile, intrinsically disordered, 120 kDa tandem repeat protein (TRP120) effector. E. chaffeensis establishes infection by manipulating multiple evolutionarily conserved cellular signaling pathways through effector-host interactions to subvert innate immune defenses. TRP120 activates these pathways using multiple functionally distinct, repetitive, eukaryote-mimicking short linear motifs (SLiMs) located within the tandem repeat domain that have evolved in nihilo. Functionally, the best characterized TRP120 SLiMs mimic eukaryotic ligands (SLiM-icry) to engage pathway-specific host receptors and activate cellular signaling, thereby repurposing these pathways to promote infection. Moreover, E. chaffeensis TRP120 contains SLiMs that are targets of post-translational modifications such as SUMOylation in addition to many other validated SLiMs that are curated in the eukaryotic linear motif (ELM) database. This review will explore the extracellular and intracellular roles TRP120 SLiM-icry plays during infection - mediated through a variety of SLiMs - that enable E. chaffeensis to subvert mononuclear phagocyte innate defenses.
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Affiliation(s)
- Nicholas A. Pittner
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States
| | - Regina N. Solomon
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States
| | - Duc-Cuong Bui
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States
| | - Jere W. McBride
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
- Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, TX, United States
- Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX, United States
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, United States
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Zhao G, Lu D, Wang S, Zhang H, Zhu X, Hao Z, Dawood A, Chen Y, Schieck E, Hu C, Chen X, Yang L, Guo A. Novel mycoplasma nucleomodulin MbovP475 decreased cell viability by regulating expression of CRYAB and MCF2L2. Virulence 2022; 13:1590-1613. [PMID: 36121023 PMCID: PMC9487752 DOI: 10.1080/21505594.2022.2117762] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Nucleomodulins are secreted bacterial proteins whose molecular targets are located in host cell nuclei. They are gaining attention as critical virulence factors that either modify the epigenetics of host cells or directly regulate host gene expression. Mycoplasma bovis is a major veterinary pathogen that secretes several potential virulence factors. The aim of this study was to determine whether any of their secreted proteins might function as nucleomodulins. After an initial in silico screening, the nuclear localization of the secreted putative lipoprotein MbovP475 of M. bovis was demonstrated in bovine macrophage cell line (BoMac) experimentally infected with M. bovis. Through combined application of ChIP-seq, Electrophoretic mobility shift assay (EMSA) and surface plasmon resonance (SPR) analysis, MbovP475 was determined to bind the promoter regions of the cell cycle central regulatory genes CRYAB and MCF2L2. MbovP475 has similar secondary structures with the transcription activator-like effectors (TALEs). Screening of various mutants affecting the potential DNA binding sites indicated that the residues 242NI243 within MbovP475 loop region of the helix-loop-helix domain were essential to its DNA binding activity, thereby contributing to decrease in BoMac cell viability. In conclusion, this is the first report to confirm M. bovis secretes a conserved TALE-like nucleomodulin that binds the promoters of CRYAB and MCF2L2 genes, and subsequently down-regulates their expression and decreases BoMac cell viability. Therefore, this study offers a new understanding of mycoplasma pathogenesis.
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Affiliation(s)
- Gang Zhao
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.,College of Animal Science and Technology, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, China
| | - Doukun Lu
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Shujuan Wang
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Hui Zhang
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Xifang Zhu
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Zhiyu Hao
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Ali Dawood
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Yingyu Chen
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,Key Laboratory of Ruminant Bio-products of Ministry of Agriculture and Rural Affairs, Huazhong Agriculture University, Wuhan, China.,International Research Center for Animal Disease, Ministry of Science and Technology, Huazhong Agricultural University, Wuhan, China.,International Livestock Research Institute, Nairobi, Kenya
| | - Elise Schieck
- Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan, China
| | - Changmin Hu
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Xi Chen
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Liguo Yang
- College of Animal Science and Technology, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, China
| | - Aizhen Guo
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.,Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan, China
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Adcox HE, Hatke AL, Andersen SE, Gupta S, Otto NB, Weber MM, Marconi RT, Carlyon JA. Orientia tsutsugamushi Nucleomodulin Ank13 Exploits the RaDAR Nuclear Import Pathway To Modulate Host Cell Transcription. mBio 2021; 12:e0181621. [PMID: 34340535 DOI: 10.1128/mBio.01816-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Orientia tsutsugamushi is the etiologic agent of scrub typhus, the deadliest of all diseases caused by obligate intracellular bacteria. Nucleomodulins, bacterial effectors that dysregulate eukaryotic transcription, are being increasingly recognized as key virulence factors. How they translocate into the nucleus and their functionally essential domains are poorly defined. We demonstrate that Ank13, an O. tsutsugamushi effector conserved among clinical isolates and expressed during infection, localizes to the nucleus in an importin β1-independent manner. Rather, Ank13 nucleotropism requires an isoleucine at the thirteenth position of its fourth ankyrin repeat, consistent with utilization of eukaryotic RaDAR (RanGDP-ankyrin repeats) nuclear import. RNA-seq analyses of cells expressing green fluorescent protein (GFP)-tagged Ank13, nucleotropism-deficient Ank13I127R, or Ank13ΔF-box, which lacks the F-box domain essential for interacting with SCF ubiquitin ligase, revealed Ank13 to be a nucleomodulin that predominantly downregulates transcription of more than 2,000 genes. Its ability to do so involves its nucleotropism and F-box in synergistic and mutually exclusive manners. Ank13 also acts in the cytoplasm to dysregulate smaller cohorts of genes. The effector’s toxicity in yeast heavily depends on its F-box and less so on its nucleotropism. Genes negatively regulated by Ank13 include those involved in the inflammatory response, transcriptional control, and epigenetics. Importantly, the majority of genes that GFP-Ank13 most strongly downregulates are quiescent or repressed in O. tsutsugamushi-infected cells when Ank13 expression is strongest. Ank13 is the first nucleomodulin identified to coopt RaDAR and a multifaceted effector that functions in the nucleus and cytoplasm via F-box-dependent and -independent mechanisms to globally reprogram host cell transcription.
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Bierne H, Hamon M. Targeting host epigenetic machinery: The Listeria paradigm. Cell Microbiol 2021; 22:e13169. [PMID: 32185898 DOI: 10.1111/cmi.13169] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 01/22/2020] [Accepted: 01/22/2020] [Indexed: 12/11/2022]
Abstract
By modifying the host cell transcription programme, pathogenic bacteria disrupt a wide range of cellular processes and take control of the host's immune system. Conversely, by mobilising a network of defence genes, the host cells trigger various responses that allow them to tolerate or eliminate invaders. The study of the molecular basis of this crosstalk is crucial to the understanding of infectious diseases. Although research has long focused on the targeting of eukaryotic DNA-binding transcription factors, more recently, another powerful way by which bacteria modify the expression of host genes has emerged: chromatin modifications in the cell nucleus. One of the most prolific bacterial models in this area has been Listeria monocytogenes, a facultative intracellular bacterium responsible for serious food-borne infections. Here, we aim to highlight the contribution of this model to the field of bacteria-mediated chromatin modifications. We will first recall the general principles of epigenetic regulation and then illustrate five mechanisms that mobilise the epigenetic machinery in response to Listeria factors, either through bacterial molecular patterns, a toxin, an invasion protein, or nucleomodulins. Strategies used by Listeria to control the expression of host genes at the chromatin level, by activation of cytosolic signalling pathways or direct targeting of epifactors in the nucleus, have contributed to the emergence of a new discipline combining cellular microbiology and epigenetics: "patho-epigenetics."
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Affiliation(s)
- Hélène Bierne
- Université Paris Saclay, INRAE, AgroParisTech, Micalis Institute, Epigenetics and Cellular Microbiology Team, Jouy-en-Josas, France
| | - Mélanie Hamon
- G5 Chromatin and Infection, Institut Pasteur, Paris, France
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Le LHM, Ying L, Ferrero RL. Nuclear trafficking of bacterial effector proteins. Cell Microbiol 2021; 23:e13320. [PMID: 33600054 DOI: 10.1111/cmi.13320] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 02/08/2021] [Accepted: 02/09/2021] [Indexed: 02/06/2023]
Abstract
Bacterial pathogens can subvert host responses by producing effector proteins that directly target the nucleus of eukaryotic cells in animals and plants. Nuclear-targeting proteins are categorised as either: "nucleomodulins," which have epigenetic-modulating activities; or "cyclomodulins," which specifically interfere with the host cell cycle. Bacteria can deliver these effector proteins to eukaryotic cells via a range of strategies. Despite an increasing number of reports describing the effects of bacterial effector proteins on nuclear processes in host cells, the intracellular pathways used by these proteins to traffic to the nucleus have yet to be fully elucidated. This review will describe current knowledge about how nucleomodulins and cyclomodulins enter eukaryotic cells, exploit endocytic pathways and translocate to the nucleus. We will also discuss the secretion of nuclear-targeting proteins or their release in bacterial membrane vesicles and the trafficking pathways employed by each of these forms. Besides their importance for bacterial pathogenesis, some nuclear-targeting proteins have been implicated in the development of chronic diseases and even cancer. A greater understanding of nuclear-targeting proteins and their actions will provide new insights into the pathogenesis of infectious diseases, as well as contribute to advances in the development of novel therapies against bacterial infections and possibly cancer.
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Affiliation(s)
- Lena Hoang My Le
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Biomedicine Discovery Institute, Department of Microbiology, Monash University, Melbourne, Victoria, Australia
| | - Le Ying
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Richard L Ferrero
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Biomedicine Discovery Institute, Department of Microbiology, Monash University, Melbourne, Victoria, Australia.,Department of Molecular and Translational Science, Monash University, Melbourne, Victoria, Australia
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Ma Z, Li R, Hu R, Deng X, Xu Y, Zheng W, Yi J, Wang Y, Chen C. Brucella abortus BspJ Is a Nucleomodulin That Inhibits Macrophage Apoptosis and Promotes Intracellular Survival of Brucella. Front Microbiol 2020; 11:599205. [PMID: 33281799 PMCID: PMC7688787 DOI: 10.3389/fmicb.2020.599205] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 10/23/2020] [Indexed: 12/11/2022] Open
Abstract
To date, a variety of Brucella effector proteins have been found to mediate host cell secretion, autophagy, inflammation, and other signal pathways, but nuclear effector proteins have not yet been reported. We identified the first Brucella nucleomodulin, BspJ, and we screened out the BspJ interaction host proteins NME/NM23 nucleoside diphosphate kinase 2 (NME2) and creatine kinase B (CKB) through yeast two-hybrid and co-immunoprecipitation assays. These proteins are related to the host cell energy synthesis, metabolism, and apoptosis pathways. Brucella nucleomodulin BspJ will decrease the expression level of NME2 and CKB. In addition, BspJ gene deletion strains promoted the apoptosis of macrophages and reduced the intracellular survival of Brucella in host cells. In short, we found nucleomodulin BspJ may directly or indirectly regulate host cell apoptosis through the interaction with NME2 and CKB by mediating energy metabolism pathways in response to the intracellular circulation of Brucella infection, but the mechanism needs further study.
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Affiliation(s)
- Zhongchen Ma
- International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, College of Animal Science and Technology, Shihezi University, Shihezi, China
- Key Laboratory of Control and Prevention of Animal Disease, Xinjiang Production & Construction Corps, College of Animal Science and Technology, Shihezi University, Shihezi, China
| | - Ruirui Li
- International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, College of Animal Science and Technology, Shihezi University, Shihezi, China
- Key Laboratory of Control and Prevention of Animal Disease, Xinjiang Production & Construction Corps, College of Animal Science and Technology, Shihezi University, Shihezi, China
| | - Ruirui Hu
- College of Life Science, Shihezi University, Shihezi, China
| | - Xiaoyu Deng
- International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, College of Animal Science and Technology, Shihezi University, Shihezi, China
- Key Laboratory of Control and Prevention of Animal Disease, Xinjiang Production & Construction Corps, College of Animal Science and Technology, Shihezi University, Shihezi, China
| | - Yimei Xu
- Xinjiang Center for Disease Control and Prevention, Urumqi, China
| | - Wei Zheng
- International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, College of Animal Science and Technology, Shihezi University, Shihezi, China
- Key Laboratory of Control and Prevention of Animal Disease, Xinjiang Production & Construction Corps, College of Animal Science and Technology, Shihezi University, Shihezi, China
| | - Jihai Yi
- International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, College of Animal Science and Technology, Shihezi University, Shihezi, China
- Key Laboratory of Control and Prevention of Animal Disease, Xinjiang Production & Construction Corps, College of Animal Science and Technology, Shihezi University, Shihezi, China
| | - Yong Wang
- International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, College of Animal Science and Technology, Shihezi University, Shihezi, China
- Key Laboratory of Control and Prevention of Animal Disease, Xinjiang Production & Construction Corps, College of Animal Science and Technology, Shihezi University, Shihezi, China
| | - Chuangfu Chen
- International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, College of Animal Science and Technology, Shihezi University, Shihezi, China
- Key Laboratory of Control and Prevention of Animal Disease, Xinjiang Production & Construction Corps, College of Animal Science and Technology, Shihezi University, Shihezi, China
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Bierne H, Pourpre R. Bacterial Factors Targeting the Nucleus: The Growing Family of Nucleomodulins. Toxins (Basel) 2020; 12:E220. [PMID: 32244550 DOI: 10.3390/toxins12040220] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 03/23/2020] [Accepted: 03/29/2020] [Indexed: 12/18/2022] Open
Abstract
Pathogenic bacteria secrete a variety of proteins that manipulate host cell function by targeting components of the plasma membrane, cytosol, or organelles. In the last decade, several studies identified bacterial factors acting within the nucleus on gene expression or other nuclear processes, which has led to the emergence of a new family of effectors called “nucleomodulins”. In human and animal pathogens, Listeria monocytogenes for Gram-positive bacteria and Anaplasma phagocytophilum, Ehrlichia chaffeensis, Chlamydia trachomatis, Legionella pneumophila, Shigella flexneri, and Escherichia coli for Gram-negative bacteria, have led to pioneering discoveries. In this review, we present these paradigms and detail various mechanisms and core elements (e.g., DNA, histones, epigenetic regulators, transcription or splicing factors, signaling proteins) targeted by nucleomodulins. We particularly focus on nucleomodulins interacting with epifactors, such as LntA of Listeria and ankyrin repeat- or tandem repeat-containing effectors of Rickettsiales, and nucleomodulins from various bacterial species acting as post-translational modification enzymes. The study of bacterial nucleomodulins not only generates important knowledge about the control of host responses by microbes but also creates new tools to decipher the dynamic regulations that occur in the nucleus. This research also has potential applications in the field of biotechnology. Finally, this raises questions about the epigenetic effects of infectious diseases.
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Schuelein R, Spencer H, Dagley LF, Li PF, Luo L, Stow JL, Abraham G, Naderer T, Gomez-Valero L, Buchrieser C, Sugimoto C, Yamagishi J, Webb AI, Pasricha S, Hartland EL. Targeting of RNA Polymerase II by a nuclear Legionella pneumophila Dot/Icm effector SnpL. Cell Microbiol 2018; 20:e12852. [PMID: 29691989 DOI: 10.1111/cmi.12852] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 03/24/2018] [Accepted: 04/11/2018] [Indexed: 12/28/2022]
Abstract
The intracellular pathogen Legionella pneumophila influences numerous eukaryotic cellular processes through the Dot/Icm-dependent translocation of more than 300 effector proteins into the host cell. Although many translocated effectors localise to the Legionella replicative vacuole, other effectors can affect remote intracellular sites. Following infection, a subset of effector proteins localises to the nucleus where they subvert host cell transcriptional responses to infection. Here, we identified Lpw27461 (Lpp2587), Lpg2519 as a new nuclear-localised effector that we have termed SnpL. Upon ectopic expression or during L. pneumophila infection, SnpL showed strong nuclear localisation by immunofluorescence microscopy but was excluded from nucleoli. Using immunoprecipitation and mass spectrometry, we determined the host-binding partner of SnpL as the eukaryotic transcription elongation factor, Suppressor of Ty5 (SUPT5H)/Spt5. SUPT5H is an evolutionarily conserved component of the DRB sensitivity-inducing factor complex that regulates RNA Polymerase II dependent mRNA processing and transcription elongation. Protein interaction studies showed that SnpL bound to the central Kyprides, Ouzounis, Woese motif region of SUPT5H. Ectopic expression of SnpL led to massive upregulation of host gene expression and macrophage cell death. The activity of SnpL further highlights the ability of L. pneumophila to control fundamental eukaryotic processes such as transcription that, in the case of SnpL, leads to global upregulation of host gene expression.
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Affiliation(s)
- Ralf Schuelein
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Hugh Spencer
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Laura F Dagley
- The Walter and Eliza Hall Institute of Medical Research and Department of Medical Biology, University of Melbourne, Parkville, Australia
| | - Peng Fei Li
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia.,Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Australia
| | - Lin Luo
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Jennifer L Stow
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Gilu Abraham
- Biomedicine Discovery Institute and Department of Biochemistry & Molecular Biology, Monash University, Clayton, Australia
| | - Thomas Naderer
- Biomedicine Discovery Institute and Department of Biochemistry & Molecular Biology, Monash University, Clayton, Australia
| | - Laura Gomez-Valero
- Institut Pasteur, Biologie des Bactéries Intracellulaires, Paris, France.,CNRS UMR 3525, Paris, France
| | - Carmen Buchrieser
- Institut Pasteur, Biologie des Bactéries Intracellulaires, Paris, France.,CNRS UMR 3525, Paris, France
| | - Chihiro Sugimoto
- Global Station for Zoonosis Control, GI-CoRE, Hokkaido University, Sapporo, Hokkaido, Japan.,Research Center for Zoonosis Control, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Junya Yamagishi
- Global Station for Zoonosis Control, GI-CoRE, Hokkaido University, Sapporo, Hokkaido, Japan.,Research Center for Zoonosis Control, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Andrew I Webb
- The Walter and Eliza Hall Institute of Medical Research and Department of Medical Biology, University of Melbourne, Parkville, Australia
| | - Shivani Pasricha
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia.,Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Australia
| | - Elizabeth L Hartland
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia.,Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Australia.,Institut Pasteur, Biologie des Bactéries Intracellulaires, Paris, France.,Department of Molecular and Translational Science, Monash University, Clayton, Australia
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Prokop A, Gouin E, Villiers V, Nahori MA, Vincentelli R, Duval M, Cossart P, Dussurget O. OrfX, a Nucleomodulin Required for Listeria monocytogenes Virulence. mBio 2017; 8:e01550-17. [PMID: 29089430 PMCID: PMC5666158 DOI: 10.1128/mbio.01550-17] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 09/25/2017] [Indexed: 12/11/2022] Open
Abstract
Listeria monocytogenes is a bacterial pathogen causing severe foodborne infections in humans and animals. Listeria can enter into host cells and survive and multiply therein, due to an arsenal of virulence determinants encoded in different loci on the chromosome. Several key Listeria virulence genes are clustered in Listeria pathogenicity island 1. This important locus also contains orfX (lmo0206), a gene of unknown function. Here, we found that OrfX is a small, secreted protein whose expression is positively regulated by PrfA, the major transcriptional activator of Listeria virulence genes. We provide evidence that OrfX is a virulence factor that dampens the oxidative response of infected macrophages, which contributes to intracellular survival of bacteria. OrfX is targeted to the nucleus and interacts with the regulatory protein RybP. We show that in macrophages, the expression of OrfX decreases the level of RybP, which controls cellular infection. Collectively, these data reveal that Listeria targets RybP and evades macrophage oxidative stress for efficient infection. Altogether, OrfX is after LntA, the second virulence factor acting directly in the nucleus.IMPORTANCEListeria monocytogenes is a model bacterium that has been successfully used over the last 30 years to refine our understanding of the molecular, cellular, and tissular mechanisms of microbial pathogenesis. The major virulence factors of pathogenic Listeria species are located on a single chromosomal locus. Here, we report that the last gene of this locus encodes a small secreted nucleomodulin, OrfX, that is required for bacterial survival within macrophages and in the infected host. This work demonstrates that the production of OrfX contributes to limiting the host innate immune response by dampening the oxidative response of macrophages. We also identify a target of OrfX, RybP, which is an essential pleiotropic regulatory protein of the cell, and uncover its role in host defense. Our data reinforce the view that the secretion of nucleomodulins is an important strategy used by microbial pathogens to promote infection.
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Affiliation(s)
- Andrzej Prokop
- Institut Pasteur, Unité des Interactions Bactéries-Cellules, Paris, France
- Inserm, U604, Paris, France
- INRA, USC2020, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Edith Gouin
- Institut Pasteur, Unité des Interactions Bactéries-Cellules, Paris, France
- Inserm, U604, Paris, France
- INRA, USC2020, Paris, France
| | - Véronique Villiers
- Institut Pasteur, Unité des Interactions Bactéries-Cellules, Paris, France
- Inserm, U604, Paris, France
- INRA, USC2020, Paris, France
| | - Marie-Anne Nahori
- Institut Pasteur, Unité des Interactions Bactéries-Cellules, Paris, France
- Inserm, U604, Paris, France
- INRA, USC2020, Paris, France
| | | | - Mélodie Duval
- Institut Pasteur, Unité des Interactions Bactéries-Cellules, Paris, France
- Inserm, U604, Paris, France
- INRA, USC2020, Paris, France
| | - Pascale Cossart
- Institut Pasteur, Unité des Interactions Bactéries-Cellules, Paris, France
- Inserm, U604, Paris, France
- INRA, USC2020, Paris, France
| | - Olivier Dussurget
- Institut Pasteur, Unité des Interactions Bactéries-Cellules, Paris, France
- Inserm, U604, Paris, France
- INRA, USC2020, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Paris, France
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Sinclair SHG, Garcia-Garcia JC, Dumler JS. Bioinformatic and mass spectrometry identification of Anaplasma phagocytophilum proteins translocated into host cell nuclei. Front Microbiol 2015; 6:55. [PMID: 25705208 PMCID: PMC4319465 DOI: 10.3389/fmicb.2015.00055] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 01/16/2015] [Indexed: 12/22/2022] Open
Abstract
Obligate intracellular bacteria have an arsenal of proteins that alter host cells to establish and maintain a hospitable environment for replication. Anaplasma phagocytophilum secrets Ankyrin A (AnkA), via a type IV secretion system, which translocates to the nucleus of its host cell, human neutrophils. A. phagocytophilum-infected neutrophils have dramatically altered phenotypes in part explained by AnkA-induced transcriptional alterations. However, it is unlikely that AnkA is the sole effector to account for infection-induced transcriptional changes. We developed a simple method combining bioinformatics and iTRAQ protein profiling to identify potential bacterial-derived nuclear-translocated proteins that could impact transcriptional programming in host cells. This approach identified 50 A. phagocytophilum candidate genes or proteins. The encoding genes were cloned to create GFP fusion protein-expressing clones that were transfected into HEK-293T cells. We confirmed nuclear translocation of six proteins: APH_0062, RplE, Hup, APH_0382, APH_0385, and APH_0455. Of the six, APH_0455 was identified as a type IV secretion substrate and is now under investigation as a potential nucleomodulin. Additionally, application of this approach to other intracellular bacteria such as Mycobacterium tuberculosis, Chlamydia trachomatis and other intracellular bacteria identified multiple candidate genes to be investigated.
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Affiliation(s)
- Sara H G Sinclair
- Graduate Program in Cellular and Molecular Medicine, The Johns Hopkins University School of Medicine Baltimore, MD, USA ; Department of Pathology, The Johns Hopkins University School of Medicine Baltimore, MD, USA ; Department of Pathology, University of Maryland School of Medicine Baltimore, MD, USA ; Department of Microbiology and Immunology, University of Maryland School of Medicine Baltimore, MD, USA
| | - Jose C Garcia-Garcia
- Department of Pathology, The Johns Hopkins University School of Medicine Baltimore, MD, USA ; Procter and Gamble Co. Cincinnati, OH, USA
| | - J Stephen Dumler
- Graduate Program in Cellular and Molecular Medicine, The Johns Hopkins University School of Medicine Baltimore, MD, USA ; Department of Pathology, The Johns Hopkins University School of Medicine Baltimore, MD, USA ; Department of Pathology, University of Maryland School of Medicine Baltimore, MD, USA ; Department of Microbiology and Immunology, University of Maryland School of Medicine Baltimore, MD, USA
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12
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Sinclair SH, Rennoll-Bankert KE, Dumler JS. Effector bottleneck: microbial reprogramming of parasitized host cell transcription by epigenetic remodeling of chromatin structure. Front Genet 2014; 5:274. [PMID: 25177343 PMCID: PMC4132484 DOI: 10.3389/fgene.2014.00274] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 07/26/2014] [Indexed: 12/25/2022] Open
Abstract
Obligate intracellular pathogenic bacteria evolved to manipulate their host cells with a limited range of proteins constrained by their compact genomes. The harsh environment of a phagocytic defense cell is one that challenges the majority of commensal and pathogenic bacteria; yet, these are the obligatory vertebrate homes for important pathogenic species in the Anaplasmataceae family. Survival requires that the parasite fundamentally alter the native functions of the cell to allow its entry, intracellular replication, and transmission to a hematophagous arthropod. The small genomic repertoires encode several eukaryotic-like proteins, including ankyrin A (AnkA) of Anaplasma phagocytophilum and Ank200 and tandem-repeat containing proteins of Ehrlichia chaffeensis that localize to the host cell nucleus and directly bind DNA. As a model, A. phagocytophilum AnkA appears to directly alter host cell gene expression by recruiting chromatin modifying enzymes such as histone deacetylases and methyltransferases or by acting directly on transcription in cis. While cis binding could feasibly alter limited ranges of genes and cellular functions, the complex and dramatic alterations in transcription observed with infection are difficult to explain on the basis of individually targeted genes. We hypothesize that nucleomodulins can act broadly, even genome-wide, to affect entire chromosomal neighborhoods and topologically associating chromatin domains by recruiting chromatin remodeling complexes or by altering the folding patterns of chromatin that bring distant regulatory regions together to coordinate control of transcriptional reprogramming. This review focuses on the A. phagocytophilum nucleomodulin AnkA, how it impacts host cell transcriptional responses, and current investigations that seek to determine how these multifunctional eukaryotic-like proteins facilitate epigenetic alterations and cellular reprogramming at the chromosomal level.
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Affiliation(s)
- Sara H Sinclair
- Graduate Program in Cellular and Molecular Medicine, The Johns Hopkins University School of Medicine Baltimore, MD, USA ; Department of Microbiology and Immunology, School of Medicine, University of Maryland Baltimore Baltimore, MD, USA ; Department of Pathology, The Johns Hopkins University School of Medicine Baltimore, MD, USA ; Department of Pathology, School of Medicine, University of Maryland Baltimore Baltimore, MD, USA
| | - Kristen E Rennoll-Bankert
- Department of Microbiology and Immunology, School of Medicine, University of Maryland Baltimore Baltimore, MD, USA ; Department of Pathology, The Johns Hopkins University School of Medicine Baltimore, MD, USA
| | - J S Dumler
- Graduate Program in Cellular and Molecular Medicine, The Johns Hopkins University School of Medicine Baltimore, MD, USA ; Department of Microbiology and Immunology, School of Medicine, University of Maryland Baltimore Baltimore, MD, USA ; Department of Pathology, The Johns Hopkins University School of Medicine Baltimore, MD, USA ; Department of Pathology, School of Medicine, University of Maryland Baltimore Baltimore, MD, USA
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Stilling RM, Dinan TG, Cryan JF. Microbial genes, brain & behaviour - epigenetic regulation of the gut-brain axis. Genes Brain Behav 2013; 13:69-86. [PMID: 24286462 DOI: 10.1111/gbb.12109] [Citation(s) in RCA: 395] [Impact Index Per Article: 35.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Revised: 11/13/2013] [Accepted: 11/25/2013] [Indexed: 12/12/2022]
Abstract
To date, there is rapidly increasing evidence for host-microbe interaction at virtually all levels of complexity, ranging from direct cell-to-cell communication to extensive systemic signalling, and involving various organs and organ systems, including the central nervous system. As such, the discovery that differential microbial composition is associated with alterations in behaviour and cognition has significantly contributed to establishing the microbiota-gut-brain axis as an extension of the well-accepted gut-brain axis concept. Many efforts have been focused on delineating a role for this axis in health and disease, ranging from stress-related disorders such as depression, anxiety and irritable bowel syndrome to neurodevelopmental disorders such as autism. There is also a growing appreciation of the role of epigenetic mechanisms in shaping brain and behaviour. However, the role of epigenetics in informing host-microbe interactions has received little attention to date. This is despite the fact that there are many plausible routes of interaction between epigenetic mechanisms and the host-microbiota dialogue. From this new perspective we put forward novel, yet testable, hypotheses. Firstly, we suggest that gut-microbial products can affect chromatin plasticity within their host's brain that in turn leads to changes in neuronal transcription and eventually alters host behaviour. Secondly, we argue that the microbiota is an important mediator of gene-environment interactions. Finally, we reason that the microbiota itself may be viewed as an epigenetic entity. In conclusion, the fields of (neuro)epigenetics and microbiology are converging at many levels and more interdisciplinary studies are necessary to unravel the full range of this interaction.
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