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Vieira MFM, Hernandez G, Zhong Q, Arbesú M, Veloso T, Gomes T, Martins ML, Monteiro H, Frazão C, Frankel G, Zanzoni A, Cordeiro TN. The pathogen-encoded signalling receptor Tir exploits host-like intrinsic disorder for infection. Commun Biol 2024; 7:179. [PMID: 38351154 PMCID: PMC10864410 DOI: 10.1038/s42003-024-05856-9] [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: 11/23/2022] [Accepted: 01/26/2024] [Indexed: 02/16/2024] Open
Abstract
The translocated intimin receptor (Tir) is an essential type III secretion system (T3SS) effector of attaching and effacing pathogens contributing to the global foodborne disease burden. Tir acts as a cell-surface receptor in host cells, rewiring intracellular processes by targeting multiple host proteins. We investigated the molecular basis for Tir's binding diversity in signalling, finding that Tir is a disordered protein with host-like binding motifs. Unexpectedly, also are several other T3SS effectors. By an integrative approach, we reveal that Tir dimerises via an antiparallel OB-fold within a highly disordered N-terminal cytosolic domain. Also, it has a long disordered C-terminal cytosolic domain partially structured at host-like motifs that bind lipids. Membrane affinity depends on lipid composition and phosphorylation, highlighting a previously unrecognised host interaction impacting Tir-induced actin polymerisation and cell death. Furthermore, multi-site tyrosine phosphorylation enables Tir to engage host SH2 domains in a multivalent fuzzy complex, consistent with Tir's scaffolding role and binding promiscuity. Our findings provide insights into the intracellular Tir domains, highlighting the ability of T3SS effectors to exploit host-like protein disorder as a strategy for host evasion.
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Affiliation(s)
- Marta F M Vieira
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, Portugal
| | - Guillem Hernandez
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, Portugal
| | - Qiyun Zhong
- Department of Life Sciences, Imperial College London, South Kensington Campus, London, UK
| | - Miguel Arbesú
- Department of NMR-supported Structural Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
- InstaDeep Ltd, 5 Merchant Square, London, UK
| | - Tiago Veloso
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, Portugal
| | - Tiago Gomes
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, Portugal
| | - Maria L Martins
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, Portugal
| | - Hugo Monteiro
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, Portugal
| | - Carlos Frazão
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, Portugal
| | - Gad Frankel
- Department of Life Sciences, Imperial College London, South Kensington Campus, London, UK
| | - Andreas Zanzoni
- Aix-Marseille Université, Inserm, TAGC, UMR_S1090, Marseille, France
| | - Tiago N Cordeiro
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, Portugal.
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Compensatory Protection of Thioredoxin-Deficient Cells from Etoposide-Induced Cell Death by Selenoprotein W via Interaction with 14-3-3. Int J Mol Sci 2021; 22:ijms221910338. [PMID: 34638679 PMCID: PMC8508763 DOI: 10.3390/ijms221910338] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 09/20/2021] [Accepted: 09/22/2021] [Indexed: 12/26/2022] Open
Abstract
Selenoprotein W (SELENOW) is a 9.6 kDa protein containing selenocysteine (Sec, U) in a conserved Cys-X-X-Sec (CXXU) motif. Previously, we reported that SELENOW regulates various cellular processes by interacting with 14-3-3β at the U of the CXXU motif. Thioredoxin (Trx) is a small protein that plays a key role in the cellular redox regulatory system. The CXXC motif of Trx is critical for redox regulation. Recently, an interaction between Trx1 and 14-3-3 has been predicted. However, the binding mechanism and its biological effects remain unknown. In this study, we found that Trx1 interacted with 14-3-3β at the Cys32 residue in the CXXC motif, and SELENOW and Trx1 were bound at Cys191 residue of 14-3-3β. In vitro binding assays showed that SELENOW and Trx1 competed for interaction with 14-3-3β. Compared to control cells, Trx1-deficient cells and SELENOW-deficient cells showed increased levels of both the subG1 population and poly (ADP-ribose) polymerase (PARP) cleavage by etoposide treatment. Moreover, Akt phosphorylation of Ser473 was reduced in Trx1-deficient cells and was recovered by overexpression of SELENOW. These results indicate that SELENOW can protect Trx1-deficient cells from etoposide-induced cell death through its interaction with 14-3-3β.
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Abdrabou A, Brandwein D, Liu C, Wang Z. Rac1 S71 Mediates the Interaction between Rac1 and 14-3-3 Proteins. Cells 2019; 8:E1006. [PMID: 31480268 PMCID: PMC6770128 DOI: 10.3390/cells8091006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 08/23/2019] [Accepted: 08/26/2019] [Indexed: 02/07/2023] Open
Abstract
Both 14-3-3 proteins (14-3-3s) and Rho proteins regulate cytoskeleton remodeling and cell migration, which suggests a possible interaction between the signaling pathways regulated by these two groups of proteins. Indeed, more and more emerging evidence indicates the mutual regulation of these two signaling pathways. However, all of the data regarding the interaction between Rac1 signaling pathways and 14-3-3 signaling pathways are through either the upstream regulators or downstream substrates. It is not clear if Rac1 could interact with 14-3-3s directly. It is interesting to notice that the Rac1 sequence 68RPLSYP73 is likely a 14-3-3 protein binding motif following the phosphorylation of S71 by Akt. Thus, we hypothesize that Rac1 directly interacts with 14-3-3s. We tested this hypothesis in this research. By using mutagenesis, co-immunoprecipitation (co-IP), Rac1 activity assay, immunoblotting, and indirect immunofluorescence, we demonstrate that 14-3-3s interact with Rac1. This interaction is mediated by Rac1 S71 in both phosphorylation-dependent and -independent manners, but the phosphorylation-dependent interaction is much stronger. Epidermal growth factor (EGF) strongly stimulates the phosphorylation of Rac1 S71 and the interaction between 14-3-3s and Rac1. Mutating S71 to A completely abolishes both phosphorylation-dependent and -independent interactions between 14-3-3s and Rac1. The interaction between 14-3-3s and Rac1 mostly serve to regulate the activity and subcellular localization of Rac1. Among the seven 14-3-3 isoforms, 14-3-3η, -σ, and -θ showed interactions with Rac1 in both Cos-7 and HEK 293 cells. 14-3-3γ also binds to Rac1 in HEK 293 cells, but not in Cos-7 cells. We conclude that 14-3-3s interact with Rac1. This interaction is mediated by Rac1 S71 in both phosphorylation-dependent and -independent manners. The interaction between 14-3-3 and Rac1 mostly serves to regulate the activity and subcellular localization of Rac1. Among the seven 14-3-3 isoforms, 14-3-3η, -γ, -σ, and -θ interact with Rac1.
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Affiliation(s)
- Abdalla Abdrabou
- Department of Medical Genetics, and Signal Transduction Research Group, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Daniel Brandwein
- Department of Medical Genetics, and Signal Transduction Research Group, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Changyu Liu
- Department of Medical Genetics, and Signal Transduction Research Group, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Zhixiang Wang
- Department of Medical Genetics, and Signal Transduction Research Group, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
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4
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Differential abundance and transcription of 14-3-3 proteins during vegetative growth and sexual reproduction in budding yeast. Sci Rep 2018; 8:2145. [PMID: 29391437 PMCID: PMC5794856 DOI: 10.1038/s41598-018-20284-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 01/16/2018] [Indexed: 12/02/2022] Open
Abstract
14-3-3 is a family of relatively low molecular weight, acidic, dimeric proteins, conserved from yeast to metazoans including humans. Apart from their role in diverse cellular processes, these proteins are also known for their role in several clinical implications. Present proteomic and biochemical comparison showed increased abundance and differential phosphorylation of these proteins in meiotic cells. Double deletion of bmh1−/−bmh2−/− leads to complete absence of sporulation with cells arrested at G1/S phase while further incubation of cells in sporulating media leads to cell death. In silico analysis showed the presence of 14-3-3 interacting motifs in bonafide members of kinetochore complex (KC) and spindle pole body (SPB), while present cell biological data pointed towards the possible role of yeast Bmh1/2 in regulating the behaviour of KC and SPB. We further showed the involvement of 14-3-3 in segregation of genetic material and expression of human 14-3-3β/α was able to complement the function of endogenous 14-3-3 protein even in the complex cellular process like meiosis. Our present data also established haplosufficient nature of BMH1/2. We further showed that proteins synthesized during mitotic growth enter meiotic cells without de novo synthesis except for meiotic-specific proteins required for induction and meiotic progression in Saccharomyces cerevisiae.
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Shenoy AR, Furniss RCD, Goddard PJ, Clements A. Modulation of Host Cell Processes by T3SS Effectors. Curr Top Microbiol Immunol 2018; 416:73-115. [PMID: 30178263 DOI: 10.1007/82_2018_106] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Two of the enteric Escherichia coli pathotypes-enteropathogenic E. coli (EPEC) and enterohaemorrhagic E. coli (EHEC)-have a conserved type 3 secretion system which is essential for virulence. The T3SS is used to translocate between 25 and 50 bacterial proteins directly into the host cytosol where they manipulate a variety of host cell processes to establish a successful infection. In this chapter, we discuss effectors from EPEC/EHEC in the context of the host proteins and processes that they target-the actin cytoskeleton, small guanosine triphosphatases and innate immune signalling pathways that regulate inflammation and cell death. Many of these translocated proteins have been extensively characterised, which has helped obtain insights into the mechanisms of pathogenesis of these bacteria and also understand the host pathways they target in more detail. With increasing knowledge of the positive and negative regulation of host signalling pathways by different effectors, a future challenge is to investigate how the specific effector repertoire of each strain cooperates over the course of an infection.
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Affiliation(s)
- Avinash R Shenoy
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, Armstrong Road, SW7 2AZ, London, UK
| | - R Christopher D Furniss
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, Armstrong Road, SW7 2AZ, London, UK
| | - Philippa J Goddard
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, Armstrong Road, SW7 2AZ, London, UK
| | - Abigail Clements
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, Armstrong Road, SW7 2AZ, London, UK.
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6
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Kumar R. An account of fungal 14-3-3 proteins. Eur J Cell Biol 2017; 96:206-217. [PMID: 28258766 DOI: 10.1016/j.ejcb.2017.02.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Revised: 02/21/2017] [Accepted: 02/21/2017] [Indexed: 01/09/2023] Open
Abstract
14-3-3s are a group of relatively low molecular weight, acidic, dimeric, protein(s) conserved from single-celled yeast to multicellular vertebrates including humans. Despite lacking catalytic activity, these proteins have been shown to be involved in multiple cellular processes. Apart from their role in normal cellular physiology, recently these proteins have been implicated in various medical consequences. In this present review, fungal 14-3-3 protein localization, interactions, transcription, regulation, their role in the diverse cellular process including DNA duplication, cell cycle, protein trafficking or secretion, apoptosis, autophagy, cell viability under stress, gene expression, spindle positioning, role in carbon metabolism have been discussed. In the end, I also highlighted various roles of yeasts 14-3-3 proteins in tabular form. Thus this review with primary emphasis on yeast will help in appreciating the significance of 14-3-3 proteins in cell physiology.
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Affiliation(s)
- Ravinder Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, Maharashtra, India.
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7
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The Locus of Enterocyte Effacement and Associated Virulence Factors of Enterohemorrhagic Escherichia coli. Microbiol Spectr 2016; 2:EHEC-0007-2013. [PMID: 26104209 DOI: 10.1128/microbiolspec.ehec-0007-2013] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A subset of Shiga toxin-producing Escherichia coli strains, termed enterohemorrhagic E. coli (EHEC), is defined in part by the ability to produce attaching and effacing (A/E) lesions on intestinal epithelia. Such lesions are characterized by intimate bacterial attachment to the apical surface of enterocytes, cytoskeletal rearrangements beneath adherent bacteria, and destruction of proximal microvilli. A/E lesion formation requires the locus of enterocyte effacement (LEE), which encodes a Type III secretion system that injects bacterial proteins into host cells. The translocated proteins, termed effectors, subvert a plethora of cellular pathways to the benefit of the pathogen, for example, by recruiting cytoskeletal proteins, disrupting epithelial barrier integrity, and interfering with the induction of inflammation, phagocytosis, and apoptosis. The LEE and selected effectors play pivotal roles in intestinal persistence and virulence of EHEC, and it is becoming clear that effectors may act in redundant, synergistic, and antagonistic ways during infection. Vaccines that target the function of the Type III secretion system limit colonization of reservoir hosts by EHEC and may thus aid control of zoonotic infections. Here we review the features and functions of the LEE-encoded Type III secretion system and associated effectors of E. coli O157:H7 and other Shiga toxin-producing E. coli strains.
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8
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Identification of a redox-modulatory interaction between selenoprotein W and 14-3-3 protein. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:10-8. [DOI: 10.1016/j.bbamcr.2015.10.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 09/18/2015] [Accepted: 10/10/2015] [Indexed: 11/20/2022]
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9
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Stradal TEB, Costa SCP. Type III Secreted Virulence Factors Manipulating Signaling to Actin Dynamics. Curr Top Microbiol Immunol 2016; 399:175-199. [PMID: 27744505 DOI: 10.1007/82_2016_35] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A key aspect of bacterial pathogenesis is the colonization and persistence within the host and, later on, its dissemination to new niches. During evolution, bacteria developed a myriad of virulence mechanisms to usurp the host's sophisticated defense mechanisms in order to establish their colonization niche. Elucidation of the highly dynamic and complex interactions between host and pathogens remains an important field of study. Here, we highlight the conserved manipulation of the actin cytoskeleton by some Gram-negative gastrointestinal pathogens, addressing the role of type III secreted bacterial GEFs at the different steps of pathogenesis. As a final topic, we review cytoskeleton dynamics induced by EPEC/EHEC strains for pedestal formation.
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Affiliation(s)
- Theresia E B Stradal
- Department of Cell Biology, Helmholtz Centre for Infection Research, Inhoffenstr. 7, 38124, Baunschweig, Germany.
| | - Sonia C P Costa
- Department of Cell Biology, Helmholtz Centre for Infection Research, Inhoffenstr. 7, 38124, Baunschweig, Germany
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10
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Blasche S, Arens S, Ceol A, Siszler G, Schmidt MA, Häuser R, Schwarz F, Wuchty S, Aloy P, Uetz P, Stradal T, Koegl M. The EHEC-host interactome reveals novel targets for the translocated intimin receptor. Sci Rep 2014; 4:7531. [PMID: 25519916 PMCID: PMC4269881 DOI: 10.1038/srep07531] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 11/21/2014] [Indexed: 12/20/2022] Open
Abstract
Enterohemorrhagic E. coli (EHEC) manipulate their human host through at least 39 effector proteins which hijack host processes through direct protein-protein interactions (PPIs). To identify their protein targets in the host cells, we performed yeast two-hybrid screens, allowing us to find 48 high-confidence protein-protein interactions between 15 EHEC effectors and 47 human host proteins. In comparison to other bacteria and viruses we found that EHEC effectors bind more frequently to hub proteins as well as to proteins that participate in a higher number of protein complexes. The data set includes six new interactions that involve the translocated intimin receptor (TIR), namely HPCAL1, HPCAL4, NCALD, ARRB1, PDE6D, and STK16. We compared these TIR interactions in EHEC and enteropathogenic E. coli (EPEC) and found that five interactions were conserved. Notably, the conserved interactions included those of serine/threonine kinase 16 (STK16), hippocalcin-like 1 (HPCAL1) as well as neurocalcin-delta (NCALD). These proteins co-localize with the infection sites of EPEC. Furthermore, our results suggest putative functions of poorly characterized effectors (EspJ, EspY1). In particular, we observed that EspJ is connected to the microtubule system while EspY1 appears to be involved in apoptosis/cell cycle regulation.
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Affiliation(s)
- Sonja Blasche
- Genomics and Proteomics Core Facilities, German Cancer Research Center, Im Neuenheimer Feld 580, 69120 Heidelberg, Germany
| | - Stefan Arens
- Institute of Molecular Cell Biology, University of Münster, Schlossplatz 5, D-48149 Münster
| | - Arnaud Ceol
- 1] Joint IRB-BSC Program in Computational Biology, Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain [2] Center for Genomic Science of IIT@SEMM, Fondazione Istituto Italiano di Tecnologia (IIT), Via Adamello 16, 20139 Milan - Italy
| | - Gabriella Siszler
- Genomics and Proteomics Core Facilities, German Cancer Research Center, Im Neuenheimer Feld 580, 69120 Heidelberg, Germany
| | - M Alexander Schmidt
- Institute of Infectiology, ZMBE, University of Münster, Von-Esmarch-Str. 56, D-48149 Münster
| | - Roman Häuser
- Genomics and Proteomics Core Facilities, German Cancer Research Center, Im Neuenheimer Feld 580, 69120 Heidelberg, Germany
| | - Frank Schwarz
- Genomics and Proteomics Core Facilities, German Cancer Research Center, Im Neuenheimer Feld 580, 69120 Heidelberg, Germany
| | - Stefan Wuchty
- 1] Dept. of Computer Science, Univ. of Miami, 1365 Memorial Drive, Coral Gables, FL 33146, USA [2] Center for Computational Science, Univ. of Miami, 1365 Memorial Drive, Coral Gables, FL 33146, USA
| | - Patrick Aloy
- 1] Joint IRB-BSC Program in Computational Biology, Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain [2] Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Peter Uetz
- Center for the Study of Biological Complexity, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Theresia Stradal
- 1] Institute of Molecular Cell Biology, University of Münster, Schlossplatz 5, D-48149 Münster [2] Helmholtz Centre for Infection Research, Inhoffenstrasse 7, D-38124 Braunschweig
| | - Manfred Koegl
- Genomics and Proteomics Core Facilities, German Cancer Research Center, Im Neuenheimer Feld 580, 69120 Heidelberg, Germany
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11
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da Silva JDF, de Oliveira HC, Marcos CM, da Silva RAM, da Costa TA, Calich VLG, Almeida AMF, Mendes-Giannini MJS. Paracoccidoides brasiliensis 30 kDa adhesin: identification as a 14-3-3 protein, cloning and subcellular localization in infection models. PLoS One 2013; 8:e62533. [PMID: 23638109 PMCID: PMC3640054 DOI: 10.1371/journal.pone.0062533] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 03/21/2013] [Indexed: 02/04/2023] Open
Abstract
Paracoccidoides brasiliensis adhesion to lung epithelial cells is considered an essential event for the establishment of infection and different proteins participate in this process. One of these proteins is a 30 kDa adhesin, pI 4.9 that was described as a laminin ligand in previous studies, and it was more highly expressed in more virulent P. brasiliensis isolates. This protein may contribute to the virulence of this important fungal pathogen. Using Edman degradation and mass spectrometry analysis, this 30 kDa adhesin was identified as a 14-3-3 protein. These proteins are a conserved group of small acidic proteins involved in a variety of processes in eukaryotic organisms. However, the exact function of these proteins in some processes remains unknown. Thus, the goal of the present study was to characterize the role of this protein during the interaction between the fungus and its host. To achieve this goal, we cloned, expressed the 14-3-3 protein in a heterologous system and determined its subcellular localization in in vitro and in vivo infection models. Immunocytochemical analysis revealed the ubiquitous distribution of this protein in the yeast form of P. brasiliensis, with some concentration in the cytoplasm. Additionally, this 14-3-3 protein was also present in P. brasiliensis cells at the sites of infection in C57BL/6 mice intratracheally infected with P. brasiliensis yeast cells for 72 h (acute infections) and 30 days (chronic infection). An apparent increase in the levels of the 14-3-3 protein in the cell wall of the fungus was also noted during the interaction between P. brasiliensis and A549 cells, suggesting that this protein may be involved in host-parasite interactions, since inhibition assays with the protein and this antibody decreased P. brasiliensis adhesion to A549 epithelial cells. Our data may lead to a better understanding of P. brasiliensis interactions with host tissues and paracoccidioidomycosis pathogenesis.
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Affiliation(s)
- Julhiany de Fatima da Silva
- Department of Clinical Analyses, Faculty of Pharmaceutical Sciences, São Paulo State University - University Estadual Paulista Araraquara, São Paulo, Brazil
| | - Haroldo César de Oliveira
- Department of Clinical Analyses, Faculty of Pharmaceutical Sciences, São Paulo State University - University Estadual Paulista Araraquara, São Paulo, Brazil
| | - Caroline Maria Marcos
- Department of Clinical Analyses, Faculty of Pharmaceutical Sciences, São Paulo State University - University Estadual Paulista Araraquara, São Paulo, Brazil
| | - Rosângela Aparecida Moraes da Silva
- Department of Clinical Analyses, Faculty of Pharmaceutical Sciences, São Paulo State University - University Estadual Paulista Araraquara, São Paulo, Brazil
| | - Tania Alves da Costa
- Department of Immunology, Biomedical Institute, São Paulo University, São Paulo, Brazil
| | | | - Ana Marisa Fusco Almeida
- Department of Clinical Analyses, Faculty of Pharmaceutical Sciences, São Paulo State University - University Estadual Paulista Araraquara, São Paulo, Brazil
| | - Maria José Soares Mendes-Giannini
- Department of Clinical Analyses, Faculty of Pharmaceutical Sciences, São Paulo State University - University Estadual Paulista Araraquara, São Paulo, Brazil
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Wong ARC, Pearson JS, Bright MD, Munera D, Robinson KS, Lee SF, Frankel G, Hartland EL. Enteropathogenic and enterohaemorrhagic Escherichia coli: even more subversive elements. Mol Microbiol 2011; 80:1420-38. [PMID: 21488979 DOI: 10.1111/j.1365-2958.2011.07661.x] [Citation(s) in RCA: 253] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Alexander R C Wong
- Centre for Molecular Microbiology and Infection, Division of Cell and Molecular Biology, Imperial College London, London SW7 2AZ, UK
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13
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Wessler S, Backert S. Abl family of tyrosine kinases and microbial pathogenesis. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2011; 286:271-300. [PMID: 21199784 DOI: 10.1016/b978-0-12-385859-7.00006-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Abl nonreceptor tyrosine kinases are activated by multiple stimuli and regulate cytoskeletal reorganization, cell proliferation, survival, and stress responses. Several downstream pathways have direct impact on physiological processes, including development and maintenance of the nervous and immune systems and epithelial morphogenesis. Recent studies also indicated that numerous viral and bacterial pathogens highjack Abl signaling for different purposes. Abl kinases are activated to reorganize the host actin cytoskeleton and promote the direct tyrosine phosphorylation of viral surface proteins and injected bacterial type-III and type-IV effector molecules. However, Abl kinases also play other roles in infectious processes of bacteria, viruses, and prions. These activities have crucial impact on microbial invasion and release from host cells, actin-based motility, pedestal formation, as well as cell-cell dissociation involved in epithelial barrier disruption and other responses. Thus, Abl kinases exhibit important functions in pathological signaling during microbial infections. Here, we discuss the different signaling pathways activated by pathogens and highlight possible therapeutic intervention strategies.
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Affiliation(s)
- Silja Wessler
- Department of Molecular Biology, Division of Microbiology, Paris-Lodron University of Salzburg, Billrothstrasse, Salzburg, Austria
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14
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Backert S, Kenny B, Gerhard R, Tegtmeyer N, Brandt S. PKA-mediated phosphorylation of EPEC-Tir at serine residues 434 and 463: A novel pathway in regulating Rac1 GTPase function. Cell Signal 2010; 21:462-9. [PMID: 19091303 DOI: 10.1016/j.cellsig.2008.11.013] [Citation(s) in RCA: 166] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2008] [Accepted: 11/15/2008] [Indexed: 01/29/2023]
Abstract
Type-III or type-IV secretion systems of many Gram-negative bacterial pathogens inject effector proteins into host cells that modulate cellular functions in their favour. A preferred target of these effectors is the actin-cytoskeleton as shown by studies using the gastric pathogens Helicobacter pylori (H. pylori) and enteropathogenic Escherichia coli (EPEC). We recently developed a co-infection approach to study effector protein function and molecular mechanisms by which they highjack cellular signalling cascades. This is exemplified by our observation that EPEC profoundly blocks H. pylori-induced epithelial cell scattering and elongation, a disease-related event requiring the activity of small Rho GTPase Rac1. While this suppressive effect is dependent on the effector protein Tir and the outer-membrane protein Intimin, it unexpectedly revealed evidence for Tir-signalling independent of phosphorylation of Tir at tyrosine residues 454 and 474. Instead, our studies revealed a previously unidentified function for protein kinase A (PKA)-mediated phosphorylation of Tir at serine residues 434 and 463. We demonstrated that EPEC infection activates PKA for Tir phosphorylation. Activated PKA then phosphorylates Rac1 at its serine residue 71 associated with reduced GTP-load and inhibited cell elongation. Phosphorylation of Rho GTPases such as Rac1 might be an interesting novel strategy in microbial pathogenesis.
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Affiliation(s)
- Steffen Backert
- University College Dublin; School of Biomolecular and Biomedical Sciences; Dublin, Ireland
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Backert S, Kenny B, Gerhard R, Tegtmeyer N, Brandt S, Li DB, Li Y, Che GW. PKA-mediated phosphorylation of EPEC-Tir at serine residues 434 and 463: A novel pathway in regulating Rac1 GTPase function. Gut Microbes 2010; 1:94-99. [PMID: 21326916 PMCID: PMC3023586 DOI: 10.4161/gmic.1.2.11437] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 01/11/2010] [Accepted: 02/08/2010] [Indexed: 02/03/2023] Open
Abstract
Type-III or type-IV secretion systems of many Gram-negative bacterial pathogens inject effector proteins into host cells that modulate cellular functions in their favour. A preferred target of these effectors is the actin-cytoskeleton as shown by studies using the gastric pathogens Helicobacter pylori (H. pylori) and enteropathogenic Escherichia coli (EPEC). We recently developed a co-infection approach to study effector protein function and molecular mechanisms by which they highjack cellular signalling cascades. This is exemplified by our observation that EPEC profoundly blocks H. pylori-induced epithelial cell scattering and elongation, a disease-related event requiring the activity of small Rho GTPase Rac1. While this suppressive effect is dependent on the effector protein Tir and the outer-membrane protein Intimin, it unexpectedly revealed evidence for Tir-signalling independent of phosphorylation of Tir at tyrosine residues 454 and 474. Instead, our studies revealed a previously unidentified function for protein kinase A (PKA)-mediated phosphorylation of Tir at serine residues 434 and 463. We demonstrated that EPEC infection activates PKA for Tir phosphorylation. Activated PKA then phosphorylates Rac1 at its serine residue 71 associated with reduced GTP-load and inhibited cell elongation. Phosphorylation of Rho GTPases such as Rac1 might be an interesting novel strategy in microbial pathogenesis.
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Affiliation(s)
- Steffen Backert
- University College Dublin; School of Biomolecular and Biomedical Sciences; Dublin, Ireland
| | - Brendan Kenny
- Institute for Cell and Molecular Biosciences; Medical School; University of Newcastle; Newcastle, UK
| | - Ralf Gerhard
- Institute for Toxicology; Medical School Hannover; Hannover, Germany
| | - Nicole Tegtmeyer
- University College Dublin; School of Biomolecular and Biomedical Sciences; Dublin, Ireland
| | - Sabine Brandt
- Department of Medical Microbiology; Otto von Guericke University; Magdeburg, Germany
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16
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Nieto-Pelegrin E, Martinez-Quiles N. Distinct phosphorylation requirements regulate cortactin activation by TirEPEC and its binding to N-WASP. Cell Commun Signal 2009; 7:11. [PMID: 19419567 PMCID: PMC2686683 DOI: 10.1186/1478-811x-7-11] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2009] [Accepted: 05/06/2009] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND Cortactin activates the actin-related 2/3 (Arp2/3) complex promoting actin polymerization to remodel cell architecture in multiple processes (e.g. cell migration, membrane trafficking, invadopodia formation etc.). Moreover, it was called the Achilles' heel of the actin cytoskeleton because many pathogens hijack signals that converge on this oncogenic scaffolding protein. Cortactin is able to modulate N-WASP activation in vitro in a phosphorylation-dependent fashion. Thus Erk-phosphorylated cortactin is efficient in activating N-WASP through its SH3 domain, while Src-phosphorylated cortactin is not. This could represent a switch on/off mechanism controlling the coordinated action of both nucleator promoting factors (NPFs). Pedestal formation by enteropathogenic Escherichia coli (EPEC) requires N-WASP activation. N-WASP is recruited by the cell adapter Nck which binds a major tyrosine-phosphorylated site of a bacterial injected effector, Tir (translocated intimin receptor). Tir-Nck-N-WASP axis defines the current major pathway to actin polymerization on pedestals. In addition, it was recently reported that EPEC induces tyrosine phosphorylation of cortactin. RESULTS Here we demonstrate that cortactin phosphorylation is absent on N-WASP deficient cells, but is recovered by re-expression of N-WASP. We used purified recombinant cortactin and Tir proteins to demonstrate a direct interaction of both that promoted Arp2/3 complex-mediated actin polymerization in vitro, independently of cortactin phosphorylation. CONCLUSION We propose that cortactin binds Tir through its N-terminal part in a tyrosine and serine phosphorylation independent manner while SH3 domain binding and activation of N-WASP is regulated by tyrosine and serine mediated phosphorylation of cortactin. Therefore cortactin could act on Tir-Nck-N-WASP pathway and control a possible cycling activity of N-WASP underlying pedestal formation.
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Affiliation(s)
- Elvira Nieto-Pelegrin
- Microbiología II, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain.
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17
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Brandt S, Kenny B, Rohde M, Martinez-Quiles N, Backert S. Dual infection system identifies a crucial role for PKA-mediated serine phosphorylation of the EPEC-Tir-injected effector protein in regulating Rac1 function. Cell Microbiol 2009; 11:1254-71. [PMID: 19438518 DOI: 10.1111/j.1462-5822.2009.01330.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Many Gram-negative pathogenic bacteria possess type-III or type-IV secretion systems to inject 'effector' proteins directly into host cells to modulate cellular processes in their favour. A common target is the actin-cytoskeleton linked to the delivery of a single (CagA) effector by Helicobacter pylori and multiple effectors by enteropathogenic Escherichia coli (EPEC) respectively. Here we report co-infection as a powerful strategy for defining effector protein function and mechanisms by which they modulate cellular responses. This is exemplified by our finding that EPEC inhibits H. pylori-induced AGS cell elongation, a disease-related event linked to Rac1 activation. While this inhibitory process is dependent on the translocated Intimin receptor, Tir, and the outer-membrane protein, Intimin, it unexpectedly revealed evidence for Tir signalling independent of Intimin interaction and tyrosine phosphorylation of Tir. Furthermore, the work defined a long awaited role for protein kinase A (PKA)-mediated phosphorylation of Tir at serine-434 and serine-463. Our data are consistent with a model whereby EPEC activates PKA for Tir phosphorylation. Activated PKA then phosphorylates Rac1 at serine-71 associated with reduced GTP-load and inhibited cell elongation. Thus, the co-infection approach is a powerful strategy for defining novel effector function with important implications for characterizing mechanisms and regulatory signalling pathways in bacterial pathogenesis.
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Affiliation(s)
- Sabine Brandt
- Department of Medical Microbiology, Otto von Guericke University, Leipziger Str. 44, D-39120 Magdeburg, Germany
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18
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Huett A, Leong JM, Podolsky DK, Xavier RJ. The cytoskeletal scaffold Shank3 is recruited to pathogen-induced actin rearrangements. Exp Cell Res 2009; 315:2001-11. [PMID: 19371741 DOI: 10.1016/j.yexcr.2009.04.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2008] [Revised: 03/14/2009] [Accepted: 04/06/2009] [Indexed: 01/25/2023]
Abstract
The common gastrointestinal pathogens enteropathogenic Escherichia coli (EPEC) and Salmonella typhimurium both reorganize the gut epithelial cell actin cytoskeleton to mediate pathogenesis, utilizing mimicry of the host signaling apparatus. The PDZ domain-containing protein Shank3, is a large cytoskeletal scaffold protein with known functions in neuronal morphology and synaptic signaling, and is also capable of acting as a scaffolding adaptor during Ret tyrosine kinase signaling in epithelial cells. Using immunofluorescent and functional RNA-interference approaches we show that Shank3 is present in both EPEC- and S. typhimurium-induced actin rearrangements and is required for optimal EPEC pedestal formation. We propose that Shank3 is one of a number of host synaptic proteins likely to play key roles in bacteria-host interactions.
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Affiliation(s)
- Alan Huett
- Gastrointestinal Unit, Center for the Study of Inflammatory Bowel Diseases, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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19
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Brown MD, Bry L, Li Z, Sacks DB. Actin pedestal formation by enteropathogenic Escherichia coli is regulated by IQGAP1, calcium, and calmodulin. J Biol Chem 2008; 283:35212-22. [PMID: 18809683 DOI: 10.1074/jbc.m803477200] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
During infection, enteropathogenic Escherichia coli (EPEC) injects effector proteins into the host cell to manipulate the actin cytoskeleton and promote formation of actin pedestals. IQGAP1 is a multidomain protein that participates in numerous cellular functions, including Rac1/Cdc42 and Ca(2+)/calmodulin signaling and actin polymerization. Here we report that IQGAP1, Ca(2+), and calmodulin modulate actin pedestal formation by EPEC. Infection with EPEC promotes both the interaction of IQGAP1 with calmodulin and the localization of IQGAP1 and calmodulin to actin pedestals while reducing the interaction of IQGAP1 with Rac1 and Cdc42. IQGAP1-null fibroblasts display a reduced polymerization of actin in response to EPEC. In addition, antagonism of calmodulin or chelation of intracellular Ca(2+) reduces EPEC-dependent actin polymerization. Furthermore, IQGAP1 specifically interacts with Tir in vitro and in cells. Together these data identify IQGAP1, Ca(2+), and calmodulin as a novel signaling complex regulating actin pedestal formation by EPEC.
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Affiliation(s)
- Matthew D Brown
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Thorn 530, Boston, Massachusetts 02115, USA
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20
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Backert S, Feller SM, Wessler S. Emerging roles of Abl family tyrosine kinases in microbial pathogenesis. Trends Biochem Sci 2008; 33:80-90. [DOI: 10.1016/j.tibs.2007.10.006] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2007] [Revised: 10/15/2007] [Accepted: 10/19/2007] [Indexed: 01/04/2023]
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21
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Thomas NA, Deng W, Baker N, Puente J, Finlay BB. Hierarchical Delivery of an Essential Host Colonization Factor in Enteropathogenic Escherichia coli. J Biol Chem 2007; 282:29634-45. [PMID: 17681945 DOI: 10.1074/jbc.m706019200] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Many significant bacterial pathogens use a type III secretion system to inject effector proteins into host cells to disrupt specific cellular functions, enabling disease progression. The injection of these effectors into host cells is often dependent on dedicated chaperones within the bacterial cell. In this report, we demonstrate that the enteropathogenic Escherichia coli (EPEC) chaperone CesT interacts with a variety of known and putative type III effector proteins. Using pull-down and secretion assays, a degenerate CesT binding domain was identified within multiple type III effectors. Domain exchange experiments between selected type III effector proteins revealed a modular nature for the CesT binding domain, as demonstrated by secretion, chaperone binding, and infection assays. The CesT-interacting type III effector Tir, which is crucial for in vivo intestinal colonization, had to be expressed and secreted for efficient secretion of other type III effectors. In contrast, the absence of other CesT-interacting type III effectors did not abrogate effector secretion, indicating an unexpected hierarchy with respect to Tir for type III effector delivery. Coordinating the expression of other type III effectors with cesT in the absence of tir partially restored total type III effector secretion, thereby implicating CesT in secretion events. Collectively, the results suggest a coordinated mechanism involving both Tir and CesT for type III effector injection into host cells.
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Affiliation(s)
- Nikhil A Thomas
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4.
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22
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Ottmann C, Yasmin L, Weyand M, Veesenmeyer JL, Diaz MH, Palmer RH, Francis MS, Hauser AR, Wittinghofer A, Hallberg B. Phosphorylation-independent interaction between 14-3-3 and exoenzyme S: from structure to pathogenesis. EMBO J 2007; 26:902-13. [PMID: 17235285 PMCID: PMC1794388 DOI: 10.1038/sj.emboj.7601530] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2006] [Accepted: 12/04/2006] [Indexed: 01/04/2023] Open
Abstract
14-3-3 proteins are phosphoserine/phosphothreonine-recognizing adapter proteins that regulate the activity of a vast array of targets. There are also examples of 14-3-3 proteins binding their targets via unphosphorylated motifs. Here we present a structural and biological investigation of the phosphorylation-independent interaction between 14-3-3 and exoenzyme S (ExoS), an ADP-ribosyltransferase toxin of Pseudomonas aeruginosa. ExoS binds to 14-3-3 in a novel binding mode mostly relying on hydrophobic contacts. The 1.5 A crystal structure is supported by cytotoxicity analysis, which reveals that substitution of the corresponding hydrophobic residues significantly weakens the ability of ExoS to modify the endogenous targets RAS/RAP1 and to induce cell death. Furthermore, mutation of key residues within the ExoS binding site for 14-3-3 impairs virulence in a mouse pneumonia model. In conclusion, we show that ExoS binds 14-3-3 in a novel reversed orientation that is primarily dependent on hydrophobic residues. This interaction is phosphorylation independent and is required for the function of ExoS.
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Affiliation(s)
- Christian Ottmann
- Department of Structural Biology, Max-Planck-Institute for Molecular Physiology, Dortmund, Germany
- Chemical Genomics Centre, Dortmund, Germany
| | - Lubna Yasmin
- Department of Medical Biosciences/Pathology, Umeå University, Umeå, Sweden
| | - Michael Weyand
- Department of Structural Biology, Max-Planck-Institute for Molecular Physiology, Dortmund, Germany
| | - Jeffrey L Veesenmeyer
- Departments of Microbiology/Immunology and Medicine, Northwestern University, Chicago, IL, USA
| | - Maureen H Diaz
- Departments of Microbiology/Immunology and Medicine, Northwestern University, Chicago, IL, USA
| | - Ruth H Palmer
- Umeå Center for Molecular Pathogenesis, Umeå University, Umeå, Sweden
| | | | - Alan R Hauser
- Departments of Microbiology/Immunology and Medicine, Northwestern University, Chicago, IL, USA
| | - Alfred Wittinghofer
- Department of Structural Biology, Max-Planck-Institute for Molecular Physiology, Dortmund, Germany
| | - Bengt Hallberg
- Department of Medical Biosciences/Pathology, Umeå University, Umeå, Sweden
- Department of Medical Biosciences/Pathology, Buil. 6M, Umeå University, Umeå 90187, Sweden. Tel.: +46 907 852 523; Fax: +46 907 852 829; E-mail:
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23
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Hayward RD, Leong JM, Koronakis V, Campellone KG. Exploiting pathogenic Escherichia coli to model transmembrane receptor signalling. Nat Rev Microbiol 2006; 4:358-70. [PMID: 16582930 DOI: 10.1038/nrmicro1391] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Many microbial pathogens manipulate the actin cytoskeleton of eukaryotic target cells to promote their internalization, intracellular motility and dissemination. Enteropathogenic and enterohaemorrhagic Escherichia coli, which both cause severe diarrhoeal disease, can adhere to mammalian intestinal cells and induce reorganization of the actin cytoskeleton into 'pedestal-like' pseudopods beneath the extracellular bacteria. As pedestal assembly is triggered by E. coli virulence factors that mimic several host cell-signalling components, such as transmembrane receptors, their cognate ligands and cytoplasmic adaptor proteins, it can serve as a powerful model system to study eukaryotic transmembrane signalling. Here, we consider the impact of recent data on our understanding of both E. coli pathogenesis and cell biology, and the rich prospects for exploiting these bacterial factors as versatile tools to probe cellular signalling pathways.
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Affiliation(s)
- Richard D Hayward
- University of Cambridge, Department of Pathology, Tennis Court Road, Cambridge CB2 1QP, UK
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24
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Caron E, Crepin VF, Simpson N, Knutton S, Garmendia J, Frankel G. Subversion of actin dynamics by EPEC and EHEC. Curr Opin Microbiol 2006; 9:40-5. [PMID: 16406772 DOI: 10.1016/j.mib.2005.12.008] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2005] [Accepted: 12/21/2005] [Indexed: 10/25/2022]
Abstract
During the course of infection, enteropathogenic and enterohaemorrhagic Escherichia coli (EPEC and EHEC, respectively) subvert the host cell signalling machinery and hijack the actin cytoskeleton to tighten their interaction with the gut epithelium, while avoiding phagocytosis by professional phagocytes. Much progress has been made recently in our understanding of how EPEC and EHEC regulate the pathways leading to local activation of two regulators of actin cytoskeleton dynamics, the Wiskott-Aldrich syndrome protein (N-WASP) and the Arp2/3 complex. A recent highlight is the unravelling of functions for effector proteins (particularly Tir, TccP, Map and EspG/EspG2) that are injected into the host cell by a type III secretion system.
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Affiliation(s)
- Emmanuelle Caron
- Centre for Molecular Microbiology and Infection, Division of Cell and Molecular Biology, Imperial College London, London SW7 2AZ, UK
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