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Sánchez-Alba L, Borràs-Gas H, Huang G, Varejão N, Reverter D. Structural diversity of the CE-clan proteases in bacteria to disarm host ubiquitin defenses. Trends Biochem Sci 2024:S0968-0004(24)00206-8. [PMID: 39343712 DOI: 10.1016/j.tibs.2024.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2024] [Revised: 08/23/2024] [Accepted: 09/06/2024] [Indexed: 10/01/2024]
Abstract
Ubiquitin (Ub) and ubiquitin-like (UbL) modifications are critical regulators of multiple cellular processes in eukaryotes. These modifications are dynamically controlled by proteases that balance conjugation and deconjugation. In eukaryotes, these proteases include deubiquitinases (DUBs), mostly belonging to the CA-clan of cysteine proteases, and ubiquitin-like proteases (ULPs), belonging to the CE-clan proteases. Intriguingly, infectious bacteria exploit the CE-clan protease fold to generate deubiquitinating activities to disarm the immune system and degradation defenses of the host during infection. In this review, we explore the substrate preferences encoded within the CE-clan proteases and the structural determinants in the protease fold behind its selectivity, in particular those from infectious bacteria and viruses. Understanding this protease family provides crucial insights into the molecular mechanisms underlying infection and transmission of pathogenic organisms.
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Affiliation(s)
- Lucía Sánchez-Alba
- Institute of Biotechnology and Biomedicine, Autonomous University of Barcelona, 08193 Bellaterra, Spain; Department of Biochemistry and Molecular Biology, Autonomous University of Barcelona, 08193 Bellaterra, Spain.
| | - Helena Borràs-Gas
- Institute of Biotechnology and Biomedicine, Autonomous University of Barcelona, 08193 Bellaterra, Spain; Department of Biochemistry and Molecular Biology, Autonomous University of Barcelona, 08193 Bellaterra, Spain
| | - Ge Huang
- Institute of Biotechnology and Biomedicine, Autonomous University of Barcelona, 08193 Bellaterra, Spain; Department of Biochemistry and Molecular Biology, Autonomous University of Barcelona, 08193 Bellaterra, Spain
| | - Nathalia Varejão
- Institute of Biotechnology and Biomedicine, Autonomous University of Barcelona, 08193 Bellaterra, Spain; Department of Biochemistry and Molecular Biology, Autonomous University of Barcelona, 08193 Bellaterra, Spain
| | - David Reverter
- Institute of Biotechnology and Biomedicine, Autonomous University of Barcelona, 08193 Bellaterra, Spain; Department of Biochemistry and Molecular Biology, Autonomous University of Barcelona, 08193 Bellaterra, Spain.
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Waltho A, Popp O, Lenz C, Pluska L, Lambert M, Dötsch V, Mertins P, Sommer T. K48- and K63-linked ubiquitin chain interactome reveals branch- and length-specific ubiquitin interactors. Life Sci Alliance 2024; 7:e202402740. [PMID: 38803224 PMCID: PMC11109483 DOI: 10.26508/lsa.202402740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 05/08/2024] [Accepted: 05/08/2024] [Indexed: 05/29/2024] Open
Abstract
The ubiquitin (Ub) code denotes the complex Ub architectures, including Ub chains of different lengths, linkage types, and linkage combinations, which enable ubiquitination to control a wide range of protein fates. Although many linkage-specific interactors have been described, how interactors are able to decode more complex architectures is not fully understood. We conducted a Ub interactor screen, in humans and yeast, using Ub chains of varying lengths, as well as homotypic and heterotypic branched chains of the two most abundant linkage types-lysine 48-linked (K48) and lysine 63-linked (K63) Ub. We identified some of the first K48/K63-linked branch-specific Ub interactors, including histone ADP-ribosyltransferase PARP10/ARTD10, E3 ligase UBR4, and huntingtin-interacting protein HIP1. Furthermore, we revealed the importance of chain length by identifying interactors with a preference for Ub3 over Ub2 chains, including Ub-directed endoprotease DDI2, autophagy receptor CCDC50, and p97 adaptor FAF1. Crucially, we compared datasets collected using two common deubiquitinase inhibitors-chloroacetamide and N-ethylmaleimide. This revealed inhibitor-dependent interactors, highlighting the importance of inhibitor consideration during pulldown studies. This dataset is a key resource for understanding how the Ub code is read.
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Affiliation(s)
- Anita Waltho
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
- Institute for Biology, Humboldt-University zu Berlin, Berlin, Germany
| | - Oliver Popp
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Christopher Lenz
- Institute for Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Frankfurt, Germany
| | - Lukas Pluska
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
- Institute for Biology, Humboldt-University zu Berlin, Berlin, Germany
| | - Mahil Lambert
- Institute for Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Frankfurt, Germany
| | - Volker Dötsch
- Institute for Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Frankfurt, Germany
| | - Philipp Mertins
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Thomas Sommer
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
- Institute for Biology, Humboldt-University zu Berlin, Berlin, Germany
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3
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Chen W, Ji G, Wu R, Fang C, Lu H. Mass spectrometry-based candidate substrate and site identification of PTM enzymes. Trends Analyt Chem 2023. [DOI: 10.1016/j.trac.2023.116991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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Shiromizu T, Yuge M, Kasahara K, Yamakawa D, Matsui T, Bessho Y, Inagaki M, Nishimura Y. Targeting E3 Ubiquitin Ligases and Deubiquitinases in Ciliopathy and Cancer. Int J Mol Sci 2020; 21:E5962. [PMID: 32825105 PMCID: PMC7504095 DOI: 10.3390/ijms21175962] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/16/2020] [Accepted: 08/17/2020] [Indexed: 12/17/2022] Open
Abstract
Cilia are antenna-like structures present in many vertebrate cells. These organelles detect extracellular cues, transduce signals into the cell, and play an essential role in ensuring correct cell proliferation, migration, and differentiation in a spatiotemporal manner. Not surprisingly, dysregulation of cilia can cause various diseases, including cancer and ciliopathies, which are complex disorders caused by mutations in genes regulating ciliary function. The structure and function of cilia are dynamically regulated through various mechanisms, among which E3 ubiquitin ligases and deubiquitinases play crucial roles. These enzymes regulate the degradation and stabilization of ciliary proteins through the ubiquitin-proteasome system. In this review, we briefly highlight the role of cilia in ciliopathy and cancer; describe the roles of E3 ubiquitin ligases and deubiquitinases in ciliogenesis, ciliopathy, and cancer; and highlight some of the E3 ubiquitin ligases and deubiquitinases that are potential therapeutic targets for these disorders.
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Affiliation(s)
- Takashi Shiromizu
- Department of Integrative Pharmacology, Graduate School of Medicine, Mie University, Tsu, Mie 514-8507, Japan; (T.S.); (M.Y.)
| | - Mizuki Yuge
- Department of Integrative Pharmacology, Graduate School of Medicine, Mie University, Tsu, Mie 514-8507, Japan; (T.S.); (M.Y.)
| | - Kousuke Kasahara
- Department of Physiology, Graduate School of Medicine, Mie University, Tsu, Mie 514-5807, Japan; (K.K.); (D.Y.); (M.I.)
| | - Daishi Yamakawa
- Department of Physiology, Graduate School of Medicine, Mie University, Tsu, Mie 514-5807, Japan; (K.K.); (D.Y.); (M.I.)
| | - Takaaki Matsui
- Gene Regulation Research, Division of Biological Sciences, Nara Institute of Science and Technology, Takayama, Nara 630-0192, Japan; (T.M.); (Y.B.)
| | - Yasumasa Bessho
- Gene Regulation Research, Division of Biological Sciences, Nara Institute of Science and Technology, Takayama, Nara 630-0192, Japan; (T.M.); (Y.B.)
| | - Masaki Inagaki
- Department of Physiology, Graduate School of Medicine, Mie University, Tsu, Mie 514-5807, Japan; (K.K.); (D.Y.); (M.I.)
| | - Yuhei Nishimura
- Department of Integrative Pharmacology, Graduate School of Medicine, Mie University, Tsu, Mie 514-8507, Japan; (T.S.); (M.Y.)
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Berglund J, Gjondrekaj R, Verney E, Maupin-Furlow JA, Edelmann MJ. Modification of the host ubiquitome by bacterial enzymes. Microbiol Res 2020; 235:126429. [PMID: 32109687 PMCID: PMC7369425 DOI: 10.1016/j.micres.2020.126429] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 02/03/2020] [Accepted: 02/09/2020] [Indexed: 12/14/2022]
Abstract
Attachment of ubiquitin molecules to protein substrates is a reversible post-translational modification (PTM), which occurs ubiquitously in eukaryotic cells and controls most cellular processes. As a consequence, ubiquitination is an attractive target of pathogen-encoded virulence factors. Pathogenic bacteria have evolved multiple mechanisms to hijack the host's ubiquitin system to their advantage. In this review, we discuss the bacteria-encoded E3 ligases and deubiquitinases translocated to the host for an addition or removal of eukaryotic ubiquitin modification, effectively hijacking the host's ubiquitination processes. We review bacterial enzymes homologous to host proteins in sequence and functions, as well as enzymes with novel mechanisms in ubiquitination, which have significant structural differences in comparison to the mammalian E3 ligases. Finally, we will also discuss examples of molecular "counter-weapons" - eukaryotic proteins, which counteract pathogen-encoded E3 ligases. The many examples of the pathogen effector molecules that catalyze eukaryotic ubiquitin modification bring to light the intricate pathways involved in the pathogenesis of some of the most virulent bacterial infections with human pathogens. The role of these effector molecules remains an essential determinant of bacterial virulence in terms of infection, invasion, and replication. A comprehensive understanding of the mechanisms dictating the mimicry employed by bacterial pathogens is of vital importance in developing new strategies for therapeutic approaches.
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Affiliation(s)
- Jennifer Berglund
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, 1355 Museum Drive, Gainesville, 32611-0700, FL USA
| | - Rafaela Gjondrekaj
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, 1355 Museum Drive, Gainesville, 32611-0700, FL USA
| | - Ellen Verney
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, 1355 Museum Drive, Gainesville, 32611-0700, FL USA
| | - Julie A Maupin-Furlow
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, 1355 Museum Drive, Gainesville, 32611-0700, FL USA
| | - Mariola J Edelmann
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, 1355 Museum Drive, Gainesville, 32611-0700, FL USA.
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Kliza K, Husnjak K. Resolving the Complexity of Ubiquitin Networks. Front Mol Biosci 2020; 7:21. [PMID: 32175328 PMCID: PMC7056813 DOI: 10.3389/fmolb.2020.00021] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 02/04/2020] [Indexed: 12/22/2022] Open
Abstract
Ubiquitination regulates nearly all cellular processes by coordinated activity of ubiquitin writers (E1, E2, and E3 enzymes), erasers (deubiquitinating enzymes) and readers (proteins that recognize ubiquitinated proteins by their ubiquitin-binding domains). By differentially modifying cellular proteome and by recognizing these ubiquitin modifications, ubiquitination machinery tightly regulates execution of specific cellular events in space and time. Dynamic and complex ubiquitin architecture, ranging from monoubiquitination, multiple monoubiquitination, eight different modes of homotypic and numerous types of heterogeneous polyubiquitin linkages, enables highly dynamic and complex regulation of cellular processes. We discuss available tools and approaches to study ubiquitin networks, including methods for the identification and quantification of ubiquitin-modified substrates, as well as approaches to quantify the length, abundance, linkage type and architecture of different ubiquitin chains. Furthermore, we also summarize the available approaches for the discovery of novel ubiquitin readers and ubiquitin-binding domains, as well as approaches to monitor and visualize activity of ubiquitin conjugation and deconjugation machineries. We also discuss benefits, drawbacks and limitations of available techniques, as well as what is still needed for detailed spatiotemporal dissection of cellular ubiquitination networks.
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Affiliation(s)
- Katarzyna Kliza
- Institute of Biochemistry II, Medical Faculty, Goethe University, Frankfurt, Germany
| | - Koraljka Husnjak
- Institute of Biochemistry II, Medical Faculty, Goethe University, Frankfurt, Germany
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Sannikova EP, Cheperegin SE, Kozlov DG. Ubiquitin-Specific E. coli Proteinase Does Not Require the Obligatory Presence of Dipeptide GlyGly at Processing Site. APPL BIOCHEM MICRO+ 2019. [DOI: 10.1134/s0003683819090060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Salmonella enterica Effectors SifA, SpvB, SseF, SseJ, and SteA Contribute to Type III Secretion System 1-Independent Inflammation in a Streptomycin-Pretreated Mouse Model of Colitis. Infect Immun 2019; 87:IAI.00872-18. [PMID: 31235639 DOI: 10.1128/iai.00872-18] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 06/11/2019] [Indexed: 01/13/2023] Open
Abstract
Salmonella enterica serovar Typhimurium (S. Typhimurium) induces inflammatory changes in the ceca of streptomycin-pretreated mice. In this mouse model of colitis, the type III secretion system 1 (T3SS-1) has been shown to induce rapid inflammatory change in the cecum at early points, 10 to 24 h after infection. Five proteins, SipA, SopA, SopB, SopD, and SopE2, have been identified as effectors involved in eliciting intestinal inflammation within this time range. In contrast, a T3SS-1-deficient strain was shown to exhibit inflammatory changes in the cecum at 72 to 120 h postinfection. However, the effectors eliciting T3SS-1-independent inflammation remain to be clarified. In this study, we focused on two T3SS-2 phenotypes, macrophage proliferation and cytotoxicity, to identify the T3SS-2 effectors involved in T3SS-1-independent inflammation. We identified a mutant strain that could not induce cytotoxicity in a macrophage-like cell line and that reduced intestinal inflammation in streptomycin-pretreated mice. We also identified five T3SS-2 effectors, SifA, SpvB, SseF, SseJ, and SteA, associated with T3SS-1-independent macrophage cytotoxicity. We then constructed a strain lacking T3SS-1 and all the five T3SS-2 effectors, termed T1S5. The S. Typhimurium T1S5 strain significantly reduced cytotoxicity in macrophages in the same manner as a mutant invA spiB strain (T1T2). Finally, the T1S5 strain elicited no inflammatory changes in the ceca of streptomycin-pretreated mice. We conclude that these five T3SS-2 effectors contribute to T3SS-1-independent inflammation.
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Geng S, Wang Y, Xue Y, Wang H, Cai Y, Zhang J, Barrow P, Pan Z, Jiao X. The SseL protein inhibits the intracellular NF-κB pathway to enhance the virulence of Salmonella Pullorum in a chicken model. Microb Pathog 2019; 129:1-6. [PMID: 30703474 DOI: 10.1016/j.micpath.2019.01.035] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 01/22/2019] [Accepted: 01/22/2019] [Indexed: 10/27/2022]
Abstract
To persist in the host, Salmonella is known to facultatively parasitize cells to escape the immune response. Intracellular Salmonella enterica can replicate using effector proteins translocated across the Salmonella-containing vacuolar membrane via a type III secretion system (T3SS) encoded by Salmonella pathogenicity island-2 (SPI-2). One of these factors, Salmonella secreted factor L (SseL), is a deubiquitinase that contributes to the virulence of Salmonella Typhimurium in mice by inhibiting the cellular NF-κB inflammatory pathway. However, the nature of its effect on the NF-κB pathway is controversial, and little research has been performed in other animal models. In this study, the SseL of Salmonella Pullorum was studied, and chickens were used as an infection model. An sseL gene deletion strain, a complementation strain and a eukaryotic expression plasmid were used to clarify the means by which SseL regulates Salmonella virulence and the cellular inflammatory response. SseL significantly enhanced the virulence of Salmonella Pullorum in chickens and suppressed activation of the cellular NF-κB pathway, thus inhibiting cellular inflammatory cytokine expression.
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Affiliation(s)
- Shizhong Geng
- Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China.
| | - Yaonan Wang
- Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China
| | - Ying Xue
- Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China
| | - Huqiang Wang
- Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China
| | - Yuan Cai
- Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China
| | - Jian Zhang
- Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China
| | - Paul Barrow
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Sutton Bonington, Loughborough, Leicestershire, LE12 5RD, UK
| | - Zhiming Pan
- Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China
| | - Xinan Jiao
- Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China.
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Herhaus L, Dikic I. Regulation of Salmonella-host cell interactions via the ubiquitin system. Int J Med Microbiol 2017; 308:176-184. [PMID: 29126744 DOI: 10.1016/j.ijmm.2017.11.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 11/01/2017] [Accepted: 11/05/2017] [Indexed: 01/29/2023] Open
Abstract
Salmonella infections cause acute intestinal inflammatory responses through the action of bacterial effector proteins secreted into the host cytosol. These proteins promote Salmonella survival, amongst others, by deregulating the host innate immune system and interfering with host cell ubiquitylation signaling. This review describes the recent findings of dynamic changes of the host ubiquitinome during pathogen infection, how bacterial effector proteins modulate the host ubiquitin system and how the host innate immune system counteracts Salmonella invasion by using these pathogens as signaling platforms to initiate immune responses.
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Affiliation(s)
- Lina Herhaus
- Institute of Biochemistry II, Goethe University Frankfurt - Medical Faculty, University Hospital, 60590 Frankfurt am Main, Germany
| | - Ivan Dikic
- Institute of Biochemistry II, Goethe University Frankfurt - Medical Faculty, University Hospital, 60590 Frankfurt am Main, Germany; Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Riedberg Campus, 60438 Frankfurt am Main, Germany.
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Identification of Novel Host Interactors of Effectors Secreted by Salmonella and Citrobacter. mSystems 2016; 1:mSystems00032-15. [PMID: 27822540 PMCID: PMC5069955 DOI: 10.1128/msystems.00032-15] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 06/16/2016] [Indexed: 11/24/2022] Open
Abstract
During infection, pathogenic bacteria face an adverse environment of factors driven by both cellular and humoral defense mechanisms. To help evade the immune response and ultimately proliferate inside the host, many bacteria evolved specialized secretion systems to deliver effector proteins directly into host cells. Translocated effector proteins function to subvert host defense mechanisms. Numerous pathogenic bacteria use a specialized secretion system called type III secretion to deliver effectors into the host cell cytosol. Here, we identified 75 new host targets of Salmonella and Citrobacter effectors, which will help elucidate their mechanisms of action. Many pathogenic bacteria of the family Enterobacteriaceae use type III secretion systems to inject virulence proteins, termed “effectors,” into the host cell cytosol. Although host-cellular activities of several effectors have been demonstrated, the function and host-targeted pathways of most of the effectors identified to date are largely undetermined. To gain insight into host proteins targeted by bacterial effectors, we performed coaffinity purification of host proteins from cell lysates using recombinant effectors from the Enterobacteriaceae intracellular pathogens Salmonella enterica serovar Typhimurium and Citrobacter rodentium. We identified 54 high-confidence host interactors for the Salmonella effectors GogA, GtgA, GtgE, SpvC, SrfH, SseL, SspH1, and SssB collectively and 21 interactors for the Citrobacter effectors EspT, NleA, NleG1, and NleK. We biochemically validated the interaction between the SrfH Salmonella protein and the extracellular signal-regulated kinase 2 (ERK2) host protein kinase, which revealed a role for this effector in regulating phosphorylation levels of this enzyme, which plays a central role in signal transduction. IMPORTANCE During infection, pathogenic bacteria face an adverse environment of factors driven by both cellular and humoral defense mechanisms. To help evade the immune response and ultimately proliferate inside the host, many bacteria evolved specialized secretion systems to deliver effector proteins directly into host cells. Translocated effector proteins function to subvert host defense mechanisms. Numerous pathogenic bacteria use a specialized secretion system called type III secretion to deliver effectors into the host cell cytosol. Here, we identified 75 new host targets of Salmonella and Citrobacter effectors, which will help elucidate their mechanisms of action.
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Fiskin E, Bionda T, Dikic I, Behrends C. Global Analysis of Host and Bacterial Ubiquitinome in Response to Salmonella Typhimurium Infection. Mol Cell 2016; 62:967-981. [PMID: 27211868 DOI: 10.1016/j.molcel.2016.04.015] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 03/08/2016] [Accepted: 04/12/2016] [Indexed: 12/14/2022]
Abstract
Ubiquitination serves as a critical signal in the host immune response to infection. Many pathogens have evolved strategies to exploit the ubiquitin (Ub) system to promote their own survival through a complex interplay between host defense machinery and bacterial virulence factors. Here we report dynamic changes in the global ubiquitinome of host epithelial cells and invading pathogen in response to Salmonella Typhimurium infection. The most significant alterations in the host ubiquitinome concern components of the actin cytoskeleton, NF-κB and autophagy pathways, and the Ub and RHO GTPase systems. Specifically, infection-induced ubiquitination promotes CDC42 activity and linear ubiquitin chain formation, both being required for NF-κB activation. Conversely, the bacterial ubiquitinome exhibited extensive ubiquitination of various effectors and several outer membrane proteins. Moreover, we reveal that bacterial Ub-modifying enzymes modulate a unique subset of host targets, affecting different stages of Salmonella infection.
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Affiliation(s)
- Evgenij Fiskin
- Institute of Biochemistry II, Goethe University School of Medicine, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
| | - Tihana Bionda
- Institute of Biochemistry II, Goethe University School of Medicine, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
| | - Ivan Dikic
- Institute of Biochemistry II, Goethe University School of Medicine, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany; Buchmann Institute for Molecular Life Sciences, Goethe University, Max-von-Laue-Strasse 15, 60438 Frankfurt am Main, Germany; Department of Immunology and Medical Genetics, School of Medicine, University of Split, Soltanska 2, 21 000 Split, Croatia.
| | - Christian Behrends
- Institute of Biochemistry II, Goethe University School of Medicine, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany.
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