1
|
Galaud JP, Genin S, Aldon D. Pathogen effectors hijack calcium signaling to promote virulence. TRENDS IN PLANT SCIENCE 2024:S1360-1385(24)00280-2. [PMID: 39523142 DOI: 10.1016/j.tplants.2024.10.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Revised: 10/18/2024] [Accepted: 10/18/2024] [Indexed: 11/16/2024]
Abstract
Calcium signaling is a cornerstone of plant defense responses. In this opinion article we explore how pathogens exploit this pathway by targeting calcium sensors such as calmodulin (CaM) and calmodulin-like proteins (CMLs) with their secreted effectors. We illustrate different mechanisms by which effectors manipulate calcium homeostasis, cytoskeletal dynamics, metabolism, hormone biosynthesis, gene regulation, and chloroplast function to suppress plant immunity and enhance virulence. Targeting calcium signaling to thwart or weaken host defenses appears to be a common strategy among pathogens infecting animal cells, and we present here selected examples of this convergence. Understanding these strategies provides valuable insights into the interactions between plants and pathogens, and should pave the way for the development of new disease control strategies.
Collapse
Affiliation(s)
- Jean-Philippe Galaud
- Laboratoire de Recherche en Sciences Végétales, UMR 5546, Université de Toulouse, CNRS-UPS-INP, 31320, Auzeville-Tolosane, France.
| | - Stéphane Genin
- LIPME, Université de Toulouse, INRAE, CNRS, Castanet-Tolosan, France
| | - Didier Aldon
- Laboratoire de Recherche en Sciences Végétales, UMR 5546, Université de Toulouse, CNRS-UPS-INP, 31320, Auzeville-Tolosane, France
| |
Collapse
|
2
|
Wanford JJ, Odendall C. Ca 2+-calmodulin signalling at the host-pathogen interface. Curr Opin Microbiol 2023; 72:102267. [PMID: 36716574 DOI: 10.1016/j.mib.2023.102267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 12/19/2022] [Accepted: 01/04/2023] [Indexed: 01/29/2023]
Abstract
Multiple eukaryotic cell processes are modulated by calcium ions (Ca2+). As such, Ca2+ is emerging as a crucial regulator of innate immunity in multicellular organisms. In particular, recent studies have identified roles of Ca2+ signalling at the host-bacteria interface. Following microbial exposure, Ca2+ signals mobilised from the extracellular milieu or intracellular stores are transduced into cell physiological responses. However, during infection with host-adapted pathogens, Ca2+ signals are often atypical, due to the activities of virulence factors, with varied consequences for both the pathogen and the host cell. In this review, we describe the Ca2+-dependent host factors regulating antibacterial immunity, in addition to bacterial effectors that promote, inhibit, or co-opt Ca2+-calmodulin signalling to promote infection.
Collapse
Affiliation(s)
- Joseph J Wanford
- School of Immunology and Microbial Sciences, Kings College London, London, UK
| | - Charlotte Odendall
- School of Immunology and Microbial Sciences, Kings College London, London, UK.
| |
Collapse
|
3
|
Tran Van Nhieu G, Latour-Lambert P, Enninga J. Modification of phosphoinositides by the Shigella effector IpgD during host cell infection. Front Cell Infect Microbiol 2022; 12:1012533. [PMID: 36389142 PMCID: PMC9647168 DOI: 10.3389/fcimb.2022.1012533] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 09/27/2022] [Indexed: 09/15/2023] Open
Abstract
Shigella, the causative agent of bacillary dysentery, subvert cytoskeletal and trafficking processes to invade and replicate in epithelial cells using an arsenal of bacterial effectors translocated through a type III secretion system. Here, we review the various roles of the type III effector IpgD, initially characterized as phosphatidylinositol 4,5 bisphosphate (PI4,5P2) 4-phosphatase. By decreasing PI4,5P2 levels, IpgD triggers the disassembly of cortical actin filaments required for bacterial invasion and cell migration. PI5P produced by IpgD further stimulates signaling pathways regulating cell survival, macropinosome formation, endosomal trafficking and dampening of immune responses. Recently, IpgD was also found to exhibit phosphotransferase activity leading to PI3,4P2 synthesis adding a new flavor to this multipotent bacterial enzyme. The substrate of IpgD, PI4,5P2 is also the main substrate hydrolyzed by endogenous phospholipases C to produce inositoltriphosphate (InsP3), a major Ca2+ second messenger. Hence, beyond the repertoire of effects associated with the direct diversion of phoshoinositides, IpgD indirectly down-regulates InsP3-mediated Ca2+ release by limiting InsP3 production. Furthermore, IpgD controls the intracellular lifestyle of Shigella promoting Rab8/11 -dependent recruitment of the exocyst at macropinosomes to remove damaged vacuolar membrane remnants and promote bacterial cytosolic escape. IpgD thus emerges as a key bacterial effector for the remodeling of host cell membranes.
Collapse
Affiliation(s)
- Guy Tran Van Nhieu
- Institute for Integrative Biology of the Cell – Centre National de la Recherche Scientifique (CNRS) UMR9198 - Institut National de la Santé et de la Recherche Médicale (Inserm) U1280, Team Calcium Signaling and Microbial Infections, Gif-sur-Yvette, France
| | - Patricia Latour-Lambert
- Institut Pasteur, Unité Dynamique des interactions hôtes-pathogènes and Centre National de la Recherche Scientifique (CNRS) UMR3691, Université de Paris Cité, Paris, France
| | - Jost Enninga
- Institut Pasteur, Unité Dynamique des interactions hôtes-pathogènes and Centre National de la Recherche Scientifique (CNRS) UMR3691, Université de Paris Cité, Paris, France
| |
Collapse
|
4
|
Reprogramming of Cell Death Pathways by Bacterial Effectors as a Widespread Virulence Strategy. Infect Immun 2022; 90:e0061421. [PMID: 35467397 DOI: 10.1128/iai.00614-21] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The modulation of programmed cell death (PCD) processes during bacterial infections is an evolving arms race between pathogens and their hosts. The initiation of apoptosis, necroptosis, and pyroptosis pathways are essential to immunity against many intracellular and extracellular bacteria. These cellular self-destructive mechanisms are used by the infected host to restrict and eliminate bacterial pathogens. Without a tight regulatory control, host cell death can become a double-edged sword. Inflammatory PCDs contribute to an effective immune response against pathogens, but unregulated inflammation aggravates the damage caused by bacterial infections. Thus, fine-tuning of these pathways is required to resolve infection while preserving the host immune homeostasis. In turn, bacterial pathogens have evolved secreted virulence factors or effector proteins that manipulate PCD pathways to promote infection. In this review, we discuss the importance of controlled cell death in immunity to bacterial infection. We also detail the mechanisms employed by type 3 secreted bacterial effectors to bypass these pathways and their importance in bacterial pathogenesis.
Collapse
|
5
|
Palit P, Chowdhury FT, Baruah N, Sarkar B, Mou SN, Kamal M, Siddiqua TJ, Noor Z, Ahmed T. A Comprehensive Computational Investigation into the Conserved Virulent Proteins of Shigella species Unveils Potential Small-Interfering RNA Candidates as a New Therapeutic Strategy against Shigellosis. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27061936. [PMID: 35335300 PMCID: PMC8950558 DOI: 10.3390/molecules27061936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 12/19/2021] [Accepted: 12/27/2021] [Indexed: 11/16/2022]
Abstract
Shigella species account for the second-leading cause of deaths due to diarrheal diseases among children of less than 5 years of age. The emergence of multi-drug-resistant Shigella isolates and the lack of availability of Shigella vaccines have led to the pertinence in the efforts made for the development of new therapeutic strategies against shigellosis. Consequently, designing small-interfering RNA (siRNA) candidates against such infectious agents represents a novel approach to propose new therapeutic candidates to curb the rampant rise of anti-microbial resistance in such pathogens. In this study, we analyzed 264 conserved sequences from 15 different conserved virulence genes of Shigella sp., through extensive rational validation using a plethora of first-generation and second-generation computational algorithms for siRNA designing. Fifty-eight siRNA candidates were obtained by using the first-generation algorithms, out of which only 38 siRNA candidates complied with the second-generation rules of siRNA designing. Further computational validation showed that 16 siRNA candidates were found to have a substantial functional efficiency, out of which 11 siRNA candidates were found to be non-immunogenic. Finally, three siRNA candidates exhibited a sterically feasible three-dimensional structure as exhibited by parameters of nucleic acid geometry such as: the probability of wrong sugar puckers, bad backbone confirmations, bad bonds, and bad angles being within the accepted threshold for stable tertiary structure. Although the findings of our study require further wet-lab validation and optimization for therapeutic use in the treatment of shigellosis, the computationally validated siRNA candidates are expected to suppress the expression of the virulence genes, namely: IpgD (siRNA 9) and OspB (siRNA 15 and siRNA 17) and thus act as a prospective tool in the RNA interference (RNAi) pathway. However, the findings of our study require further wet-lab validation and optimization for regular therapeutic use for treatment of shigellosis.
Collapse
Affiliation(s)
- Parag Palit
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka 1212, Bangladesh; (P.P.); (M.K.); (T.J.S.); (T.A.)
| | - Farhana Tasnim Chowdhury
- Department of Biochemistry and Molecular Biology, University of Dhaka, Dhaka 1000, Bangladesh; (F.T.C.); (B.S.); (S.N.M.)
| | - Namrata Baruah
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, Uttar Pradesh, India;
| | - Bonoshree Sarkar
- Department of Biochemistry and Molecular Biology, University of Dhaka, Dhaka 1000, Bangladesh; (F.T.C.); (B.S.); (S.N.M.)
| | - Sadia Noor Mou
- Department of Biochemistry and Molecular Biology, University of Dhaka, Dhaka 1000, Bangladesh; (F.T.C.); (B.S.); (S.N.M.)
| | - Mehnaz Kamal
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka 1212, Bangladesh; (P.P.); (M.K.); (T.J.S.); (T.A.)
| | - Towfida Jahan Siddiqua
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka 1212, Bangladesh; (P.P.); (M.K.); (T.J.S.); (T.A.)
| | - Zannatun Noor
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka 1212, Bangladesh; (P.P.); (M.K.); (T.J.S.); (T.A.)
- Correspondence:
| | - Tahmeed Ahmed
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka 1212, Bangladesh; (P.P.); (M.K.); (T.J.S.); (T.A.)
| |
Collapse
|
6
|
Prista von Bonhorst F, Gall D, Dupont G. Impact of β-Amyloids Induced Disruption of Ca2+ Homeostasis in a Simple Model of Neuronal Activity. Cells 2022; 11:cells11040615. [PMID: 35203266 PMCID: PMC8869902 DOI: 10.3390/cells11040615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 01/31/2022] [Accepted: 02/01/2022] [Indexed: 01/25/2023] Open
Abstract
Alzheimer’s disease is characterized by a marked dysregulation of intracellular Ca2+ homeostasis. In particular, toxic β-amyloids (Aβ) perturb the activities of numerous Ca2+ transporters or channels. Because of the tight coupling between Ca2+ dynamics and the membrane electrical activity, such perturbations are also expected to affect neuronal excitability. We used mathematical modeling to systematically investigate the effects of changing the activities of the various targets of Aβ peptides reported in the literature on calcium dynamics and neuronal excitability. We found that the evolution of Ca2+ concentration just below the plasma membrane is regulated by the exchanges with the extracellular medium, and is practically independent from the Ca2+ exchanges with the endoplasmic reticulum. Thus, disruptions of Ca2+ homeostasis interfering with signaling do not affect the electrical properties of the neurons at the single cell level. In contrast, the model predicts that by affecting the activities of L-type Ca2+ channels or Ca2+-activated K+ channels, Aβ peptides promote neuronal hyperexcitability. On the contrary, they induce hypo-excitability when acting on the plasma membrane Ca2+ ATPases. Finally, the presence of pores of amyloids in the plasma membrane can induce hypo- or hyperexcitability, depending on the conditions. These modeling conclusions should help with analyzing experimental observations in which Aβ peptides interfere at several levels with Ca2+ signaling and neuronal activity.
Collapse
Affiliation(s)
- Francisco Prista von Bonhorst
- Unit of Theoretical Chronobiology, Faculté des Sciences (CP231), Université Libre de Bruxelles (ULB), 1050 Brussels, Belgium;
| | - David Gall
- Research Laboratory in Human Reproduction, Faculté de Médecine (CP636), Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium;
| | - Geneviève Dupont
- Unit of Theoretical Chronobiology, Faculté des Sciences (CP231), Université Libre de Bruxelles (ULB), 1050 Brussels, Belgium;
- Correspondence:
| |
Collapse
|
7
|
Marchi S, Morroni G, Pinton P, Galluzzi L. Control of host mitochondria by bacterial pathogens. Trends Microbiol 2021; 30:452-465. [PMID: 34656395 DOI: 10.1016/j.tim.2021.09.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 09/22/2021] [Accepted: 09/27/2021] [Indexed: 12/14/2022]
Abstract
Mitochondria control various processes that are integral to cellular and organismal homeostasis, including Ca2+ fluxes, bioenergetic metabolism, and cell death. Perhaps not surprisingly, multiple pathogenic bacteria have evolved strategies to subvert mitochondrial functions in support of their survival and dissemination. Here, we discuss nonimmunological pathogenic mechanisms that converge on the ability of bacteria to control the mitochondrial compartment of host cells.
Collapse
Affiliation(s)
- Saverio Marchi
- Department of Clinical and Molecular Sciences, Marche Polytechnic University, Ancona, Italy.
| | - Gianluca Morroni
- Department of Biomedical Sciences & Public Health, Marche Polytechnic University, Ancona, Italy
| | - Paolo Pinton
- Department of Medical Sciences, Section of Experimental Medicine, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Lorenzo Galluzzi
- Department of Radiation Oncology, Weill Cornell Medical College, New York, NY, USA; Sandra and Edward Meyer Cancer Center, New York, NY, USA; Caryl and Israel Englander Institute for Precision Medicine, New York, NY, USA; Department of Dermatology, Yale School of Medicine, New Haven, CT, USA; Université de Paris, Paris, France.
| |
Collapse
|
8
|
Hajra D, Nair AV, Chakravortty D. An elegant nano-injection machinery for sabotaging the host: Role of Type III secretion system in virulence of different human and animal pathogenic bacteria. Phys Life Rev 2021; 38:25-54. [PMID: 34090822 DOI: 10.1016/j.plrev.2021.05.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Accepted: 05/23/2021] [Indexed: 01/22/2023]
Abstract
Various Gram-negative bacteria possess a specialized membrane-bound protein secretion system known as the Type III secretion system (T3SS), which transports the bacterial effector proteins into the host cytosol thereby helping in bacterial pathogenesis. The T3SS has a special needle-like translocon that can sense the contact with the host cell membrane and translocate effectors. The export apparatus of T3SS recognizes these effector proteins bound to chaperones and translocates them into the host cell. Once in the host cell cytoplasm, these effector proteins result in modulation of the host system and promote bacterial localization and infection. Using molecular biology, bioinformatics, genetic techniques, electron microscopic studies, and mathematical modeling, the structure and function of the T3SS and the corresponding effector proteins in various bacteria have been studied. The strategies used by different human pathogenic bacteria to modulate the host system and thereby enhance their virulence mechanism using T3SS have also been well studied. Here we review the history, evolution, and general structure of the T3SS, highlighting the details of its comparison with the flagellar export machinery. Also, this article provides mechanistic details about the common role of T3SS in subversion and manipulation of host cellular processes. Additionally, this review describes specific T3SS apparatus and the role of their specific effectors in bacterial pathogenesis by considering several human and animal pathogenic bacteria.
Collapse
Affiliation(s)
- Dipasree Hajra
- Department of Microbiology & Cell Biology, Indian Institute of Science, India
| | - Abhilash Vijay Nair
- Department of Microbiology & Cell Biology, Indian Institute of Science, India
| | | |
Collapse
|
9
|
Abstract
Despite being regarded as an extracellular bacterium, the pathogen Staphylococcus aureus can invade and survive within human cells. The intracellular niche is considered a hideout from the host immune system and antibiotic treatment and allows bacterial proliferation. The opportunistic human pathogen Staphylococcus aureus causes serious infectious diseases that range from superficial skin and soft tissue infections to necrotizing pneumonia and sepsis. While classically regarded as an extracellular pathogen, S. aureus is able to invade and survive within human cells. Host cell exit is associated with cell death, tissue destruction, and the spread of infection. The exact molecular mechanism employed by S. aureus to escape the host cell is still unclear. In this study, we performed a genome-wide small hairpin RNA (shRNA) screen and identified the calcium signaling pathway as being involved in intracellular infection. S. aureus induced a massive cytosolic Ca2+ increase in epithelial host cells after invasion and intracellular replication of the pathogen. This was paralleled by a decrease in endoplasmic reticulum Ca2+ concentration. Additionally, calcium ions from the extracellular space contributed to the cytosolic Ca2+ increase. As a consequence, we observed that the cytoplasmic Ca2+ rise led to an increase in mitochondrial Ca2+ concentration, the activation of calpains and caspases, and eventually to cell lysis of S. aureus-infected cells. Our study therefore suggests that intracellular S. aureus disturbs the host cell Ca2+ homeostasis and induces cytoplasmic Ca2+ overload, which results in both apoptotic and necrotic cell death in parallel or succession.
Collapse
|
10
|
Shigella IpaA Binding to Talin Stimulates Filopodial Capture and Cell Adhesion. Cell Rep 2020; 26:921-932.e6. [PMID: 30673614 DOI: 10.1016/j.celrep.2018.12.091] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 11/07/2018] [Accepted: 12/20/2018] [Indexed: 01/22/2023] Open
Abstract
The Shigella type III effector IpaA contains three binding sites for the focal adhesion protein vinculin (VBSs), which are involved in bacterial invasion of host cells. Here, we report that IpaA VBS3 unexpectedly binds to talin. The 2.5 Å resolution crystal structure of IpaA VBS3 in complex with the talin H1-H4 helices shows a tightly folded α-helical bundle, which is in contrast to the bundle unraveling upon vinculin interaction. High-affinity binding to talin H1-H4 requires a core of hydrophobic residues and electrostatic interactions conserved in talin VBS H46. Remarkably, IpaA VBS3 localizes to filopodial distal adhesions enriched in talin, but not vinculin. In addition, IpaA VBS3 binding to talin was required for filopodial adhesions and efficient capture of Shigella. These results point to the functional diversity of VBSs and support a specific role for talin binding by a subset of VBSs in the formation of filopodial adhesions.
Collapse
|
11
|
Powell J, Falcke M, Skupin A, Bellamy TC, Kypraios T, Thul R. A Statistical View on Calcium Oscillations. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1131:799-826. [PMID: 31646535 DOI: 10.1007/978-3-030-12457-1_32] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Transient rises and falls of the intracellular calcium concentration have been observed in numerous cell types and under a plethora of conditions. There is now a growing body of evidence that these whole-cell calcium oscillations are stochastic, which poses a significant challenge for modelling. In this review, we take a closer look at recently developed statistical approaches to calcium oscillations. These models describe the timing of whole-cell calcium spikes, yet their parametrisations reflect subcellular processes. We show how non-stationary calcium spike sequences, which e.g. occur during slow depletion of intracellular calcium stores or in the presence of time-dependent stimulation, can be analysed with the help of so-called intensity functions. By utilising Bayesian concepts, we demonstrate how values of key parameters of the statistical model can be inferred from single cell calcium spike sequences and illustrate what information whole-cell statistical models can provide about the subcellular mechanistic processes that drive calcium oscillations. In particular, we find that the interspike interval distribution of HEK293 cells under constant stimulation is captured by a Gamma distribution.
Collapse
Affiliation(s)
- Jake Powell
- Centre for Mathematical Medicine and Biology, School of Mathematical Sciences, University of Nottingham, Nottingham, UK
| | - Martin Falcke
- Max Delbrück Centre for Molecular Medicine, Berlin, Germany.,Department of Physics, Humboldt University, Berlin, Germany
| | - Alexander Skupin
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Belval, Luxembourg.,National Biomedical Computation Resource, University California San Diego, La Jolla, CA, USA
| | - Tomas C Bellamy
- School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Theodore Kypraios
- Centre for Mathematical Medicine and Biology, School of Mathematical Sciences, University of Nottingham, Nottingham, UK
| | - Rüdiger Thul
- Centre for Mathematical Medicine and Biology, School of Mathematical Sciences, University of Nottingham, Nottingham, UK.
| |
Collapse
|
12
|
Schnupf P, Sansonetti PJ. Shigella Pathogenesis: New Insights through Advanced Methodologies. Microbiol Spectr 2019; 7:10.1128/microbiolspec.bai-0023-2019. [PMID: 30953429 PMCID: PMC11588159 DOI: 10.1128/microbiolspec.bai-0023-2019] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Indexed: 02/07/2023] Open
Abstract
Shigella is a genus of Gram-negative enteropathogens that have long been, and continue to be, an important public health concern worldwide. Over the past several decades, Shigella spp. have also served as model pathogens in the study of bacterial pathogenesis, and Shigella flexneri has become one of the best-studied pathogens on a molecular, cellular, and tissue level. In the arms race between Shigella and the host immune system, Shigella has developed highly sophisticated mechanisms to subvert host cell processes in order to promote infection, escape immune detection, and prevent bacterial clearance. Here, we give an overview of Shigella pathogenesis while highlighting innovative techniques and methods whose application has significantly advanced our understanding of Shigella pathogenesis in recent years.
Collapse
Affiliation(s)
- Pamela Schnupf
- Institut Imagine, Laboratory of Intestinal Immunity, INSERM UMR1163; Institut Necker Enfants Malades, Laboratory of Host-Microbiota Interaction, INSERM U1151; and Université Paris Descartes-Sorbonne, 75006 Paris, France
| | - Philippe J Sansonetti
- Institut Pasteur, Unité de Pathogénie Microbienne Moléculaire, INSERM U1202, and College de France, Paris, France
| |
Collapse
|
13
|
Wacquier B, Voorsluijs V, Combettes L, Dupont G. Coding and decoding of oscillatory Ca 2+ signals. Semin Cell Dev Biol 2019; 94:11-19. [PMID: 30659886 DOI: 10.1016/j.semcdb.2019.01.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 01/11/2019] [Accepted: 01/14/2019] [Indexed: 01/08/2023]
Abstract
About 30 years after their first observation, Ca2+ oscillations are now recognised as a universal mechanism of signal transduction. These oscillations are driven by periodic cycles of release and uptake of Ca2+ between the cytoplasm and the endoplasmic reticulum. Their frequency often increases with the level of stimulation, which can be decoded by some molecules. However, it is becoming increasingly evident that the widespread core oscillatory mechanism is modulated in many ways, depending on the cell type and on the physiological conditions. Interplay with inositol 1,4,5-trisphosphate metabolism and with other Ca2+ stores as the extracellular medium or mitochondria can much affect the properties of these oscillations. In many cases, these finely tuned characteristics of Ca2+ oscillations impact the physiological response that is triggered by the signal. Moreover, oscillations are intrinsically irregular. This randomness can also be exploited by the cell. In this review, we discuss evidences of these additional manifestations of the versatility of Ca2+ signalling.
Collapse
Affiliation(s)
- Benjamin Wacquier
- Unit of Theoretical Chronobiology, Faculté des Sciences, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Valérie Voorsluijs
- Nonlinear Physical Chemistry Unit & Center for Nonlinear Phenomena and Complex Systems (CENOLI), Université Libre de Bruxelles (ULB), Brussels, Belgium
| | | | - Geneviève Dupont
- Unit of Theoretical Chronobiology, Faculté des Sciences, Université Libre de Bruxelles (ULB), Brussels, Belgium.
| |
Collapse
|
14
|
Ca2+ signals triggered by bacterial pathogens and microdomains. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1865:1838-1845. [DOI: 10.1016/j.bbamcr.2018.08.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 08/08/2018] [Accepted: 08/10/2018] [Indexed: 12/15/2022]
|
15
|
Abstract
Shigella is an intracellular pathogen that invades the human host cell cytosol and exploits intracellular nutrients for growth, enabling the bacterium to create its own metabolic niche. For Shigella to effectively invade and replicate within the host cytoplasm, it must sense and adapt to changing environmental conditions; however, the mechanisms and signals sensed by S. flexneri are largely unknown. We have found that the secreted Shigella metabolism by-product formate regulates Shigella intracellular virulence gene expression and its ability to spread among epithelial cells. We propose that Shigella senses formate accumulation in the host cytosol as a way to determine intracellular Shigella density and regulate secreted virulence factors accordingly, enabling spatiotemporal regulation of effectors important for dampening the host immune response. The intracellular human pathogen Shigella flexneri invades the colon epithelium, replicates to high cell density within the host cell, and then spreads to adjacent epithelial cells. When S. flexneri gains access to the host cytosol, the bacteria metabolize host cytosolic carbon using glycolysis and mixed acid fermentation, producing formate as a by-product. We show that S. flexneri infection results in the accumulation of formate within the host cell. Loss of pyruvate formate lyase (PFL; ΔpflB), which converts pyruvate to acetyl coenzyme A (CoA) and formate, eliminates S. flexneri formate production and reduces the ability of S. flexneri to form plaques in epithelial cell monolayers. This defect in PFL does not decrease the intracellular growth rate of S. flexneri; rather, it affects cell-to-cell spread. The S. flexneri ΔpflB mutant plaque defect is complemented by supplying exogenous formate; conversely, deletion of the S. flexneri formate dehydrogenase gene fdnG increases host cell formate accumulation and S. flexneri plaque size. Furthermore, exogenous formate increases plaque size of the wild-type (WT) S. flexneri strain and promotes S. flexneri cell-to-cell spread. We also demonstrate that formate increases the expression of S. flexneri virulence genes icsA and ipaJ. Intracellular S. flexneriicsA and ipaJ expression is dependent on the presence of formate, and ipaJ expression correlates with S. flexneri intracellular density during infection. Finally, consistent with elevated ipaJ, we show that formate alters S. flexneri-infected host interferon- and tumor necrosis factor (TNF)-stimulated gene expression. We propose that Shigella-derived formate is an intracellular signal that modulates virulence in response to bacterial metabolism.
Collapse
|
16
|
Smail Y, Sun C, Combettes L, Tran Van Nhieu G. Imaging Ca2+ Responses During Shigella Infection of Epithelial Cells. J Vis Exp 2018. [PMID: 29889185 DOI: 10.3791/57728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Ca2+ is a ubiquitous ion involved in all known cellular processes. While global Ca2+ responses may affect cell fate, local variations in free Ca2+ cytosolic concentrations, linked to release from internal stores or an influx through plasma membrane channels, regulate cortical cell processes. Pathogens that adhere to or invade host cells trigger a reorganization of the actin cytoskeleton underlying the host plasma membrane, which likely affects both global and local Ca2+ signaling. Because these events may occur at low frequencies in a pseudo-stochastic manner over extended kinetics, the analysis of Ca2+ signals induced by pathogens raises major technical challenges that need to be addressed. Here, we report protocols for the detection of global and local Ca2+ signals upon a Shigella infection of epithelial cells. In these protocols, artefacts linked to a prolonged exposure and photodamage associated with the excitation of Ca2+ fluorescent probes are troubleshot by stringently controlling the acquisition parameters over defined time periods during a Shigella invasion. Procedures are implemented to rigorously analyze the amplitude and frequency of global cytosolic Ca2+ signals during extended infection kinetics using the chemical probe Fluo-4.
Collapse
Affiliation(s)
- Yasmine Smail
- Equipe Communication Intercellulaire et Infections Microbiennes, Centre de Recherche Interdisciplinaire en Biologie (CIRB), Collège de France; Institut National de la Santé et de la Recherche Médicale (Inserm), U1050; Centre Nationale de la Recherche Scientifique (CNRS), UMR7241; MEMOLIFE Laboratory of Excellence and Paris Sciences et Lettres
| | - Chunhui Sun
- Equipe Communication Intercellulaire et Infections Microbiennes, Centre de Recherche Interdisciplinaire en Biologie (CIRB), Collège de France; Institut National de la Santé et de la Recherche Médicale (Inserm), U1050; Centre Nationale de la Recherche Scientifique (CNRS), UMR7241; MEMOLIFE Laboratory of Excellence and Paris Sciences et Lettres
| | | | - Guy Tran Van Nhieu
- Equipe Communication Intercellulaire et Infections Microbiennes, Centre de Recherche Interdisciplinaire en Biologie (CIRB), Collège de France; Institut National de la Santé et de la Recherche Médicale (Inserm), U1050; Centre Nationale de la Recherche Scientifique (CNRS), UMR7241; MEMOLIFE Laboratory of Excellence and Paris Sciences et Lettres;
| |
Collapse
|
17
|
Pinaud L, Sansonetti PJ, Phalipon A. Host Cell Targeting by Enteropathogenic Bacteria T3SS Effectors. Trends Microbiol 2018; 26:266-283. [DOI: 10.1016/j.tim.2018.01.010] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 01/29/2018] [Accepted: 01/29/2018] [Indexed: 12/23/2022]
|
18
|
Sun CH, Wacquier B, Aguilar DI, Carayol N, Denis K, Boucherie S, Valencia-Gallardo C, Simsek C, Erneux C, Lehman A, Enninga J, Arbibe L, Sansonetti P, Dupont G, Combettes L, Tran Van Nhieu G. The Shigella type III effector IpgD recodes Ca 2+ signals during invasion of epithelial cells. EMBO J 2017; 36:2567-2580. [PMID: 28701483 PMCID: PMC5579377 DOI: 10.15252/embj.201696272] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 06/03/2017] [Accepted: 06/13/2017] [Indexed: 01/29/2023] Open
Abstract
The role of second messengers in the diversion of cellular processes by pathogens remains poorly studied despite their importance. Among these, Ca2+ virtually regulates all known cell processes, including cytoskeletal reorganization, inflammation, or cell death pathways. Under physiological conditions, cytosolic Ca2+ increases are transient and oscillatory, defining the so-called Ca2+ code that links cell responses to specific Ca2+ oscillatory patterns. During cell invasion, Shigella induces atypical local and global Ca2+ signals. Here, we show that by hydrolyzing phosphatidylinositol-(4,5)bisphosphate, the Shigella type III effector IpgD dampens inositol-(1,4,5)trisphosphate (InsP3) levels. By modifying InsP3 dynamics and diffusion, IpgD favors the elicitation of long-lasting local Ca2+ signals at Shigella invasion sites and converts Shigella-induced global oscillatory responses into erratic responses with atypical dynamics and amplitude. Furthermore, IpgD eventually inhibits InsP3-dependent responses during prolonged infection kinetics. IpgD thus acts as a pathogen regulator of the Ca2+ code implicated in a versatility of cell functions. Consistent with this function, IpgD prevents the Ca2+-dependent activation of calpain, thereby preserving the integrity of cell adhesion structures during the early stages of infection.
Collapse
Affiliation(s)
- Chun Hui Sun
- Equipe Communication Intercellulaire et Infections Microbiennes, Centre de Recherche Interdisciplinaire en Biologie (CIRB), Collège de France, Paris, France
- Institut National de la Santé et de la Recherche Médicale (Inserm) U1050, Paris, France
- Centre National de la Recherche Scientifique (CNRS) UMR7241, Paris, France
- MEMOLIFE Laboratory of excellence and Paris Sciences et Lettres, Paris, France
- Université Paris Sud, Orsay, France
- Inserm, UMRS1174, Orsay, France
| | - Benjamin Wacquier
- Unité de Chronobiologie Théorique, Université Libre de Bruxelles, Brussels, Belgium
| | - Daniel I Aguilar
- Equipe Communication Intercellulaire et Infections Microbiennes, Centre de Recherche Interdisciplinaire en Biologie (CIRB), Collège de France, Paris, France
- Institut National de la Santé et de la Recherche Médicale (Inserm) U1050, Paris, France
- Centre National de la Recherche Scientifique (CNRS) UMR7241, Paris, France
- MEMOLIFE Laboratory of excellence and Paris Sciences et Lettres, Paris, France
| | - Nathalie Carayol
- Equipe Communication Intercellulaire et Infections Microbiennes, Centre de Recherche Interdisciplinaire en Biologie (CIRB), Collège de France, Paris, France
- Institut National de la Santé et de la Recherche Médicale (Inserm) U1050, Paris, France
- Centre National de la Recherche Scientifique (CNRS) UMR7241, Paris, France
- MEMOLIFE Laboratory of excellence and Paris Sciences et Lettres, Paris, France
| | - Kevin Denis
- Equipe Communication Intercellulaire et Infections Microbiennes, Centre de Recherche Interdisciplinaire en Biologie (CIRB), Collège de France, Paris, France
- Institut National de la Santé et de la Recherche Médicale (Inserm) U1050, Paris, France
- Centre National de la Recherche Scientifique (CNRS) UMR7241, Paris, France
- MEMOLIFE Laboratory of excellence and Paris Sciences et Lettres, Paris, France
| | | | - Cesar Valencia-Gallardo
- Equipe Communication Intercellulaire et Infections Microbiennes, Centre de Recherche Interdisciplinaire en Biologie (CIRB), Collège de France, Paris, France
- Institut National de la Santé et de la Recherche Médicale (Inserm) U1050, Paris, France
- Centre National de la Recherche Scientifique (CNRS) UMR7241, Paris, France
- MEMOLIFE Laboratory of excellence and Paris Sciences et Lettres, Paris, France
| | - Ceren Simsek
- Equipe Communication Intercellulaire et Infections Microbiennes, Centre de Recherche Interdisciplinaire en Biologie (CIRB), Collège de France, Paris, France
- Institut National de la Santé et de la Recherche Médicale (Inserm) U1050, Paris, France
- Centre National de la Recherche Scientifique (CNRS) UMR7241, Paris, France
- MEMOLIFE Laboratory of excellence and Paris Sciences et Lettres, Paris, France
| | - Christophe Erneux
- Interdisciplinary Research Institute (IRIBHM), Université Libre de Bruxelles, Brussels, Belgium
| | - Alexandre Lehman
- Interdisciplinary Research Institute (IRIBHM), Université Libre de Bruxelles, Brussels, Belgium
| | - Jost Enninga
- Département de Biologie Cellulaire et Infection, Institut Pasteur, Unité de la Dynamique des Interactions Hôte-Pathogène, Paris, France
| | - Laurence Arbibe
- Equipe Plasticité du Génome et Infection, INSERM UMR_S1151 - CNRS UMR8253, Institut Necker Enfants Malades (INEM), Université Paris Descartes, Paris, France
| | - Philippe Sansonetti
- Département de Biologie Cellulaire et Infection, Unité de Pathogénie Microbienne Moléculaire, Paris, France
- Unité Inserm 1202, Institut Pasteur, Paris, France
- Collège de France, Paris, France
| | - Geneviève Dupont
- Unité de Chronobiologie Théorique, Université Libre de Bruxelles, Brussels, Belgium
| | | | - Guy Tran Van Nhieu
- Equipe Communication Intercellulaire et Infections Microbiennes, Centre de Recherche Interdisciplinaire en Biologie (CIRB), Collège de France, Paris, France
- Institut National de la Santé et de la Recherche Médicale (Inserm) U1050, Paris, France
- Centre National de la Recherche Scientifique (CNRS) UMR7241, Paris, France
- MEMOLIFE Laboratory of excellence and Paris Sciences et Lettres, Paris, France
| |
Collapse
|