DOCSLIB.ORG

NLRP10 Enhances Shigellainduced Proinflammatory Responses

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
NLRP10 Enhances Shigellainduced Proinflammatory Responses Cellular Microbiology (2012) doi:10.1111/j.1462-5822.2012.01822.x NLRP10 enhances Shigella-induced pro-inflammatory responses Katja Lautz,1 Anna Damm,1 Maureen Menning,1 Introduction Julia Wenger,2 Alexander C. Adam,3 Paola Zigrino,4 Elisabeth Kremmer5 and Thomas A. Kufer1* The innate immune system is the first line of defence 1Institute for Medical Microbiology, Immunology and against invading pathogens in mammals. By gaining Hygiene, University of Cologne, Cologne, Germany. access to the cellular cytoplasm, some bacteria and 2Department of Molecular Biology, University of viruses adopted to escape host innate immune surveil- Salzburg, Salzburg, Austria. lance by membrane standing pattern-recognition recep- 3Department of Pathology, University of Cologne, tors (PRRs) such as the Toll-like receptor family. To cope Cologne, Germany. with such intracellular residing pathogens, the host has 4Department of Dermatology, University of Cologne, evolved sophisticated detection systems. In particular Cologne, Germany. members of the nucleotide-binding domain leucine-rich 5Helmholtz Zentrum München, Institute of Molecular repeat containing family (NLR) have been shown to sense Immunology, Munich, Germany. such invasive bacteria and viruses. NLRs are a heteroge- neous class of 23 AAA+ ATPases in humans, which are characterized by a tripartite structural organization com- Summary prising an effector domain, a STAND type ATPase domain Members of the NLR family evolved as intracellular (called NACHT domain) and a series of leucine-rich sensors for bacterial and viral infection. However, repeats (LRRs) at the carboxyl-terminus (Fritz et al., our knowledge on the implication of most of the 2006; Schroder and Tschopp, 2010). NLRs are classified human NLR proteins in innate immune responses based on the nature of their amino-terminal effector still remains fragmentary. Here we characterized domain into a CARD-domain (NLRC) and a PYD-domain the role of human NLRP10 in bacterial infection. Our subfamily (NLRP), as well as in an ‘atypical’ effector data revealed that NLRP10 is a cytoplasmic local- domain family, comprising CIITA, NAIP, NLRX1, NLRC3 ized protein that positively contributes to innate and NLRC5. Most of our current knowledge of the biology immune responses induced by the invasive bacte- of NLRs derives from studies on a small number of NLRs rial pathogen Shigella flexneri. SiRNA-mediated including NOD1, NOD2 and NLRC4 as well as NLRP3 knock-down studies showed that NLRP10 contrib- and NLRP1 (Fritz et al., 2006, Schroder and Tschopp, utes to pro-inflammatory cytokine release triggered 2010). Seminal work has shown that NOD1 and NOD2 by Shigella in epithelial cells and primary dermal are sensors for bacterial infection and mediate inflam- fibroblasts, by influencing p38 and NF-kB activa- matory responses whereas NLRP1 and NLRP3 can form tion. This effect is dependent on the ATPase activity multimeric protein complexes, the so-called inflammas- of NLRP10 and its PYD domain. Mechanistically, omes, which allow processing of caspase-1 and subse- NLRP10 interacts with NOD1, a NLR that is pivotally quent release of IL-1b and IL-18 after sensing of PAMPs involved in sensing of invasive microbes, and both or danger signals (Martinon et al., 2002; Inohara et al., proteins are recruited to the bacterial entry point 2003; Girardin et al., 2003a; 2003b). However, the contri- at the plasma membrane. Moreover, NLRP10 phy- bution of other NLRs in bacteria-mediated innate immune sically interacts with downstream components responses remains less well defined. of the NOD1 signalling pathway, such as RIP2, Here we used the Gram-negative, invasive bacte- TAK1 and NEMO. Taken together, our data revealed rium Shigella flexneri as a well-characterized model a novel role of NLRP10 in innate immune re- system for bacterial infection. S. flexneri is a human sponses towards bacterial infection and suggest pathogen, responsible for endemic dysentery and dis- that NLRP10 functions as a scaffold for the forma- plays a complex interplay with the host cell (Schroeder tion of the NOD1–Nodosome. and Hilbi, 2008). S. flexneri has been shown to trigger pro-inflammatory responses in human epithelial cells by activating the NLR proteins NOD1 and NOD2 (Girardin Received 15 March, 2012; revised 18 May, 2012; accepted 26 May, 2012. *For correspondence. E-mail [email protected]; et al., 2001; Kufer et al., 2006). In macrophages NLRC4, Tel. (+49) 221 478 7279; Fax (+49) 221 478 7288. NAIP and NLRP3 contribute to Shigella-mediated host © 2012 Blackwell Publishing Ltd cellular microbiology 2 K. Lautz et al. responses as well by inducing a special type of caspase- NLRP10 and involves physical interactions with NOD1 1-dependent cell death (Damiano et al., 2004; Suzuki and the NOD1 signalling pathway components NEMO, et al., 2007; Willingham et al., 2007). The role of further RIP2 and TAK1. Conclusively, this defines a novel func- NLRs in Shigella-induced innate immune responses tion of NLRP10 in innate immune responses towards bac- however remains largely elusive. Of particular interest in terial infection and suggests that NLRP10 modulates our studies was NLRP10, the smallest of all human NLRs. signalling induced by the Nodosome complex. NLRP10 (Nalp10, alternatively named PAN5; NOD8; PYNOD; CLR11.1) is a prototypic member of the NLR family, although it lacks the LRRs (Ting et al., 2008), Results which are proposed to mediate detection of PAMPs. A NLRP10 is a cytoplasmic protein expressed in epithelial regulatory role for NLRP10 in innate immune responses and fibroblastic cells thus seems more likely than its function as a PRR. NLRP10 expression was proposed to be induced by In order to identify a suitable cellular model system for the PAMPs, such as LPS (Wang et al., 2004) and it was detailed functional characterization of NLRP10, we ana- shown that NLRP10 can inhibit ASC-mediated NF-kB acti- lysed the expression pattern of human NLRP10. While vation and IL-1b release in epithelial cells (Wang et al., human NLRP10 mRNA was shown to be expressed 2004; Kinoshita et al., 2005; Imamura et al., 2010). highly in heart, brain and muscle (Wang et al., 2004), Accordingly, transgenic mice that overexpress NLRP10 another study found that NLRP10 expression is highest in show a reduced IL-1b response towards bacterial and liver, small intestine and muscle (Lech et al., 2010). In PAMP stimulation and are less susceptible for endotoxic accordance with lack of detectable expression of NLRP10 shock (Imamura et al., 2010). These findings emphasize a in primary human CD14+ cells (Lech et al., 2010) we function of NLRP10 in innate immune responses and found that NLRP10 mRNA was not robustly detectable in suggest a role of NLRP10 in regulating inflammasome- the human myeloid cell line THP1 even after differentia- mediated responses. A physiological role for NLRP10 in tion to macrophage-like cells by PMA. Although NLRP10 immunity has been put forward by the characterization expression was slightly induced after additional stimula- of NLRP10-deficient mice. Surprisingly, these animals tion with LPS (Fig. 1A). Still, primary human peripheral display a migration defect of activated dendritic cells blood mononuclear cells (PBMCs) showed little expres- resulting in reduced adaptive immunity, whereas perito- sion of NLRP10 (Fig. 1A), as recently reported (Wang neal macrophages and bone marrow-derived dendritic et al., 2004). NLRP10 was found to be expressed in cells derived from NLRP10-deficient animals show normal human colon (Wang et al., 2004; Lech et al., 2010), we inflammasome activation (Eisenbarth et al., 2012). This therefore also tested NLRP10 mRNA expression in suggests that NLRP10 contributes to multiple cellular various human colon cell lines. This revealed that HT-29, functions. However, our understanding of the underlying CaCo2 and SW480 cells showed expression of NLRP10, molecular mechanisms remains largely elusive. although we found that epithelial HeLa cells had a much Here we show that NLRP10 contributes to pro- higher basal expression of NLRP10 (Fig. 1A). In contrast, inflammatory innate immune responses towards the inva- human embryonic kidney cells (HEK293T) showed no sive human pathogen S. flexneri. This effect is dependent detectable basal expression of NLPR10 transcript on a functional ATPase domain and the PYD domain of (Fig. 1A). Of note, primary human dermal fibroblasts Fig. 1. NLRP10 is a cytosolic protein predominantly expressed in human epidermis. A. Expression of NLRP10 mRNA in different human cell lines and primary human PBMCs, analysed by RT-PCR. Amplification of GAPDH served as control (lower panels). THP1 cells were incubated in 100 nM PMA for 24 h and exposed to LPS (100 ng ml-1) 4 h prior to the isolation of RNA where indicated. B. Expression of NLRP10 mRNA in human dermis and epidermis samples, tested by RT-PCR. N: negative control; P: plasmid positive control. Results are representative of three donors. C. Characterization of NLRP10-specific monoclonal antibody 4B4 in lysates from HEK293T transfected with NLRP10 or empty plasmid. Detection with a FLAG-specific antibody served as control. D. Immunohistochemical staining of healthy human skin tissue. Endogenous NLRP10 was detected with anti-NLRP10 4B4 (left panel). Control staining was conducted with a matched isotope (right panel). The result is representative of two donors. E. Indirect immunofluorescence micrographs of HeLa (left panel) and primary human dermal fibroblasts (right panel). Ectopically expressed FLAG-NLRP10 was detected by an anti-FLAG antibody (green), merge with staining for DNA (blue) is shown (left panel). Endogenous NLRP10 was detected with the 8H2 antibody (red) in primary human dermal fibroblasts. Merge with staining for DNA (blue) and actin (green) is shown. Data are representative for two donors. F. Immunoblot analysis of the primary epidermal fibroblasts treated for 72 h with an NLRP10-specific siRNA or a non-targeting control siRNA. Detection of endogenous NLRP10 in the same cells and with the same antibody used in (E) is shown. Probing for a-tubulin served as control for equal loading.
Load more

Recommended publications
  • The Role of Vimentin and the NLRP3 Inflammasome in Influenza a Infection
    The Role of Vimentin and the NLRP3 Inflammasome in Influenza A Infection A Senior Thesis Presented to The Faculty of the Department of Molecular Biology, Colorado College By Maggie Turner Bachelor of Arts Degree in Molecular Biology April 28, 2017 ________________________ Dr. Olivia Hatton Primary Thesis Advisor __________________________ Dr. Sara Hanson Secondary Thesis Advisor ABSTRACT Infection with Influenza A virus (IAV) continues to cause morbidity and mortality in children across the globe, in part due to the excessive inflammatory response during pathogen clearance. Using a murine model of IAV infection, this study focuses on the role of the innate immune system in IAV infection through the scope of NLRP3 inflammasome protein activation and assembly. We were able to detect the presence of the NLRP3-inflammasome target proteins ASC, Pro-caspase-1, NLRP3, RIG-1, and IL- 1β in both juvenile and adult mice. Notably, we found significantly increased levels of ASC and RIG-1 protein in juveniles compared to adults. This suggests that ASC and RIG-1 are related to the observed excessive inflammatory response upon IAV infection in juveniles. To examine NLRP3-inflammasome assembly, we created multiple mutant constructs of the inflammasome scaffolding protein Vimentin as well as vimentin-/- cells. IL-1β production was greatly inhibited in vimentin-/- cells compared to the wild type upon activation of the NLRP3 inflammasome. The same trend was seen when only the head region of the protein was present. We suggest that the intermediate filament (IF) Vimentin serves as a protein scaffold for inflammasome assembly, and that expression of Vimentin is a necessary checkpoint in the innate immune response.
    [Show full text]
  • The Expression of NOD2, NLRP3 and NLRC5 and Renal Injury in Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis
    Wang et al. J Transl Med (2019) 17:197 https://doi.org/10.1186/s12967-019-1949-5 Journal of Translational Medicine RESEARCH Open Access The expression of NOD2, NLRP3 and NLRC5 and renal injury in anti-neutrophil cytoplasmic antibody-associated vasculitis Luo‑Yi Wang1,2,3, Xiao‑Jing Sun1,2,3, Min Chen1,2,3* and Ming‑Hui Zhao1,2,3,4 Abstract Background: Nucleotide‑binding oligomerization domain (NOD)‑like receptors (NLRs) are intracellular sensors of pathogens and molecules from damaged cells to regulate the infammatory response in the innate immune system. Emerging evidences suggested a potential role of NLRs in anti‑neutrophil cytoplasmic antibody (ANCA)‑associated vasculitis (AAV). This study aimed to investigate the expression of nucleotide‑binding oligomerization domain con‑ taining protein 2 (NOD2), NOD‑like receptor family pyrin domain containing 3 (NLRP3) and NOD‑like receptor family CARD domain containing 5 (NLRC5) in kidneys of AAV patients, and further explored their associations with clinical and pathological parameters. Methods: Thirty‑four AAV patients in active stage were recruited. Their renal specimens were processed with immu‑ nohistochemistry to assess the expression of three NLRs, and with double immunofuorescence to detect NLRs on intrinsic and infltrating cells. Analysis of gene expression was also adopted in cultured human podocytes. The associa‑ tions between expression of NLRs and clinicopathological parameters were analyzed. Results: The expression of NOD2, NLRP3 and NLRC5 was signifcantly higher in kidneys from AAV patients than those from normal controls, minimal change disease or class IV lupus nephritis. These NLRs co‑localized with podocytes and infltrating infammatory cells.
    [Show full text]
  • Role of Nlrs in the Regulation of Type I Interferon Signaling, Host Defense and Tolerance to Inflammation
    International Journal of Molecular Sciences Review Role of NLRs in the Regulation of Type I Interferon Signaling, Host Defense and Tolerance to Inflammation Ioannis Kienes 1, Tanja Weidl 1, Nora Mirza 1, Mathias Chamaillard 2 and Thomas A. Kufer 1,* 1 Department of Immunology, Institute for Nutritional Medicine, University of Hohenheim, 70599 Stuttgart, Germany; [email protected] (I.K.); [email protected] (T.W.); [email protected] (N.M.) 2 University of Lille, Inserm, U1003, F-59000 Lille, France; [email protected] * Correspondence: [email protected] Abstract: Type I interferon signaling contributes to the development of innate and adaptive immune responses to either viruses, fungi, or bacteria. However, amplitude and timing of the interferon response is of utmost importance for preventing an underwhelming outcome, or tissue damage. While several pathogens evolved strategies for disturbing the quality of interferon signaling, there is growing evidence that this pathway can be regulated by several members of the Nod-like receptor (NLR) family, although the precise mechanism for most of these remains elusive. NLRs consist of a family of about 20 proteins in mammals, which are capable of sensing microbial products as well as endogenous signals related to tissue injury. Here we provide an overview of our current understanding of the function of those NLRs in type I interferon responses with a focus on viral infections. We discuss how NLR-mediated type I interferon regulation can influence the development of auto-immunity and the immune response to infection. Citation: Kienes, I.; Weidl, T.; Mirza, Keywords: NOD-like receptors; Interferons; innate immunity; immune regulation; type I interferon; N.; Chamaillard, M.; Kufer, T.A.
    [Show full text]
  • Bayesian Hierarchical Modeling of High-Throughput Genomic Data with Applications to Cancer Bioinformatics and Stem Cell Differentiation
    BAYESIAN HIERARCHICAL MODELING OF HIGH-THROUGHPUT GENOMIC DATA WITH APPLICATIONS TO CANCER BIOINFORMATICS AND STEM CELL DIFFERENTIATION by Keegan D. Korthauer A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Statistics) at the UNIVERSITY OF WISCONSIN–MADISON 2015 Date of final oral examination: 05/04/15 The dissertation is approved by the following members of the Final Oral Committee: Christina Kendziorski, Professor, Biostatistics and Medical Informatics Michael A. Newton, Professor, Statistics Sunduz Kele¸s,Professor, Biostatistics and Medical Informatics Sijian Wang, Associate Professor, Biostatistics and Medical Informatics Michael N. Gould, Professor, Oncology © Copyright by Keegan D. Korthauer 2015 All Rights Reserved i in memory of my grandparents Ma and Pa FL Grandma and John ii ACKNOWLEDGMENTS First and foremost, I am deeply grateful to my thesis advisor Christina Kendziorski for her invaluable advice, enthusiastic support, and unending patience throughout my time at UW-Madison. She has provided sound wisdom on everything from methodological principles to the intricacies of academic research. I especially appreciate that she has always encouraged me to eke out my own path and I attribute a great deal of credit to her for the successes I have achieved thus far. I also owe special thanks to my committee member Professor Michael Newton, who guided me through one of my first collaborative research experiences and has continued to provide key advice on my thesis research. I am also indebted to the other members of my thesis committee, Professor Sunduz Kele¸s,Professor Sijian Wang, and Professor Michael Gould, whose valuable comments, questions, and suggestions have greatly improved this dissertation.
    [Show full text]
  • Cytotoxic T Cells Class I- Dependent Lymphocyte Killing by NLRC5 Deficiency Selectively Impairs
    The Journal of Immunology NLRC5 Deficiency Selectively Impairs MHC Class I- Dependent Lymphocyte Killing by Cytotoxic T Cells Francesco Staehli,* Kristina Ludigs,* Leonhard X. Heinz,† Queralt Seguı´n-Este´vez,‡ Isabel Ferrero,x Marion Braun,x Kate Schroder,{ Manuele Rebsamen,† Aubry Tardivel,* Chantal Mattmann,* H. Robson MacDonald,x Pedro Romero,x Walter Reith,‡ Greta Guarda,*,1 and Ju¨rg Tschopp*,1,2 Nucleotide-binding oligomerization domain-like receptors (NLRs) are intracellular proteins involved in innate-driven inflamma- tory responses. The function of the family member NLR caspase recruitment domain containing protein 5 (NLRC5) remains a matter of debate, particularly with respect to NF-kB activation, type I IFN, and MHC I expression. To address the role of NLRC5, we generated Nlrc5-deficient mice (Nlrc5D/D). In this article we show that these animals exhibit slightly decreased CD8+ T cell percentages, a phenotype compatible with deregulated MHC I expression. Of interest, NLRC5 ablation only mildly affected MHC I expression on APCs and, accordingly, Nlrc5D/D macrophages efficiently primed CD8+ T cells. In contrast, NLRC5 deficiency dramatically impaired basal expression of MHC I in T, NKT, and NK lymphocytes. NLRC5 was sufficient to induce MHC I expression in a human lymphoid cell line, requiring both caspase recruitment and LRR domains. Moreover, endogenous NLRC5 localized to the nucleus and occupied the proximal promoter region of H-2 genes. Consistent with downregulated MHC I expression, the elimination of Nlrc5D/D lymphocytes by cytotoxic T cells was markedly reduced and, in addition, we observed low NLRC5 expression in several murine and human lymphoid-derived tumor cell lines.
    [Show full text]
  • Scholarly Commons NLRX1 Modulates Differentially NLRP3
    University of the Pacific Scholarly Commons Dugoni School of Dentistry Faculty Articles Arthur A. Dugoni School of Dentistry 10-1-2018 NLRX1 modulates differentially NLRP3 inflammasome activation and NF-κB signaling during Fusobacterium nucleatum infection Shu Chen Hung University of the Pacific Arthur A. Dugoni School of Dentistry Pei Rong Huang Chang Gung University Cassio Luiz Coutinho Almeida-Da-Silva University of the Pacific Arthur A. Dugoni School of Dentistry, [email protected] Kalina R. Atanasova University of Florida Ozlem Yilmaz Medical University of South Carolina See next page for additional authors Follow this and additional works at: https://scholarlycommons.pacific.edu/dugoni-facarticles Part of the Dentistry Commons Recommended Citation Hung, S., Huang, P., Almeida-Da-Silva, C. L., Atanasova, K. R., Yilmaz, O., & Ojcius, D. M. (2018). NLRX1 modulates differentially NLRP3 inflammasome activation and NF-κB signaling during Fusobacterium nucleatum infection. Microbes and Infection, 20(9-10), 615–625. DOI: 10.1016/j.micinf.2017.09.014 https://scholarlycommons.pacific.edu/dugoni-facarticles/705 This Article is brought to you for free and open access by the Arthur A. Dugoni School of Dentistry at Scholarly Commons. It has been accepted for inclusion in Dugoni School of Dentistry Faculty Articles by an authorized administrator of Scholarly Commons. For more information, please contact [email protected]. Authors Shu Chen Hung, Pei Rong Huang, Cassio Luiz Coutinho Almeida-Da-Silva, Kalina R. Atanasova, Ozlem Yilmaz, and David M. Ojcius This article is available at Scholarly Commons: https://scholarlycommons.pacific.edu/dugoni-facarticles/705 Version of Record: https://www.sciencedirect.com/science/article/pii/S1286457917301582 Manuscript_dd7f93413c97aff4865d54242a8b21e7 1 NLRX1 modulates differentially NLRP3 inflammasome activation 2 and NF-κB signaling during Fusobacterium nucleatum infection 3 4 5 Shu-Chen Hung 1, *, Pei-Rong Huang 2, Cássio Luiz Coutinho Almeida-da-Silva 1,3 , 6 Kalina R.
    [Show full text]
  • Review Article New Insights Into Nod-Like Receptors (Nlrs) in Liver Diseases
    Int J Physiol Pathophysiol Pharmacol 2018;10(1):1-16 www.ijppp.org /ISSN:1944-8171/IJPPP0073857 Review Article New insights into Nod-like receptors (NLRs) in liver diseases Tao Xu1,2*, Yan Du1,2*, Xiu-Bin Fang3, Hao Chen1,2, Dan-Dan Zhou1,2, Yang Wang1,2, Lei Zhang1,2 1School of Pharmacy, Anhui Medical University, Hefei 230032, China; 2Institute for Liver Disease of Anhui Medi- cal University, Anhui Medical University, Hefei 230032, China; 3The Second Affiliated Hospital of Anhui Medical University, Fu Rong Road, Hefei 230601, Anhui Province, China. *Equal contributors. Received February 1, 2018; Accepted February 19, 2018; Epub March 10, 2018; Published March 20, 2018 Abstract: Activation of inflammatory signaling pathways is of central importance in the pathogenesis of alcoholic liver disease (ALD) and nonalcoholic steatohepatitis (NASH). Nod-like receptors (NLRs) are intracellular innate im- mune sensors of microbes and danger signals that control multiple aspects of inflammatory responses. Recent studies demonstrated that NLRs are expressed and activated in innate immune cells as well as in parenchymal cells in the liver. For example, NLRP3 signaling is involved in liver ischemia-reperfusion (I/R) injury and silencing of NLRP3 can protect the liver from I/R injury. In this article, we review the evidence that highlights the critical impor- tance of NLRs in the prevalent liver diseases. The significance of NLR-induced intracellular signaling pathways and cytokine production is also evaluated. Keywords: Nod-like receptors (NLRs), liver diseases, NLRP3 Introduction nonalcoholic steatohepatitis (NASH) [13], Non- alcoholic fatty liver disease (NAFLD) [14], Ace- The liver is the first organ exposed to orally taminophen (N-acetyl-para-aminophenol) he- administered xenobiotics after absorption from patotoxicity [15], viral hepatitis, primary biliary the intestine, and it is a major site of biotrans- cirrhosis, sclerosing cholangitis, paracetamol- formation and metabolism [1, 2].
    [Show full text]
  • Post-Transcriptional Inhibition of Luciferase Reporter Assays
    THE JOURNAL OF BIOLOGICAL CHEMISTRY VOL. 287, NO. 34, pp. 28705–28716, August 17, 2012 © 2012 by The American Society for Biochemistry and Molecular Biology, Inc. Published in the U.S.A. Post-transcriptional Inhibition of Luciferase Reporter Assays by the Nod-like Receptor Proteins NLRX1 and NLRC3* Received for publication, December 12, 2011, and in revised form, June 18, 2012 Published, JBC Papers in Press, June 20, 2012, DOI 10.1074/jbc.M111.333146 Arthur Ling‡1,2, Fraser Soares‡1,2, David O. Croitoru‡1,3, Ivan Tattoli‡§, Leticia A. M. Carneiro‡4, Michele Boniotto¶, Szilvia Benko‡5, Dana J. Philpott§, and Stephen E. Girardin‡6 From the Departments of ‡Laboratory Medicine and Pathobiology and §Immunology, University of Toronto, Toronto M6G 2T6, Canada, and the ¶Modulation of Innate Immune Response, INSERM U1012, Paris South University School of Medicine, 63, rue Gabriel Peri, 94276 Le Kremlin-Bicêtre, France Background: A number of Nod-like receptors (NLRs) have been shown to inhibit signal transduction pathways using luciferase reporter assays (LRAs). Results: Overexpression of NLRX1 and NLRC3 results in nonspecific post-transcriptional inhibition of LRAs. Conclusion: LRAs are not a reliable technique to assess the inhibitory function of NLRs. Downloaded from Significance: The inhibitory role of NLRs on specific signal transduction pathways needs to be reevaluated. Luciferase reporter assays (LRAs) are widely used to assess the Nod-like receptors (NLRs)7 represent an important class of activity of specific signal transduction pathways. Although pow- intracellular pattern recognition molecules (PRMs), which are erful, rapid and convenient, this technique can also generate implicated in the detection and response to microbe- and dan- www.jbc.org artifactual results, as revealed for instance in the case of high ger-associated molecular patterns (MAMPs and DAMPs), throughput screens of inhibitory molecules.
    [Show full text]
  • NOD-Like Receptors in the Eye: Uncovering Its Role in Diabetic Retinopathy
    International Journal of Molecular Sciences Review NOD-like Receptors in the Eye: Uncovering Its Role in Diabetic Retinopathy Rayne R. Lim 1,2,3, Margaret E. Wieser 1, Rama R. Ganga 4, Veluchamy A. Barathi 5, Rajamani Lakshminarayanan 5 , Rajiv R. Mohan 1,2,3,6, Dean P. Hainsworth 6 and Shyam S. Chaurasia 1,2,3,* 1 Ocular Immunology and Angiogenesis Lab, University of Missouri, Columbia, MO 652011, USA; [email protected] (R.R.L.); [email protected] (M.E.W.); [email protected] (R.R.M.) 2 Department of Biomedical Sciences, University of Missouri, Columbia, MO 652011, USA 3 Ophthalmology, Harry S. Truman Memorial Veterans’ Hospital, Columbia, MO 652011, USA 4 Surgery, University of Missouri, Columbia, MO 652011, USA; [email protected] 5 Singapore Eye Research Institute, Singapore 169856, Singapore; [email protected] (V.A.B.); [email protected] (R.L.) 6 Mason Eye Institute, School of Medicine, University of Missouri, Columbia, MO 652011, USA; [email protected] * Correspondence: [email protected]; Tel.: +1-573-882-3207 Received: 9 December 2019; Accepted: 27 January 2020; Published: 30 January 2020 Abstract: Diabetic retinopathy (DR) is an ocular complication of diabetes mellitus (DM). International Diabetic Federations (IDF) estimates up to 629 million people with DM by the year 2045 worldwide. Nearly 50% of DM patients will show evidence of diabetic-related eye problems. Therapeutic interventions for DR are limited and mostly involve surgical intervention at the late-stages of the disease. The lack of early-stage diagnostic tools and therapies, especially in DR, demands a better understanding of the biological processes involved in the etiology of disease progression.
    [Show full text]
  • Pattern Recognition Receptors in Health and Diseases
    Signal Transduction and Targeted Therapy www.nature.com/sigtrans REVIEW ARTICLE OPEN Pattern recognition receptors in health and diseases Danyang Li1,2 and Minghua Wu1,2 Pattern recognition receptors (PRRs) are a class of receptors that can directly recognize the specific molecular structures on the surface of pathogens, apoptotic host cells, and damaged senescent cells. PRRs bridge nonspecific immunity and specific immunity. Through the recognition and binding of ligands, PRRs can produce nonspecific anti-infection, antitumor, and other immunoprotective effects. Most PRRs in the innate immune system of vertebrates can be classified into the following five types based on protein domain homology: Toll-like receptors (TLRs), nucleotide oligomerization domain (NOD)-like receptors (NLRs), retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs), C-type lectin receptors (CLRs), and absent in melanoma-2 (AIM2)-like receptors (ALRs). PRRs are basically composed of ligand recognition domains, intermediate domains, and effector domains. PRRs recognize and bind their respective ligands and recruit adaptor molecules with the same structure through their effector domains, initiating downstream signaling pathways to exert effects. In recent years, the increased researches on the recognition and binding of PRRs and their ligands have greatly promoted the understanding of different PRRs signaling pathways and provided ideas for the treatment of immune-related diseases and even tumors. This review describes in detail the history, the structural characteristics, ligand recognition mechanism, the signaling pathway, the related disease, new drugs in clinical trials and clinical therapy of different types of PRRs, and discusses the significance of the research on pattern recognition mechanism for the treatment of PRR-related diseases.
    [Show full text]
  • Post-Translational Regulation of Inflammasomes
    OPEN Cellular & Molecular Immunology (2017) 14, 65–79 & 2017 CSI and USTC All rights reserved 2042-0226/17 www.nature.com/cmi REVIEW Post-translational regulation of inflammasomes Jie Yang1,2, Zhonghua Liu1 and Tsan Sam Xiao1 Inflammasomes play essential roles in immune protection against microbial infections. However, excessive inflammation is implicated in various human diseases, including autoinflammatory syndromes, diabetes, multiple sclerosis, cardiovascular disorders and neurodegenerative diseases. Therefore, precise regulation of inflammasome activities is critical for adequate immune protection while limiting collateral tissue damage. In this review, we focus on the emerging roles of post-translational modifications (PTMs) that regulate activation of the NLRP3, NLRP1, NLRC4, AIM2 and IFI16 inflammasomes. We anticipate that these types of PTMs will be identified in other types of and less well-characterized inflammasomes. Because these highly diverse and versatile PTMs shape distinct inflammatory responses in response to infections and tissue damage, targeting the enzymes involved in these PTMs will undoubtedly offer opportunities for precise modulation of inflammasome activities under various pathophysiological conditions. Cellular & Molecular Immunology (2017) 14, 65–79; doi:10.1038/cmi.2016.29; published online 27 June 2016 Keywords: inflammasome; phosphorylation; post-translational modifications; ubiquitination INTRODUCTION upstream sensor molecules through its PYD domain and The innate immune system relies on pattern recognition downstream
    [Show full text]
  • ATP-Binding and Hydrolysis in Inflammasome Activation
    molecules Review ATP-Binding and Hydrolysis in Inflammasome Activation Christina F. Sandall, Bjoern K. Ziehr and Justin A. MacDonald * Department of Biochemistry & Molecular Biology, Cumming School of Medicine, University of Calgary, 3280 Hospital Drive NW, Calgary, AB T2N 4Z6, Canada; [email protected] (C.F.S.); [email protected] (B.K.Z.) * Correspondence: [email protected]; Tel.: +1-403-210-8433 Academic Editor: Massimo Bertinaria Received: 15 September 2020; Accepted: 3 October 2020; Published: 7 October 2020 Abstract: The prototypical model for NOD-like receptor (NLR) inflammasome assembly includes nucleotide-dependent activation of the NLR downstream of pathogen- or danger-associated molecular pattern (PAMP or DAMP) recognition, followed by nucleation of hetero-oligomeric platforms that lie upstream of inflammatory responses associated with innate immunity. As members of the STAND ATPases, the NLRs are generally thought to share a similar model of ATP-dependent activation and effect. However, recent observations have challenged this paradigm to reveal novel and complex biochemical processes to discern NLRs from other STAND proteins. In this review, we highlight past findings that identify the regulatory importance of conserved ATP-binding and hydrolysis motifs within the nucleotide-binding NACHT domain of NLRs and explore recent breakthroughs that generate connections between NLR protein structure and function. Indeed, newly deposited NLR structures for NLRC4 and NLRP3 have provided unique perspectives on the ATP-dependency of inflammasome activation. Novel molecular dynamic simulations of NLRP3 examined the active site of ADP- and ATP-bound models. The findings support distinctions in nucleotide-binding domain topology with occupancy of ATP or ADP that are in turn disseminated on to the global protein structure.
    [Show full text]