1
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Chiu TY, Lazar DC, Wang WW, Wozniak JM, Jadhav AM, Li W, Gazaniga N, Theofilopoulos AN, Teijaro JR, Parker CG. Chemoproteomic development of SLC15A4 inhibitors with anti-inflammatory activity. Nat Chem Biol 2024; 20:1000-1011. [PMID: 38191941 PMCID: PMC11228132 DOI: 10.1038/s41589-023-01527-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 12/14/2023] [Indexed: 01/10/2024]
Abstract
SLC15A4 is an endolysosome-resident transporter linked with autoinflammation and autoimmunity. Specifically, SLC15A4 is critical for Toll-like receptors (TLRs) 7-9 as well as nucleotide-binding oligomerization domain-containing protein (NOD) signaling in several immune cell subsets. Notably, SLC15A4 is essential for the development of systemic lupus erythematosus in murine models and is associated with autoimmune conditions in humans. Despite its therapeutic potential, the availability of quality chemical probes targeting SLC15A4 functions is limited. In this study, we used an integrated chemical proteomics approach to develop a suite of chemical tools, including first-in-class functional inhibitors, for SLC15A4. We demonstrate that these inhibitors suppress SLC15A4-mediated endolysosomal TLR and NOD functions in a variety of human and mouse immune cells; we provide evidence of their ability to suppress inflammation in vivo and in clinical settings; and we provide insights into their mechanism of action. Our findings establish SLC15A4 as a druggable target for the treatment of autoimmune and autoinflammatory conditions.
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Affiliation(s)
- Tzu-Yuan Chiu
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | - Daniel C Lazar
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Wesley W Wang
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | - Jacob M Wozniak
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | - Appaso M Jadhav
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | - Weichao Li
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | - Nathalia Gazaniga
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | | | - John R Teijaro
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA.
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2
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Miyake K, Shibata T, Fukui R, Murakami Y, Sato R, Hiranuma R. Endosomal Toll-Like Receptors as Therapeutic Targets for Autoimmune Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1444:97-108. [PMID: 38467975 DOI: 10.1007/978-981-99-9781-7_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
Nucleic acid (NA)-sensing Toll-like receptors (TLRs) reside in the endosomal compartment of innate immune cells, such as macrophages and dendritic cells. NAs transported to the endosomal compartment are degraded by DNases and RNases. Degradation products, including single-stranded DNA, oligoRNA, and nucleosides, are recognized by TLR7, TLR8, and TLR9 to drive the defense responses against pathogens. NA degradation influences endosomal TLR responses by generating and degrading TLR ligands. TLR ligand accumulation because of impaired NA degradation causes constitutive TLR activation, leading to autoinflammatory and autoimmune diseases. Furthermore, some genes associated with these diseases promote endosomal TLR responses. Therefore, endosomal TLRs are promising therapeutic targets for TLR-mediated inflammatory diseases, and novel drugs targeting TLRs are being developed.
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Affiliation(s)
- Kensuke Miyake
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.
| | - Takuma Shibata
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Ryutaro Fukui
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Yusuke Murakami
- Faculty of Pharmacy, Department of Pharmaceutical Sciences and Research Institute of Pharmaceutical Sciences, Musashino University, Tokyo, Japan
| | - Ryota Sato
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Ryosuke Hiranuma
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
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3
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Song HS, Park S, Huh JW, Lee YR, Jung DJ, Yang C, Kim SH, Kim HM, Kim YM. N-glycosylation of UNC93B1 at a Specific Asparagine Residue Is Required for TLR9 Signaling. Front Immunol 2022; 13:875083. [PMID: 35874766 PMCID: PMC9301129 DOI: 10.3389/fimmu.2022.875083] [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: 02/13/2022] [Accepted: 05/27/2022] [Indexed: 11/29/2022] Open
Abstract
Toll-like receptors (TLRs) play critical roles in the first line of host defense against pathogens through recognition of pathogen-associated molecular patterns and initiation of the innate immune responses. The proper localization of TLRs in specific subcellular compartments is crucial for their ligand recognition and downstream signaling to ensure appropriate responses against pathogens while avoiding erroneous or excessive activation. Several TLRs, including TLR7 and TLR9 but not TLR4, depend on UNC93B1 for their proper intracellular localization and signaling. Accumulating evidence suggest that UNC93B1 differentially regulates its various client TLRs, but the specific mechanisms by which UNC93B1 controls individual TLRs are not well understood. Protein N-glycosylation is one of the most frequent and important post-translational modification that occurs in membrane-localized or secreted proteins. UNC93B1 was previously shown to be glycosylated at Asn251 and Asn272 residues. In this study, we investigated whether N-glycosylation of UNC93B1 affects its function by comparing wild type and glycosylation-defective mutant UNC93B1 proteins. It was found that glycosylation of Asn251 and Asn272 residues can occur independently of each other and mutation of neither N251Q or N272Q in UNC93B1 altered expression and localization of UNC93B1 and TLR9. In contrast, CpG DNA-stimulated TLR9 signaling was severely inhibited in cells expressing UNC93B1(N272Q), but not in cells with UNC93B1(N251Q). Further, it was found that glycosylation at Asn272 of UNC93B1 is essential for the recruitment of MyD88 to TLR9 and the subsequent downstream signaling. On the other hand, the defective glycosylation at Asn272 did not affect TLR7 signaling. Collectively, these data demonstrate that the glycosylation at a specific asparagine residue of UNC93B1 is required for TLR9 signaling and the glycosylation status of UNC93B1 differently affects activation of TLR7 and TLR9.
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Affiliation(s)
- Hyun-Sup Song
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
| | - Soeun Park
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
| | - Ji-Won Huh
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul, South Korea
| | - Yu-Ran Lee
- Division of Integrative Biosciences and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang, South Korea
| | - Da-Jung Jung
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
| | - Chorong Yang
- Division of Integrative Biosciences and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang, South Korea
| | - So Hyun Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
- Center for Biomolecular & Cellular Structure, Institute for Basic Science (IBS), Daejeon, South Korea
| | - Ho Min Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
- Center for Biomolecular & Cellular Structure, Institute for Basic Science (IBS), Daejeon, South Korea
| | - You-Me Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
- *Correspondence: You-Me Kim,
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4
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Miyake K, Shibata T, Fukui R, Sato R, Saitoh SI, Murakami Y. Nucleic Acid Sensing by Toll-Like Receptors in the Endosomal Compartment. Front Immunol 2022; 13:941931. [PMID: 35812450 PMCID: PMC9259784 DOI: 10.3389/fimmu.2022.941931] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 05/27/2022] [Indexed: 11/24/2022] Open
Abstract
Toll-like receptors (TLRs) respond to pathogen constituents, such as microbial lipids and nucleic acids (NAs). TLRs recognize NAs in endosomal compartments. Structural and functional studies have shown that recognition of NAs by TLRs depends on NA processing by RNases and DNases. DNase II-dependent DNA degradation is required for TLR9 responses to single-stranded DNAs, whereas RNase T2-dependent RNA degradation enables TLR7 and TLR8 to respond to nucleosides and oligoribonucleotides. In contrast, RNases and DNases negatively regulate TLR responses by degrading their ligands. RNase T2 negatively regulates TLR3 responses to degrading the TLR3 ligand double-stranded RNAs. Therefore, NA metabolism in the endosomal compartments affects the endosomal TLR responses. Dysregulation of NA metabolism in the endosomal compartment drives the TLR-dependent pathologies in human diseases.
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Affiliation(s)
- Kensuke Miyake
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Minato-ku, Japan
- *Correspondence: Kensuke Miyake,
| | - Takuma Shibata
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Minato-ku, Japan
| | - Ryutaro Fukui
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Minato-ku, Japan
| | - Ryota Sato
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Minato-ku, Japan
| | - Shin-Ichiroh Saitoh
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Minato-ku, Japan
| | - Yusuke Murakami
- Faculty of Pharmacy, Department of Pharmaceutical Sciences and Research Institute of Pharmaceutical Sciences, Musashino University, Tokyo, Japan
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5
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Morell M, Varela N, Castillejo-López C, Coppard C, Luque MJ, Wu YY, Martín-Morales N, Pérez-Cózar F, Gómez-Hernández G, Kumar R, O'Valle F, Alarcón-Riquelme ME, Marañón C. SIDT1 plays a key role in type I IFN responses to nucleic acids in plasmacytoid dendritic cells and mediates the pathogenesis of an imiquimod-induced psoriasis model. EBioMedicine 2022; 76:103808. [PMID: 35065421 PMCID: PMC8784643 DOI: 10.1016/j.ebiom.2021.103808] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 12/23/2021] [Accepted: 12/23/2021] [Indexed: 11/29/2022] Open
Abstract
Background Type I IFN (IFN-I) is a family of cytokines involved in the pathogenesis of autoimmune and autoinflammatory diseases such as psoriasis. SIDT1 is an ER-resident protein expressed in the lymphoid lineage, and involved in anti-viral IFN-I responses in vivo, through an unclear mechanism. Herein we have dissected the role of SIDT1 in the natural IFN-producing cells, the plasmacytoid dendritic cells (pDC). Methods The function of SIDT1 in pDC was determined by silencing its expression in human primary pDC and GEN2.2 cell line. SIDT1 role in vivo was assessed using the imiquimod-induced psoriasis model in the SIDT1-deficient mice (sidt1−/−). Findings Silencing of SIDT1 in GEN2.2 led to a blockade of the IFN-I response after stimulation of TLR7 and TLR9, without affecting the pro-inflammatory responses or upregulation of maturation markers. We found that SIDT1 migrates from the ER to the endosomal and lysosomal compartments together with TLR9 after CpG stimulation, participating in the access of the TLR9-CpG complex to lysosome-related vesicles, and therefore mediating the activation of TBK1 and the nuclear migration of IRF7, but not of NF-κB. sidt1−/− mice showed a significant decrease in severity parameters of the imiquimod-induced acute psoriasis-like model, associated with a decrease in the production of IFN-I and IFN-dependent chemokines. Interpretation Our findings indicate that SIDT1 is at the cross-road between the IFN-I and the proinflammatory pathways and constitutes a promising drug target for psoriasis and other diseases mediated by IFN-I responses. Funding This work was supported by the Consejería de Salud y Familias de la Junta de Andalucía (PIER_S1149 and C2_S0050) and Instituto de Salud Carlos III (PI18/00082 and PI21/01151), partly supported by European FEDER funds, and prior funding to MEAR from the Alliance for Lupus Research and the Swedish Research Council.
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Affiliation(s)
- María Morell
- GENYO, Centre for Genomics and Oncological Research. Pfizer, University of Granada, Andalusian Regional Government, Avda Ilustración 114, PTS Granada 18016, Spain
| | - Nieves Varela
- GENYO, Centre for Genomics and Oncological Research. Pfizer, University of Granada, Andalusian Regional Government, Avda Ilustración 114, PTS Granada 18016, Spain
| | - Casimiro Castillejo-López
- GENYO, Centre for Genomics and Oncological Research. Pfizer, University of Granada, Andalusian Regional Government, Avda Ilustración 114, PTS Granada 18016, Spain
| | - Céline Coppard
- GENYO, Centre for Genomics and Oncological Research. Pfizer, University of Granada, Andalusian Regional Government, Avda Ilustración 114, PTS Granada 18016, Spain
| | - María José Luque
- GENYO, Centre for Genomics and Oncological Research. Pfizer, University of Granada, Andalusian Regional Government, Avda Ilustración 114, PTS Granada 18016, Spain
| | - Ying-Yu Wu
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Natividad Martín-Morales
- Department of Pathology, School of Medicine, University of Granada, Spain; Department of Oral Surgery, School of Dentistry, University of Granada, Spain
| | - Francisco Pérez-Cózar
- GENYO, Centre for Genomics and Oncological Research. Pfizer, University of Granada, Andalusian Regional Government, Avda Ilustración 114, PTS Granada 18016, Spain
| | - Gonzalo Gómez-Hernández
- GENYO, Centre for Genomics and Oncological Research. Pfizer, University of Granada, Andalusian Regional Government, Avda Ilustración 114, PTS Granada 18016, Spain
| | - Ramesh Kumar
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Francisco O'Valle
- Department of Pathology, School of Medicine, University of Granada, Spain; Ibs.GRANADA and IBIMER Institutes, Spain
| | - Marta E Alarcón-Riquelme
- GENYO, Centre for Genomics and Oncological Research. Pfizer, University of Granada, Andalusian Regional Government, Avda Ilustración 114, PTS Granada 18016, Spain; Institute for Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Concepción Marañón
- GENYO, Centre for Genomics and Oncological Research. Pfizer, University of Granada, Andalusian Regional Government, Avda Ilustración 114, PTS Granada 18016, Spain.
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6
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Ding X, Li Z, Lin G, Li W, Xue L. Toll-7 promotes tumour growth and invasion in Drosophila. Cell Prolif 2022; 55:e13188. [PMID: 35050535 PMCID: PMC8828261 DOI: 10.1111/cpr.13188] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Revised: 12/30/2021] [Accepted: 01/02/2022] [Indexed: 12/25/2022] Open
Abstract
Objectives Drosophila melanogaster has become an excellent model organism to explore the genetic mechanisms underlying tumour progression. Here, by using well‐established Drosophila tumour models, we identified Toll‐7 as a novel regulator of tumour growth and invasion. Materials and methods Transgenic flies and genetic epistasis analysis were used. All flies were raised on a standard cornmeal and agar medium at 25°C unless otherwise indicated. Immunostaining and RT‐qPCR were performed by standard procedures. Images were taken by OLYMPUS BX51 microscope and Zeiss LSM 880 confocal microscope. Adobe Photoshop 2020 and Zeiss Zen were used to analyse the images. All results were presented in Scatter plots or Column bar graphs created by GraphPad Prism 8.0. Results Loss of Toll‐7 suppresses RasV12/lgl−/−‐induced tumour growth and invasion, as well as cell polarity disruption‐induced invasive cell migration, whereas expression of a constitutively active allele of Toll‐7 is sufficient to promote tumorous growth and cell migration. In addition, the Egr‐JNK signalling is necessary and sufficient for Toll‐7‐induced invasive cell migration. Mechanistically, Toll‐7 facilitates the endocytosis of Egr, which is known to activate JNK in the early endosomes. Moreover, Toll‐7 activates the EGFR‐Ras signalling, which cooperates with the Egr‐JNK signalling to promote Yki‐mediated cell proliferation and tissue overgrowth. Finally, Toll‐7 is necessary and sufficient for the proper maintenance of EGFR protein level. Conclusions Our findings characterized Toll‐7 as a proto‐oncogene that promotes tumour growth and invasion in Drosophila, which shed light on the pro‐tumour function of mammalian Toll‐like receptors (TLRs).
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Affiliation(s)
- Xiang Ding
- Institute of Intervention Vessel, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China
| | - Zhuojie Li
- Institute of Intervention Vessel, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China
| | - Gufa Lin
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Orthopaedic Department of Tongji Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Wenzhe Li
- Institute of Intervention Vessel, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China
| | - Lei Xue
- Institute of Intervention Vessel, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China.,Zhuhai Precision Medical Center, Zhuhai People's Hospital, Zhuhai Hospital Affiliated with Jinan University, Zhuhai, China
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7
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Chen CY, Hung YF, Tsai CY, Shih YC, Chou TF, Lai MZ, Wang TF, Hsueh YP. Transcriptomic Analysis and C-Terminal Epitope Tagging Reveal Differential Processing and Signaling of Endogenous TLR3 and TLR7. Front Immunol 2021; 12:686060. [PMID: 34211474 PMCID: PMC8240634 DOI: 10.3389/fimmu.2021.686060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 06/01/2021] [Indexed: 01/02/2023] Open
Abstract
Toll-like receptor (TLR) signaling is critical for defense against pathogenic infection, as well as for modulating tissue development. Activation of different TLRs triggers common inflammatory responses such as cytokine induction. Here, we reveal differential impacts of TLR3 and TLR7 signaling on transcriptomic profiles in bone marrow-derived macrophages (BMDMs). Apart from self-regulation, TLR3, but not TLR7, induced expression of other TLRs, suggesting that TLR3 activation globally enhances innate immunity. Moreover, we observed diverse influences of TLR3 and TLR7 signaling on genes involved in methylation, caspase and autophagy pathways. We compared endogenous TLR3 and TLR7 by using CRISPR/Cas9 technology to knock in a dual Myc-HA tag at the 3’ ends of mouse Tlr3 and Tlr7. Using anti-HA antibodies to detect endogenous tagged TLR3 and TLR7, we found that both TLRs display differential tissue expression and posttranslational modifications. C-terminal tagging did not impair TLR3 activity. However, it disrupted the interaction between TLR7 and myeloid differentiation primary response 88 (MYD88), the Tir domain-containing adaptor of TLR7, which blocked its downstream signaling necessary to trigger cytokine and chemokine expression. Our study demonstrates different properties for TLR3 and TLR7, and also provides useful mouse models for further investigation of these two RNA-sensing TLRs.
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Affiliation(s)
- Chiung-Ya Chen
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Yun-Fen Hung
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Ching-Yen Tsai
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Yi-Chun Shih
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Ting-Fang Chou
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Ming-Zong Lai
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Ting-Fang Wang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Yi-Ping Hsueh
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
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8
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Pang W, Hu F. Cellular and physiological functions of C9ORF72 and implications for ALS/FTD. J Neurochem 2020; 157:334-350. [PMID: 33259633 DOI: 10.1111/jnc.15255] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 10/27/2020] [Accepted: 11/26/2020] [Indexed: 12/12/2022]
Abstract
The hexanucleotide repeat expansion (HRE) in the C9ORF72 gene is the main cause of two tightly linked neurodegenerative diseases, amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). HRE leads to not only a gain of toxicity from RNA repeats and dipeptide repeats but also reduced levels of C9ORF72 protein. However, the cellular and physiological functions of C9ORF72 were unknown until recently. Through proteomic analysis, Smith-Magenis chromosome regions 8 (SMCR8) and WD repeat-containing protein (WDR41) were identified as binding partners of C9ORF72. These three proteins have been shown to form a tight complex, but the exact functions of this complex remain to be characterized. Both C9ORF72 and SMCR8 contain a DENN domain, which has been shown to regulate the activities of small GTPases. The C9ORF72 complex has been implicated in many cellular processes, including vesicle trafficking, lysosome homeostasis, mTORC1 signaling , and autophagy. C9ORF72 deficiency in mice results in exaggerated inflammatory responses and human patients with C9ORF72 mutations have neuroinflammation phenotype. Recent studies indicate that C9ORF72 regulates trafficking and lysosomal degradation of inflammatory mediators, including toll-like receptors (TLRs) and STING, to affect inflammatory outputs. Further exploration of cellular and physiological functions of C9ORF72 will help dissect the pathological mechanism of ALS/FTD caused by C9ORF72 mutations.
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Affiliation(s)
- Weilun Pang
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Fenghua Hu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
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9
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Åsberg SE, Mediaas SD, Marstad A, Ryan L, Louet C, Sporsheim B, Beckwith KS, Underhill DM, Gidon A, Flo TH. Frontline Science: Antibiotic treatment routes Mycobacterium avium to phagolysosomes without triggering proinflammatory cytokine production in human Mϕs. J Leukoc Biol 2020; 109:23-33. [PMID: 32531827 DOI: 10.1002/jlb.4hi0420-306r] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 04/18/2020] [Accepted: 05/19/2020] [Indexed: 12/13/2022] Open
Abstract
Mycobacterium avium (Mav) causes chronic infections in immunocompromised patients that require long-term antibiotic treatment. We have previously shown that Mav takes residence in host Mϕs and establishes a compartment (MavC) in which it is hidden from host defenses. Failure to establish the MavC traps Mav in Lamp1+ phagolysosomes where growth is prevented, and inflammatory signaling activated through TLRs 7/8. To elucidate how antibiotic treatment affects mycobacterial trafficking and host defenses, we infected human primary Mϕs with Mav for 4 days prior to treatment with a macrolide, aminoglycoside, and ethambutol. We show that Mav is killed and the MavC fuses with Lamp1+ lysosomes following antibiotic treatment. However, this does not result in nuclear translocation of NF-κB or production of inflammatory cytokines, suggesting different Lamp1+ lysosomal compartments can form that differ in their innate signaling capabilities. Thus, we show that upon antibiotic treatment of a chronic infection, Mav is quietly disposed of by Mϕs.
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Affiliation(s)
- Signe Elisabeth Åsberg
- Centre of Molecular Inflammation Research, Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Sindre Dahl Mediaas
- Centre of Molecular Inflammation Research, Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Anne Marstad
- Centre of Molecular Inflammation Research, Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Liv Ryan
- Centre of Molecular Inflammation Research, Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Claire Louet
- Centre of Molecular Inflammation Research, Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Bjørnar Sporsheim
- Centre of Molecular Inflammation Research, Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Kai Sandvold Beckwith
- Centre of Molecular Inflammation Research, Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - David Michael Underhill
- Centre of Molecular Inflammation Research, Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology (NTNU), Trondheim, Norway.,Research Division of Immunology, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Alexandre Gidon
- Centre of Molecular Inflammation Research, Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Trude Helen Flo
- Centre of Molecular Inflammation Research, Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
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