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Saleki K, Alijanizadeh P, Javanmehr N, Rezaei N. The role of Toll-like receptors in neuropsychiatric disorders: Immunopathology, treatment, and management. Med Res Rev 2024; 44:1267-1325. [PMID: 38226452 DOI: 10.1002/med.22012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 10/20/2023] [Accepted: 12/20/2023] [Indexed: 01/17/2024]
Abstract
Neuropsychiatric disorders denote a broad range of illnesses involving neurology and psychiatry. These disorders include depressive disorders, anxiety, schizophrenia, bipolar disorder, attention deficit hyperactivity disorder, autism spectrum disorders, headaches, and epilepsy. In addition to their main neuropathology that lies in the central nervous system (CNS), lately, studies have highlighted the role of immunity and neuroinflammation in neuropsychiatric disorders. Toll-like receptors (TLRs) are innate receptors that act as a bridge between the innate and adaptive immune systems via adaptor proteins (e.g., MYD88) and downstream elements; TLRs are classified into 13 families that are involved in normal function and illnesses of the CNS. TLRs expression affects the course of neuropsychiatric disorders, and is influenced during their pharmacotherapy; For example, the expression of multiple TLRs is normalized during the major depressive disorder pharmacotherapy. Here, the role of TLRs in neuroimmunology, treatment, and management of neuropsychiatric disorders is discussed. We recommend longitudinal studies to comparatively assess the cell-type-specific expression of TLRs during treatment, illness progression, and remission. Also, further research should explore molecular insights into TLRs regulation and related pathways.
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Affiliation(s)
- Kiarash Saleki
- Student Research Committee, Babol University of Medical Sciences, Babol, Iran
- USERN Office, Babol University of Medical Sciences, Babol, Iran
- Department of e-Learning, Virtual School of Medical Education and Management, Shahid Beheshti University of Medical Sciences (SBMU), Tehran, Iran
| | - Parsa Alijanizadeh
- Student Research Committee, Babol University of Medical Sciences, Babol, Iran
- USERN Office, Babol University of Medical Sciences, Babol, Iran
| | - Nima Javanmehr
- Student Research Committee, Babol University of Medical Sciences, Babol, Iran
- USERN Office, Babol University of Medical Sciences, Babol, Iran
| | - Nima Rezaei
- Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran
- Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
- Network of Immunity in Infection, Malignancy and Autoimmunity (NIIMA), Universal Scientific Education and Research Network (USERN), Tehran, Iran
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2
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Toshchakov VY. Peptide-Based Inhibitors of the Induced Signaling Protein Interactions: Current State and Prospects. BIOCHEMISTRY. BIOKHIMIIA 2024; 89:784-798. [PMID: 38880642 DOI: 10.1134/s000629792405002x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 02/29/2024] [Accepted: 03/12/2024] [Indexed: 06/18/2024]
Abstract
Formation of the transient protein complexes in response to activation of cellular receptors is a common mechanism by which cells respond to external stimuli. This article presents the concept of blocking interactions of signaling proteins by the peptide inhibitors, and describes the progress achieved to date in the development of signaling inhibitors that act by blocking the signal-dependent protein interactions.
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Affiliation(s)
- Vladimir Y Toshchakov
- Sirius University of Science and Technology, Sirius Federal Territory, Krasnodar Region, 354340, Russia.
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3
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Gama AR, Miller T, Venkatesan S, Lange JJ, Wu J, Song X, Bradford D, Unruh JR, Halfmann R. Protein supersaturation powers innate immune signaling. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.03.20.533581. [PMID: 36993308 PMCID: PMC10055258 DOI: 10.1101/2023.03.20.533581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
Innate immunity protects us in youth but turns against us as we age. The reason for this tradeoff is unclear. Seeking a thermodynamic basis, we focused on death fold domains (DFDs), whose ordered polymerization has been stoichiometrically linked to innate immune signal amplification. We hypothesized that soluble ensembles of DFDs function as phase change batteries that store energy via supersaturation and subsequently release it through nucleated polymerization. Using imaging and FRET-based cytometry to characterize the phase behaviors of all 109 human DFDs, we found that the hubs of innate immune signaling networks encode large nucleation barriers that are intrinsically insulated from cross-pathway activation. We showed via optogenetics that supersaturation drives signal amplification and that the inflammasome is constitutively supersaturated in vivo. Our findings reveal that the soluble "inactive" states of adaptor DFDs function as essential, yet impermanent, kinetic barriers to inflammatory cell death, suggesting a thermodynamic driving force for aging.
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Affiliation(s)
| | - Tayla Miller
- Stowers Institute for Medical Research, Kansas City, MO
| | | | | | - Jianzheng Wu
- Stowers Institute for Medical Research, Kansas City, MO
| | - Xiaoqing Song
- Stowers Institute for Medical Research, Kansas City, MO
| | - Dan Bradford
- Stowers Institute for Medical Research, Kansas City, MO
| | - Jay R Unruh
- Stowers Institute for Medical Research, Kansas City, MO
| | - Randal Halfmann
- Stowers Institute for Medical Research, Kansas City, MO
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, USA
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4
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Ali M, Kumari T, Gupta A, Akhtar S, Verma RD, Ghosh JK. Identification of a 10-mer peptide from the death domain of MyD88 which attenuates inflammation and insulin resistance and improves glucose metabolism. Biochem J 2024; 481:191-218. [PMID: 38224573 DOI: 10.1042/bcj20230369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 01/12/2024] [Accepted: 01/15/2024] [Indexed: 01/17/2024]
Abstract
Insulin resistance (IR) is the key pathophysiological cause of type 2 diabetes, and inflammation has been implicated in it. The death domain (DD) of the adaptor protein, MyD88 plays a crucial role in the transduction of TLR4-associated inflammatory signal. Herein, we have identified a 10-residue peptide (M10), from the DD of MyD88 which seems to be involved in Myddosome formation. We hypothesized that M10 could inhibit MyD88-dependent TLR4-signaling and might have effects on inflammation-associated IR. Intriguingly, 10-mer M10 showed oligomeric nature and reversible self-assembly property indicating the peptide's ability to recognize its own amino acid sequence. M10 inhibited LPS-induced nuclear translocation of NF-κB in L6 myotubes and also reduced LPS-induced IL-6 and TNF-α production in peritoneal macrophages of BALB/c mice. Remarkably, M10 inhibited IL-6 and TNF-α secretion in diabetic, db/db mice. Notably, M10 abrogated IR in insulin-resistant L6 myotubes, which was associated with an increase in glucose uptake and a decrease in Ser307-phosphorylation of IRS1, TNF-α-induced JNK activation and nuclear translocation of NF-κB in these cells. Alternate day dosing with M10 (10 and 20 mg/kg) for 30 days in db/db mice significantly lowered blood glucose and improved glucose intolerance after loading, 3.0 g/kg glucose orally. Furthermore, M10 increased insulin and adiponectin secretion in db/db mice. M10-induced glucose uptake in L6 myotubes involved the activation of PI3K/AKT/GLUT4 pathways. A scrambled M10-analog was mostly inactive. Overall, the results show the identification of a 10-mer peptide from the DD of MyD88 with anti-inflammatory and anti-diabetic properties, suggesting that targeting of TLR4-inflammatory pathway, could lead to the discovery of molecules against IR and diabetes.
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Affiliation(s)
- Mehmood Ali
- Biochemistry and Structural Biology Division, CSIR-Central Drug Research Institute, Lucknow 226 031 India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002 India
| | - Tripti Kumari
- Biochemistry and Structural Biology Division, CSIR-Central Drug Research Institute, Lucknow 226 031 India
| | - Arvind Gupta
- Biochemistry and Structural Biology Division, CSIR-Central Drug Research Institute, Lucknow 226 031 India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002 India
| | - Sariyah Akhtar
- Biochemistry and Structural Biology Division, CSIR-Central Drug Research Institute, Lucknow 226 031 India
| | - Rahul Dev Verma
- Biochemistry and Structural Biology Division, CSIR-Central Drug Research Institute, Lucknow 226 031 India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002 India
| | - Jimut Kanti Ghosh
- Biochemistry and Structural Biology Division, CSIR-Central Drug Research Institute, Lucknow 226 031 India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002 India
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5
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Zhong Y, Zhong X, Qiao L, Wu H, Liu C, Zhang T. Zα domain proteins mediate the immune response. Front Immunol 2023; 14:1241694. [PMID: 37771585 PMCID: PMC10523160 DOI: 10.3389/fimmu.2023.1241694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Accepted: 08/23/2023] [Indexed: 09/30/2023] Open
Abstract
The Zα domain has a compact α/β architecture containing a three-helix bundle flanked on one side by a twisted antiparallel β sheet. This domain displays a specific affinity for double-stranded nucleic acids that adopt a left-handed helical conformation. Currently, only three Zα-domain proteins have been identified in eukaryotes, specifically ADAR1, ZBP1, and PKZ. ADAR1 is a double-stranded RNA (dsRNA) binding protein that catalyzes the conversion of adenosine residues to inosine, resulting in changes in RNA structure, function, and expression. In addition to its editing function, ADAR1 has been shown to play a role in antiviral defense, gene regulation, and cellular differentiation. Dysregulation of ADAR1 expression and activity has been associated with various disease states, including cancer, autoimmune disorders, and neurological disorders. As a sensing molecule, ZBP1 exhibits the ability to recognize nucleic acids with a left-handed conformation. ZBP1 harbors a RIP homotypic interaction motif (RHIM), composed of a highly charged surface region and a leucine-rich hydrophobic core, enabling the formation of homotypic interactions between proteins with similar structure. Upon activation, ZBP1 initiates a downstream signaling cascade leading to programmed cell death, a process mediated by RIPK3 via the RHIM motif. PKZ was identified in fish, and contains two Zα domains at the N-terminus. PKZ is essential for normal growth and development and may contribute to the regulation of immune system function in fish. Interestingly, some pathogenic microorganisms also encode Zα domain proteins, such as, Vaccinia virus and Cyprinid Herpesvirus. Zα domain proteins derived from pathogenic microorganisms have been demonstrated to be pivotal contributors in impeding the host immune response and promoting virus replication and spread. This review focuses on the mammalian Zα domain proteins: ADAR1 and ZBP1, and thoroughly elucidates their functions in the immune response.
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Affiliation(s)
- Yuhan Zhong
- Laboratory of Liver Transplantation, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
| | - Xiao Zhong
- Laboratory of Liver Transplantation, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
- Institute of Life Sciences, Chongqing Medical University, Chongqing, China
| | - Liangjun Qiao
- Institute of Life Sciences, Chongqing Medical University, Chongqing, China
| | - Hong Wu
- Laboratory of Liver Transplantation, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
| | - Chang Liu
- Division of Liver, Department of General Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Ting Zhang
- Laboratory of Liver Transplantation, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
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6
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Wang X, Li X, Yu G, Zhang L, Zhang C, Wang Y, Liao F, Wen Y, Yin H, Liu X, Wei Y, Li Z, Deng Z, Zhang H. Structural insights into mechanisms of Argonaute protein-associated NADase activation in bacterial immunity. Cell Res 2023; 33:699-711. [PMID: 37311833 PMCID: PMC10474274 DOI: 10.1038/s41422-023-00839-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Accepted: 05/29/2023] [Indexed: 06/15/2023] Open
Abstract
Nicotinamide adenine dinucleotide (NAD+) is a central metabolite in cellular processes. Depletion of NAD+ has been demonstrated to be a prevalent theme in both prokaryotic and eukaryotic immune responses. Short prokaryotic Argonaute proteins (Agos) are associated with NADase domain-containing proteins (TIR-APAZ or SIR2-APAZ) encoded in the same operon. They confer immunity against mobile genetic elements, such as bacteriophages and plasmids, by inducing NAD+ depletion upon recognition of target nucleic acids. However, the molecular mechanisms underlying the activation of such prokaryotic NADase/Ago immune systems remain unknown. Here, we report multiple cryo-EM structures of NADase/Ago complexes from two distinct systems (TIR-APAZ/Ago and SIR2-APAZ/Ago). Target DNA binding triggers tetramerization of the TIR-APAZ/Ago complex by a cooperative self-assembly mechanism, while the heterodimeric SIR2-APAZ/Ago complex does not assemble into higher-order oligomers upon target DNA binding. However, the NADase activities of these two systems are unleashed via a similar closed-to-open transition of the catalytic pocket, albeit by different mechanisms. Furthermore, a functionally conserved sensor loop is employed to inspect the guide RNA-target DNA base pairing and facilitate the conformational rearrangement of Ago proteins required for the activation of these two systems. Overall, our study reveals the mechanistic diversity and similarity of Ago protein-associated NADase systems in prokaryotic immune response.
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Affiliation(s)
- Xiaoshen Wang
- National key laboratory of blood science, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Haihe Laboratory of Cell Ecosystem, Tianjin Institute of Immunology, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Xuzichao Li
- National key laboratory of blood science, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Haihe Laboratory of Cell Ecosystem, Tianjin Institute of Immunology, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Guimei Yu
- National key laboratory of blood science, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Haihe Laboratory of Cell Ecosystem, Tianjin Institute of Immunology, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Lingling Zhang
- National key laboratory of blood science, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Haihe Laboratory of Cell Ecosystem, Tianjin Institute of Immunology, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Chendi Zhang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, China
| | - Yong Wang
- Center for Antiviral Research, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Fumeng Liao
- National key laboratory of blood science, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Haihe Laboratory of Cell Ecosystem, Tianjin Institute of Immunology, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Yanan Wen
- National key laboratory of blood science, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Haihe Laboratory of Cell Ecosystem, Tianjin Institute of Immunology, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Hang Yin
- Department of Pharmacology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Xiang Liu
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, College of Life Sciences, Nankai University, Tianjin, China
| | - Yong Wei
- The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences, Hangzhou, Zhejiang, China
| | - Zhuang Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, China.
| | - Zengqin Deng
- Center for Antiviral Research, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, China.
- Hubei Jiangxia Laboratory, Wuhan, Hubei, China.
| | - Heng Zhang
- National key laboratory of blood science, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Haihe Laboratory of Cell Ecosystem, Tianjin Institute of Immunology, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China.
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7
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Maruta N, Sorbello M, Lim BYJ, McGuinness HY, Shi Y, Ve T, Kobe B. TIR domain-associated nucleotides with functions in plant immunity and beyond. CURRENT OPINION IN PLANT BIOLOGY 2023; 73:102364. [PMID: 37086529 DOI: 10.1016/j.pbi.2023.102364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 02/19/2023] [Accepted: 03/09/2023] [Indexed: 05/03/2023]
Abstract
TIR (Toll/interlukin-1 receptor) domains are found in archaea, bacteria and eukaryotes, featured in proteins generally associated with immune functions. In plants, they are found in a large group of NLRs (nucleotide-binding leucine-rich repeat receptors), NLR-like proteins and TIR-only proteins. They are also present in effector proteins from phytopathogenic bacteria that are associated with suppression of host immunity. TIR domains from plants and bacteria are enzymes that cleave NAD+ (nicotinamide adenine dinucleotide, oxidized form) and other nucleotides. In dicot plants, TIR-derived signalling molecules activate downstream immune signalling proteins, the EDS1 (enhanced disease susceptibility 1) family proteins, and in turn helper NLRs. Recent work has brought major advances in understanding how TIR domains work, how they produce signalling molecules and how these products signal.
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Affiliation(s)
- Natsumi Maruta
- The University of Queensland, School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, Brisbane, QLD 4072, Australia
| | - Mitchell Sorbello
- The University of Queensland, School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, Brisbane, QLD 4072, Australia
| | - Bryan Y J Lim
- The University of Queensland, School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, Brisbane, QLD 4072, Australia
| | - Helen Y McGuinness
- The University of Queensland, School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, Brisbane, QLD 4072, Australia
| | - Yun Shi
- Institute for Glycomics, Griffith University, Southport, QLD 4222, Australia
| | - Thomas Ve
- Institute for Glycomics, Griffith University, Southport, QLD 4222, Australia
| | - Bostjan Kobe
- The University of Queensland, School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, Brisbane, QLD 4072, Australia.
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8
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Pham CLL, Titaux-Delgado GA, Varghese NR, Polonio P, Wilde KL, Sunde M, Mompeán M. NMR characterization of an assembling RHIM (RIP homotypic interaction motif) amyloid reveals a cryptic region for self-recognition. J Biol Chem 2023; 299:104568. [PMID: 36870681 PMCID: PMC10070927 DOI: 10.1016/j.jbc.2023.104568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/25/2023] [Accepted: 02/27/2023] [Indexed: 03/06/2023] Open
Abstract
The RIP homotypic interaction motif (RHIM) is an essential protein motif in inflammatory signaling and certain cell death pathways. RHIM signaling occurs following the assembly of functional amyloids, and while the structural biology of such higher-order RHIM complexes has started to emerge, the conformations and dynamics of nonassembled RHIMs remain unknown. Here, using solution NMR spectroscopy, we report the characterization of the monomeric form of the RHIM in receptor-interacting protein kinase 3 (RIPK3), a fundamental protein in human immunity. Our results establish that the RHIM of RIPK3 is an intrinsically disordered protein motif, contrary to prediction, and that exchange dynamics between free monomers and amyloid-bound RIPK3 monomers involve a 20-residue stretch outside the RHIM that is not incorporated within the structured cores of the RIPK3 assemblies determined by cryo-EM or solid-state NMR. Thus, our findings expand on the structural characterization of RHIM-containing proteins, specifically highlighting conformational dynamics involved in assembly processes.
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Affiliation(s)
- Chi L L Pham
- School of Medical Sciences, Sydney Nano and Sydney Infectious Diseases, University of Sydney, Sydney, New South Wales, Australia
| | | | - Nikhil R Varghese
- School of Medical Sciences, Sydney Nano and Sydney Infectious Diseases, University of Sydney, Sydney, New South Wales, Australia
| | - Paula Polonio
- "Rocasolano" Institute of Physical Chemistry, Spanish National Research Council, Madrid, Spain
| | - Karyn L Wilde
- National Deuteration Facility Australian Nuclear Science and Technology Organization (ANSTO), Sydney, New South Wales, Australia
| | - Margaret Sunde
- School of Medical Sciences, Sydney Nano and Sydney Infectious Diseases, University of Sydney, Sydney, New South Wales, Australia
| | - Miguel Mompeán
- "Rocasolano" Institute of Physical Chemistry, Spanish National Research Council, Madrid, Spain.
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9
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Sarkar A, Kumari N, Mukherjee P. The curious case of SARM1: Dr. Jekyll and Mr. Hyde in cell death and immunity? FEBS J 2023; 290:340-358. [PMID: 34710262 DOI: 10.1111/febs.16256] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 09/21/2021] [Accepted: 10/27/2021] [Indexed: 02/06/2023]
Abstract
Sterile alpha and toll/interleukin-1 receptor motif-containing protein 1 (SARM1) was first identified as a novel ortholog of Drosophila protein CG7915 and was subsequently placed as the fifth member of the human TIR-containing adaptor protein. SARM1 holds a unique position in this family where, unlike other members, it downregulates NFκB activity in response to immunogenic stimulation, interacts with another member of the family, TRIF, to negatively regulate its function, and it also mediates cell death responses. Over the past decade, SARM1 has emerged as one of the primary mediators of programmed axonal degeneration and this robust regulation of axonal degeneration-especially in models of peripheral neuropathy and traumatic injury-makes it an attractive target for therapeutic intervention. The TIR domain of SARM1 possesses an intrinsic NADase activity resulting in cellular energy deficits within the axons, a striking deviation from its other family members of human TLR adaptors. Interestingly, the TIR NADase activity, as seen in SARM1, is also observed in several prokaryotic TIR-containing proteins where they are involved in immune evasion once within the host. Although the immune function of SARM1 is yet to be conclusively discerned, this closeness in function with the prokaryotic TIR-domain containing proteins, places it at an interesting juncture of evolution raising questions about its origin and function in cell death and immunity. In this review, we discuss how a conserved immune adaptor protein like SARM1 switches to a pro-neurodegenerative function and the evolutionarily significance of the process.
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Affiliation(s)
- Ankita Sarkar
- School of Biotechnology, Presidency University, Kolkata, West Bengal, India
| | - Nripa Kumari
- School of Biotechnology, Presidency University, Kolkata, West Bengal, India
| | - Piyali Mukherjee
- School of Biotechnology, Presidency University, Kolkata, West Bengal, India
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10
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Riesgo A, Santodomingo N, Koutsouveli V, Kumala L, Leger MM, Leys SP, Funch P. Molecular machineries of ciliogenesis, cell survival, and vasculogenesis are differentially expressed during regeneration in explants of the demosponge Halichondria panicea. BMC Genomics 2022; 23:858. [PMID: 36581804 PMCID: PMC9798719 DOI: 10.1186/s12864-022-09035-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 11/21/2022] [Indexed: 12/30/2022] Open
Abstract
Sponges are interesting animal models for regeneration studies, since even from dissociated cells, they are able to regenerate completely. In particular, explants are model systems that can be applied to many sponge species, since small fragments of sponges can regenerate all elements of the adult, including the oscula and the ability to pump water. The morphological aspects of regeneration in sponges are relatively well known, but the molecular machinery is only now starting to be elucidated for some sponge species. Here, we have used an explant system of the demosponge Halichondria panicea to understand the molecular machinery deployed during regeneration of the aquiferous system. We sequenced the transcriptomes of four replicates of the 5-day explant without an osculum (NOE), four replicates of the 17-18-day explant with a single osculum and pumping activity (PE) and also four replicates of field-collected individuals with regular pumping activity (PA), and performed differential gene expression analysis. We also described the morphology of NOE and PE samples using light and electron microscopy. Our results showed a highly disorganised mesohyl and disarranged aquiferous system in NOE that is coupled with upregulated pathways of ciliogenesis, organisation of the ECM, and cell proliferation and survival. Once the osculum is formed, genes involved in "response to stimulus in other organisms" were upregulated. Interestingly, the main molecular machinery of vasculogenesis described in vertebrates was activated during the regeneration of the aquiferous system. Notably, vasculogenesis markers were upregulated when the tissue was disorganised and about to start forming canals (NOE) and angiogenic stimulators and ECM remodelling machineries were differentially expressed once the aquiferous system was in place (PE and PA). Our results are fundamental to better understanding the molecular mechanisms involved in the formation of the aquiferous system in sponges, and its similarities with the early onset of blood-vessel formation in animal evolution.
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Affiliation(s)
- Ana Riesgo
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (CSIC), Calle José Gutiérrez Abascal 2, 28006, Madrid, Spain.
- Department of Life Sciences, Natural History Museum, Cromwell Road, London, SW5 7BD, UK.
| | - Nadia Santodomingo
- Department of Life Sciences, Natural History Museum, Cromwell Road, London, SW5 7BD, UK
- Department of Earth Sciences, Oxford University, South Parks Road, Oxford, OX1 3AN, UK
| | - Vasiliki Koutsouveli
- Marine Symbioses Research Unit, GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker Weg 20, D-24105, Kiel, Germany
| | - Lars Kumala
- Nordcee, Department of Biology, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
- Marine Biological Research Center, University of Southern Denmark, Hindsholmvej 11, 5300, Kerteminde, Denmark
| | - Michelle M Leger
- Institute of Evolutionary Biology (CSIC-UPF), Paseo Marítimo de la Barceloneta 37-49, 08003, Barcelona, Spain
| | - Sally P Leys
- Department of Biological Sciences, University of Alberta, 11455 Saskatchewan Drive, Edmonton, Alberta, T6G 2R3, Canada
| | - Peter Funch
- Department of Biology, Aarhus University, Ny Munkegade, 114-116, Aarhus C, Denmark
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11
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The role of RHIM in necroptosis. Biochem Soc Trans 2022; 50:1197-1205. [PMID: 36040212 PMCID: PMC9444067 DOI: 10.1042/bst20220535] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 08/05/2022] [Accepted: 08/09/2022] [Indexed: 11/17/2022]
Abstract
The RIP homotypic interaction motif (RHIM) is a conserved protein domain that is approximately 18–22 amino acids in length. In humans, four proteins carrying RHIM domains have been identified: receptor-interacting serine/threonine protein kinase (RIPK) 1, RIPK3, Z-DNA-binding protein 1 (ZBP1), and TIR domain-containing adapter-inducing IFN-β (TRIF), which are all major players in necroptosis, a distinct form of regulated cell death. Necroptosis is mostly presumed to be a fail-safe form of cell death, occurring in cells in which apoptosis is compromised. Upon activation, RIPK1, ZBP1, and TRIF each hetero-oligomerize with RIPK3 and induce the assembly of an amyloid-like structure of RIPK3 homo-oligomers. These act as docking stations for the recruitment of the pseudokinase mixed-lineage kinase domain like (MLKL), the pore-forming executioner of necroptosis. As RHIM domain interactions are a vital component of the signaling cascade and can also be involved in apoptosis and pyroptosis activation, it is unsurprising that viral and bacterial pathogens have developed means of disrupting RHIM-mediated signaling to ensure survival. Moreover, as these mechanisms play an essential part of regulated cell death signaling, they have received much attention in recent years. Herein, we present the latest insights into the supramolecular structure of interacting RHIM proteins and their distinct signaling cascades in inflammation and infection. Their uncovering will ultimately contribute to the development of new therapeutic strategies in the regulation of lytic cell death.
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12
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Lee E, Redzic JS, Nemkov T, Saviola AJ, Dzieciatkowska M, Hansen KC, D’Alessandro A, Dinarello C, Eisenmesser EZ. Human and Bacterial Toll-Interleukin Receptor Domains Exhibit Distinct Dynamic Features and Functions. Molecules 2022; 27:4494. [PMID: 35889366 PMCID: PMC9318647 DOI: 10.3390/molecules27144494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/08/2022] [Accepted: 07/11/2022] [Indexed: 02/04/2023] Open
Abstract
Toll-interleukin receptor (TIR) domains have emerged as critical players involved in innate immune signaling in humans but are also expressed as potential virulence factors within multiple pathogenic bacteria. However, there has been a shortage of structural studies aimed at elucidating atomic resolution details with respect to their interactions, potentially owing to their dynamic nature. Here, we used a combination of biophysical and biochemical studies to reveal the dynamic behavior and functional interactions of a panel of both bacterial TIR-containing proteins and mammalian receptor TIR domains. Regarding dynamics, all three bacterial TIR domains studied here exhibited an inherent exchange that led to severe resonance line-broadening, revealing their intrinsic dynamic nature on the intermediate NMR timescale. In contrast, the three mammalian TIR domains studied here exhibited a range in terms of their dynamic exchange that spans multiple timescales. Functionally, only the bacterial TIR domains were catalytic towards the cleavage of NAD+, despite the conservation of the catalytic nucleophile on human TIR domains. Our development of NMR-based catalytic assays allowed us to further identify differences in product formation for gram-positive versus gram-negative bacterial TIR domains. Differences in oligomeric interactions were also revealed, whereby bacterial TIR domains self-associated solely through their attached coil-coil domains, in contrast to the mammalian TIR domains that formed homodimers and heterodimers through reactive cysteines. Finally, we provide the first atomic-resolution studies of a bacterial coil-coil domain and provide the first atomic model of the TIR domain from a human anti-inflammatory IL-1R8 protein that undergoes a slow inherent exchange.
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Affiliation(s)
- Eunjeong Lee
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Anschutz Medical Campus, 12801 E 17th Ave, Aurora, CO 80045, USA; (E.L.); (J.S.R.); (T.N.); (A.J.S.); (M.D.); (K.C.H.); (A.D.)
| | - Jasmina S. Redzic
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Anschutz Medical Campus, 12801 E 17th Ave, Aurora, CO 80045, USA; (E.L.); (J.S.R.); (T.N.); (A.J.S.); (M.D.); (K.C.H.); (A.D.)
| | - Travis Nemkov
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Anschutz Medical Campus, 12801 E 17th Ave, Aurora, CO 80045, USA; (E.L.); (J.S.R.); (T.N.); (A.J.S.); (M.D.); (K.C.H.); (A.D.)
| | - Anthony J. Saviola
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Anschutz Medical Campus, 12801 E 17th Ave, Aurora, CO 80045, USA; (E.L.); (J.S.R.); (T.N.); (A.J.S.); (M.D.); (K.C.H.); (A.D.)
| | - Monika Dzieciatkowska
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Anschutz Medical Campus, 12801 E 17th Ave, Aurora, CO 80045, USA; (E.L.); (J.S.R.); (T.N.); (A.J.S.); (M.D.); (K.C.H.); (A.D.)
| | - Kirk C. Hansen
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Anschutz Medical Campus, 12801 E 17th Ave, Aurora, CO 80045, USA; (E.L.); (J.S.R.); (T.N.); (A.J.S.); (M.D.); (K.C.H.); (A.D.)
| | - Angelo D’Alessandro
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Anschutz Medical Campus, 12801 E 17th Ave, Aurora, CO 80045, USA; (E.L.); (J.S.R.); (T.N.); (A.J.S.); (M.D.); (K.C.H.); (A.D.)
| | - Charles Dinarello
- Department of Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, 12801 E 17th Ave, Aurora, CO 80045, USA;
- Department of Internal Medicine, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Elan Z. Eisenmesser
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Anschutz Medical Campus, 12801 E 17th Ave, Aurora, CO 80045, USA; (E.L.); (J.S.R.); (T.N.); (A.J.S.); (M.D.); (K.C.H.); (A.D.)
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13
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Essuman K, Milbrandt J, Dangl JL, Nishimura MT. Shared TIR enzymatic functions regulate cell death and immunity across the tree of life. Science 2022; 377:eabo0001. [DOI: 10.1126/science.abo0001] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In the 20th century, researchers studying animal and plant signaling pathways discovered a protein domain shared across diverse innate immune systems: the Toll/Interleukin-1/Resistance-gene (TIR) domain. The TIR domain is found in several protein architectures and was defined as an adaptor mediating protein-protein interactions in animal innate immunity and developmental signaling pathways. However, studies of nerve degeneration in animals, and subsequent breakthroughs in plant, bacterial and archaeal systems, revealed that TIR domains possess enzymatic activities. We provide a synthesis of TIR functions and the role of various related TIR enzymatic products in evolutionarily diverse immune systems. These studies may ultimately guide interventions that would span the tree of life, from treating human neurodegenerative disorders and bacterial infections, to preventing plant diseases.
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Affiliation(s)
- Kow Essuman
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Jeffrey Milbrandt
- Department of Genetics, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
- Needleman Center for Neurometabolism and Axonal Therapeutics, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
- McDonnell Genome Institute, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - Jeffery L. Dangl
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Howard Hughes Medical Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Marc T. Nishimura
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
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14
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Cao B, Chen Y, Cui J, Sun Y, Xu T. Zw10 negatively regulates the MyD88-mediated NF-κB signaling through autophagy in teleost fish. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2022; 132:104401. [PMID: 35339534 DOI: 10.1016/j.dci.2022.104401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 03/19/2022] [Accepted: 03/19/2022] [Indexed: 06/14/2023]
Abstract
MyD88 is a typical street protein of the TLRs signaling pathway and is a central player in innate immune signaling, which can regulate the NF-κB signaling pathway and promote downstream inflammatory factors. However, studies on the molecular mechanisms of the MyD88-mediated NF-κB signaling pathway in teleosts have been poorly reported. In this study, we report that Zw10 targets MyD88 to inhibit NF-κB activation. Zw10 inhibits cell proliferation and MyD88-mediated innate immunity in fish. Zw10 interacts with MyD88, and its Δ2 domain is very critical for MyD88 degradation. In addition, we found that Zw10 degrade MyD88 by autophagy, thereby negatively regulating the MyD88-mediated NF-κB signaling pathway. This study not only enriches the research on the innate immunity of teleost fish, but also provides insights for the regulating mechanism for mammals.
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Affiliation(s)
- Baolan Cao
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Ya Chen
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Junxia Cui
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Yuena Sun
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, China; National Pathogen Collection Center for Aquatic Animals, Shanghai Ocean University, China.
| | - Tianjun Xu
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China; Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, China; National Pathogen Collection Center for Aquatic Animals, Shanghai Ocean University, China.
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15
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Rodriguez Gama A, Miller T, Lange JJ, Unruh JR, Halfmann R. A nucleation barrier spring-loads the CBM signalosome for binary activation. eLife 2022; 11:79826. [PMID: 35727133 PMCID: PMC9342958 DOI: 10.7554/elife.79826] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 06/20/2022] [Indexed: 11/26/2022] Open
Abstract
Immune cells activate in binary, switch-like fashion via large protein assemblies known as signalosomes, but the molecular mechanism of the switch is not yet understood. Here, we employed an in-cell biophysical approach to dissect the assembly mechanism of the CARD-BCL10-MALT1 (CBM) signalosome, which governs nuclear transcription factor-κB activation in both innate and adaptive immunity. We found that the switch consists of a sequence-encoded and deeply conserved nucleation barrier to ordered polymerization by the adaptor protein BCL10. The particular structure of the BCL10 polymers did not matter for activity. Using optogenetic tools and single-cell transcriptional reporters, we discovered that endogenous BCL10 is functionally supersaturated even in unstimulated human cells, and this results in a predetermined response to stimulation upon nucleation by activated CARD multimers. Our findings may inform on the progressive nature of age-associated inflammation, and suggest that signalosome structure has evolved via selection for kinetic rather than equilibrium properties of the proteins. The innate immune system is the body’s first line of defence against pathogens. Although innate immune cells do not recognize specific disease-causing agents, they can detect extremely low levels of harmful organisms or substances. In response, they activate signals that lead to inflammation, which tells other cells that there is an infection. Innate immune cells are turned on in a switch-like fashion, becoming active very quickly after interacting with a pathogen. This is due to the action of signalosomes, large complexes made up of several proteins that clump together to form long chains that activate the cell. But how do these large protein complexes assemble quick enough to create the switch-like activation observed in innate immune cells? To answer this question, Rodríguez Gama et al. focused on the CBM signalosome, which is involved in triggering inflammation through the activation of a protein called NF-kB. First, Rodríguez Gama et al. used genetic tools to determine that activating the CBM signalosome drives a switch-like activation of NF-kB in cells. This means that individual cells in a population either become fully activated or not at all in response to minute amounts of harmful substances. Once they had established this, Rodríguez Gama et al. wanted to know which protein in the CBM signalosome was responsible for the switch. They found that one of the proteins in the signalosome, called BCL10, has a ‘nucleation barrier’ encoded in its sequence. This means that it is very hard for BCL10 to start clumping together, but once it does, the clumps grow on their own. The nucleation barrier describes exactly how hard it is for these clumps to get started, and is determined by how disorganized the protein is. When a pathogen ‘stimulates’ an immune cell, a tiny template is formed that lowers the nucleation barrier so that BCL10 can then aggregate itself together, leading to the switch-like behaviour observed. The nucleation barrier allows there to be more than enough BCL10 present in the cell at all times – ready to clump together at a moment’s notice – and this permits the cell to detect very low levels of a pathogen. Rodríguez Gama et al. then tested whether BCL10 from other animals also has a nucleation barrier. They found that this feature is conserved from cnidarians, such as corals or jellyfish, to mammals, including humans. This suggests that the use of nucleation barriers to regulate innate immune signalling has existed for a long time throughout evolution. The work by Rodríguez Gama et al. broadens our understanding of how the innate immune system senses and responds to extremely low levels of pathogens. That BCL10 is always ready to clump together suggests it may be a driving force for chronic and age-associated inflammation. Additionally, the findings of Rodríguez Gama et al. also offer insights into how other signalosomes may become activated, and offer the possibility of new drugs aimed at modifying nucleation barriers.
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Affiliation(s)
| | - Tayla Miller
- Stowers Institute for Medical Research, Kansas City, United States
| | - Jeffrey J Lange
- Stowers Institute for Medical Research, Kansas City, United States
| | - Jay R Unruh
- Stowers Institute for Medical Research, Kansas City, United States
| | - Randal Halfmann
- Stowers Institute for Medical Research, Kansas City, United States
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16
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Nimma S, Gu W, Maruta N, Li Y, Pan M, Saikot FK, Lim BYJ, McGuinness HY, Zaoti ZF, Li S, Desa S, Manik MK, Nanson JD, Kobe B. Structural Evolution of TIR-Domain Signalosomes. Front Immunol 2021; 12:784484. [PMID: 34868065 PMCID: PMC8635717 DOI: 10.3389/fimmu.2021.784484] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 10/25/2021] [Indexed: 01/23/2023] Open
Abstract
TIR (Toll/interleukin-1 receptor/resistance protein) domains are cytoplasmic domains widely found in animals and plants, where they are essential components of the innate immune system. A key feature of TIR-domain function in signaling is weak and transient self-association and association with other TIR domains. An additional new role of TIR domains as catalytic enzymes has been established with the recent discovery of NAD+-nucleosidase activity by several TIR domains, mostly involved in cell-death pathways. Although self-association of TIR domains is necessary in both cases, the functional specificity of TIR domains is related in part to the nature of the TIR : TIR interactions in the respective signalosomes. Here, we review the well-studied TIR domain-containing proteins involved in eukaryotic immunity, focusing on the structures, interactions and their corresponding functional roles. Structurally, the signalosomes fall into two separate groups, the scaffold and enzyme TIR-domain assemblies, both of which feature open-ended complexes with two strands of TIR domains, but differ in the orientation of the two strands. We compare and contrast how TIR domains assemble and signal through distinct scaffolding and enzymatic roles, ultimately leading to distinct cellular innate-immunity and cell-death outcomes.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD, Australia
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17
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DiAntonio A, Milbrandt J, Figley MD. The SARM1 TIR NADase: Mechanistic Similarities to Bacterial Phage Defense and Toxin-Antitoxin Systems. Front Immunol 2021; 12:752898. [PMID: 34630431 PMCID: PMC8494770 DOI: 10.3389/fimmu.2021.752898] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 08/26/2021] [Indexed: 01/19/2023] Open
Abstract
The Toll/interleukin-1 receptor (TIR) domain is the signature signalling motif of innate immunity, with essential roles in innate immune signalling in bacteria, plants, and animals. TIR domains canonically function as scaffolds, with stimulus-dependent multimerization generating binding sites for signalling molecules such as kinases and ligases that activate downstream immune mechanisms. Recent studies have dramatically expanded our understanding of the TIR domain, demonstrating that the primordial function of the TIR domain is to metabolize NAD+. Mammalian SARM1, the central executioner of pathological axon degeneration, is the founding member of the TIR-domain class of NAD+ hydrolases. This unexpected NADase activity of TIR domains is evolutionarily conserved, with archaeal, bacterial, and plant TIR domains all sharing this catalytic function. Moreover, this enzymatic activity is essential for the innate immune function of these proteins. These evolutionary relationships suggest a link between SARM1 and ancient self-defense mechanisms that has only been strengthened by the recent discovery of the SARM1 activation mechanism which, we will argue, is strikingly similar to bacterial toxin-antitoxin systems. In this brief review we will describe the regulation and function of SARM1 in programmed axon self-destruction, and highlight the parallels between the SARM1 axon degeneration pathway and bacterial innate immune mechanisms.
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Affiliation(s)
- Aaron DiAntonio
- Department of Developmental Biology, Washington University School of Medicine in Saint Louis, St. Louis, MO, United States
- Needleman Center for Neurometabolism and Axonal Therapeutics, Washington University School of Medicine in Saint Louis, St. Louis, MO, United States
| | - Jeffrey Milbrandt
- Needleman Center for Neurometabolism and Axonal Therapeutics, Washington University School of Medicine in Saint Louis, St. Louis, MO, United States
- Department of Genetics, Washington University School of Medicine in Saint Louis, St. Louis, MO, United States
| | - Matthew D Figley
- Department of Developmental Biology, Washington University School of Medicine in Saint Louis, St. Louis, MO, United States
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18
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Valenti M, Molina M, Cid VJ. Heterologous Expression and Auto-Activation of Human Pro-Inflammatory Caspase-1 in Saccharomyces cerevisiae and Comparison to Caspase-8. Front Immunol 2021; 12:668602. [PMID: 34335569 PMCID: PMC8317575 DOI: 10.3389/fimmu.2021.668602] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 06/28/2021] [Indexed: 01/15/2023] Open
Abstract
Caspases are a family of cysteine proteases that play an essential role in inflammation, apoptosis, cell death, and development. Here we delve into the effects caused by heterologous expression of human caspase-1 in the yeast Saccharomyces cerevisiae and compare them to those of caspase-8. Overexpression of both caspases in the heterologous model led to their activation and caused mitochondrial hyperpolarization, damage to different organelles, and cell death. All these effects were dependent on their protease activity, and caspase-8 was more aggressive than caspase-1. Growth arrest could be at least partially explained by dysfunction of the actin cytoskeleton as a consequence of the processing of the yeast Bni1 formin, which we identify here as a likely direct substrate of both caspases. Through the modulation of the GAL1 promoter by using different galactose:glucose ratios in the culture medium, we have established a scenario in which caspase-1 is sufficiently expressed to become activated while yeast growth is not impaired. Finally, we used the yeast model to explore the role of death-fold domains (DD) of both caspases in their activity. Peculiarly, the DDs of either caspase showed an opposite involvement in its intrinsic activity, as the deletion of the caspase activation and recruitment domain (CARD) of caspase-1 enhanced its activity, whereas the deletion of the death effector domain (DED) of caspase-8 diminished it. We show that caspase-1 is able to efficiently process its target gasdermin D (GSDMD) when co-expressed in yeast. In sum, we propose that S. cerevisiae provides a manageable tool to explore caspase-1 activity and structure–function relationships.
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Affiliation(s)
- Marta Valenti
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, Instituto Ramón y Cajal de Investigaciones Sanitarias (IRYCIS), Universidad Complutense de Madrid, Madrid, Spain
| | - María Molina
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, Instituto Ramón y Cajal de Investigaciones Sanitarias (IRYCIS), Universidad Complutense de Madrid, Madrid, Spain
| | - Víctor J Cid
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, Instituto Ramón y Cajal de Investigaciones Sanitarias (IRYCIS), Universidad Complutense de Madrid, Madrid, Spain
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19
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Hopkins EL, Gu W, Kobe B, Coleman MP. A Novel NAD Signaling Mechanism in Axon Degeneration and its Relationship to Innate Immunity. Front Mol Biosci 2021; 8:703532. [PMID: 34307460 PMCID: PMC8295901 DOI: 10.3389/fmolb.2021.703532] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/28/2021] [Indexed: 12/21/2022] Open
Abstract
Axon degeneration represents a pathological feature of many neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease where axons die before the neuronal soma, and axonopathies, such as Charcot-Marie-Tooth disease and hereditary spastic paraplegia. Over the last two decades, it has slowly emerged that a central signaling pathway forms the basis of this process in many circumstances. This is an axonal NAD-related signaling mechanism mainly regulated by the two key proteins with opposing roles: the NAD-synthesizing enzyme NMNAT2, and SARM1, a protein with NADase and related activities. The crosstalk between the axon survival factor NMNAT2 and pro-degenerative factor SARM1 has been extensively characterized and plays an essential role in maintaining the axon integrity. This pathway can be activated in necroptosis and in genetic, toxic or metabolic disorders, physical injury and neuroinflammation, all leading to axon pathology. SARM1 is also known to be involved in regulating innate immunity, potentially linking axon degeneration to the response to pathogens and intercellular signaling. Understanding this NAD-related signaling mechanism enhances our understanding of the process of axon degeneration and enables a path to the development of drugs for a wide range of neurodegenerative diseases.
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Affiliation(s)
- Eleanor L. Hopkins
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom
| | - Weixi Gu
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, QLD, Australia
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, QLD, Australia
| | - Michael P. Coleman
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom
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20
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Manes NP, Nita-Lazar A. Molecular Mechanisms of the Toll-Like Receptor, STING, MAVS, Inflammasome, and Interferon Pathways. mSystems 2021; 6:e0033621. [PMID: 34184910 PMCID: PMC8269223 DOI: 10.1128/msystems.00336-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pattern recognition receptors (PRRs) form the front line of defense against pathogens. Many of the molecular mechanisms that facilitate PRR signaling have been characterized in detail, which is critical for the development of accurate PRR pathway models at the molecular interaction level. These models could support the development of therapeutics for numerous diseases, including sepsis and COVID-19. This review describes the molecular mechanisms of the principal signaling interactions of the Toll-like receptor, STING, MAVS, and inflammasome pathways. A detailed molecular mechanism network is included as Data Set S1 in the supplemental material.
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Affiliation(s)
- Nathan P. Manes
- Functional Cellular Networks Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Aleksandra Nita-Lazar
- Functional Cellular Networks Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
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21
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Clabbers MTB, Holmes S, Muusse TW, Vajjhala PR, Thygesen SJ, Malde AK, Hunter DJB, Croll TI, Flueckiger L, Nanson JD, Rahaman MH, Aquila A, Hunter MS, Liang M, Yoon CH, Zhao J, Zatsepin NA, Abbey B, Sierecki E, Gambin Y, Stacey KJ, Darmanin C, Kobe B, Xu H, Ve T. MyD88 TIR domain higher-order assembly interactions revealed by microcrystal electron diffraction and serial femtosecond crystallography. Nat Commun 2021; 12:2578. [PMID: 33972532 PMCID: PMC8110528 DOI: 10.1038/s41467-021-22590-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 03/18/2021] [Indexed: 02/03/2023] Open
Abstract
MyD88 and MAL are Toll-like receptor (TLR) adaptors that signal to induce pro-inflammatory cytokine production. We previously observed that the TIR domain of MAL (MALTIR) forms filaments in vitro and induces formation of crystalline higher-order assemblies of the MyD88 TIR domain (MyD88TIR). These crystals are too small for conventional X-ray crystallography, but are ideally suited to structure determination by microcrystal electron diffraction (MicroED) and serial femtosecond crystallography (SFX). Here, we present MicroED and SFX structures of the MyD88TIR assembly, which reveal a two-stranded higher-order assembly arrangement of TIR domains analogous to that seen previously for MALTIR. We demonstrate via mutagenesis that the MyD88TIR assembly interfaces are critical for TLR4 signaling in vivo, and we show that MAL promotes unidirectional assembly of MyD88TIR. Collectively, our studies provide structural and mechanistic insight into TLR signal transduction and allow a direct comparison of the MicroED and SFX techniques.
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Affiliation(s)
- Max T B Clabbers
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, Sweden
- Department of Biological Chemistry, University of California Los Angeles, Los Angeles, California, USA
| | - Susannah Holmes
- Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia
| | - Timothy W Muusse
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Parimala R Vajjhala
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Sara J Thygesen
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Alpeshkumar K Malde
- Institute for Glycomics, Griffith University, Southport, Queensland, Australia
| | - Dominic J B Hunter
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- EMBL Australia Node in Single Molecule Science, University of New South Wales, Kensington, New South Wales, Australia
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Tristan I Croll
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Leonie Flueckiger
- Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia
| | - Jeffrey D Nanson
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Md Habibur Rahaman
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Andrew Aquila
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California, USA
| | - Mark S Hunter
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California, USA
| | - Mengning Liang
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California, USA
| | - Chun Hong Yoon
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California, USA
| | - Jingjing Zhao
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, Sweden
| | - Nadia A Zatsepin
- Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia
| | - Brian Abbey
- Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia
| | - Emma Sierecki
- EMBL Australia Node in Single Molecule Science, University of New South Wales, Kensington, New South Wales, Australia
| | - Yann Gambin
- EMBL Australia Node in Single Molecule Science, University of New South Wales, Kensington, New South Wales, Australia
| | - Katryn J Stacey
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Connie Darmanin
- Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia.
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia.
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia.
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia.
| | - Hongyi Xu
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, Sweden.
| | - Thomas Ve
- Institute for Glycomics, Griffith University, Southport, Queensland, Australia.
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22
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Abstract
Amyloids are β-sheet-rich protein polymers that can be pathological or display a variety of biological roles. In filamentous fungi, specific immune receptors activate programmed cell death execution proteins through a process of amyloid templating akin to prion propagation. In filamentous fungi, NLR-based signalosomes activate downstream membrane-targeting cell death-inducing proteins by a mechanism of amyloid templating. In the species Podospora anserina, two such signalosomes, NWD2/HET-S and FNT1/HELLF, have been described. An analogous system involving a distinct amyloid signaling motif, termed PP, was also identified in the genome of the species Chaetomium globosum and studied using heterologous expression in Podospora anserina. The PP motif bears resemblance to the RIP homotypic interaction motif (RHIM) and to RHIM-like motifs controlling necroptosis in mammals and innate immunity in flies. We identify here a third NLR signalosome in Podospora anserina comprising a PP motif and organized as a two-gene cluster encoding an NLR and an HELL domain cell death execution protein termed HELLP. We show that the PP motif region of HELLP forms a prion we term [π] and that [π] prions trigger the cell death-inducing activity of full-length HELLP. We detect no prion cross-seeding between HET-S, HELLF, and HELLP amyloid motifs. In addition, we find that, like PP motifs, RHIMs from human RIP1 and RIP3 kinases are able to form prions in Podospora and that [π] and [Rhim] prions partially cross-seed. Our study shows that Podospora anserina displays three independent cell death-inducing amyloid signalosomes. Based on the described functional similarity between RHIM and PP, it appears likely that these amyloid motifs constitute evolutionarily related cell death signaling modules.
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Rodríguez Gama A, Miller T, Halfmann R. Mechanics of a molecular mousetrap-nucleation-limited innate immune signaling. Biophys J 2021; 120:1150-1160. [PMID: 33460595 PMCID: PMC8059202 DOI: 10.1016/j.bpj.2021.01.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 01/05/2021] [Accepted: 01/07/2021] [Indexed: 12/17/2022] Open
Abstract
Innate immune responses, such as cell death and inflammatory signaling, are typically switch-like in nature. They also involve "prion-like" self-templating polymerization of one or more signaling proteins into massive macromolecular assemblies known as signalosomes. Despite the wealth of atomic-resolution structural information on signalosomes, how the constituent polymers nucleate and whether the switch-like nature of that event at the molecular scale relates to the digital nature of innate immune signaling at the cellular scale remains unknown. In this perspective, we review current knowledge of innate immune signalosome assembly, with an emphasis on structural constraints that allow the proteins to accumulate in inactive soluble forms poised for abrupt polymerization. We propose that structurally encoded nucleation barriers to protein polymerization kinetically regulate the corresponding pathways, which allows for extremely sensitive, rapid, and decisive signaling upon pathogen detection. We discuss how nucleation barriers satisfy the rigorous on-demand functions of the innate immune system but also predispose the system to precocious activation that may contribute to progressive age-associated inflammation.
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Affiliation(s)
| | - Tayla Miller
- Stowers Institute for Medical Research, Kansas City, Missouri
| | - Randal Halfmann
- Stowers Institute for Medical Research, Kansas City, Missouri; Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas.
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24
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Song W, Forderer A, Yu D, Chai J. Structural biology of plant defence. THE NEW PHYTOLOGIST 2021; 229:692-711. [PMID: 32880948 DOI: 10.1111/nph.16906] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 07/14/2020] [Indexed: 06/11/2023]
Abstract
Plants employ the innate immune system to discriminate between self and invaders through two types of immune receptors, one on the plasma membrane and the other in the intracellular space. The immune receptors on the plasma membrane are pattern recognition receptors (PRRs) that can perceive pathogen-associated molecular patterns (PAMPs) or host-derived damage-associated molecular patterns (DAMPs) leading to pattern-triggered immunity (PTI). Particular pathogens are capable of overcoming PTI by secreting specific effectors into plant cells to perturb different components of PTI signalling through various mechanisms. Most of the immune receptors from the intracellular space are the nucleotide-binding leucine-rich repeat receptors (NLRs), which specifically recognize pathogen-secreted effectors to mediate effector-triggered immunity (ETI). In this review, we will summarize recent progress in structural studies of PRRs, NLRs, and effectors, and discuss how these studies shed light on ligand recognition and activation mechanisms of the two types of immune receptors and the diversified mechanisms used by effectors to manipulate plant immune signalling.
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Affiliation(s)
- Wen Song
- Max-Planck Institute for Plant Breeding Research, Cologne, 50829, Germany
- Institute of Biochemistry, University of Cologne, Cologne, 50923, Germany
| | - Alexander Forderer
- Max-Planck Institute for Plant Breeding Research, Cologne, 50829, Germany
- Institute of Biochemistry, University of Cologne, Cologne, 50923, Germany
| | - Dongli Yu
- Max-Planck Institute for Plant Breeding Research, Cologne, 50829, Germany
- Institute of Biochemistry, University of Cologne, Cologne, 50923, Germany
| | - Jijie Chai
- Max-Planck Institute for Plant Breeding Research, Cologne, 50829, Germany
- Institute of Biochemistry, University of Cologne, Cologne, 50923, Germany
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25
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Makarova KS, Timinskas A, Wolf YI, Gussow AB, Siksnys V, Venclovas Č, Koonin EV. Evolutionary and functional classification of the CARF domain superfamily, key sensors in prokaryotic antivirus defense. Nucleic Acids Res 2020; 48:8828-8847. [PMID: 32735657 DOI: 10.1093/nar/gkaa635] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 07/13/2020] [Accepted: 07/16/2020] [Indexed: 12/24/2022] Open
Abstract
CRISPR-associated Rossmann Fold (CARF) and SMODS-associated and fused to various effector domains (SAVED) are key components of cyclic oligonucleotide-based antiphage signaling systems (CBASS) that sense cyclic oligonucleotides and transmit the signal to an effector inducing cell dormancy or death. Most of the CARFs are components of a CBASS built into type III CRISPR-Cas systems, where the CARF domain binds cyclic oligoA (cOA) synthesized by Cas10 polymerase-cyclase and allosterically activates the effector, typically a promiscuous ribonuclease. Additionally, this signaling pathway includes a ring nuclease, often also a CARF domain (either the sensor itself or a specialized enzyme) that cleaves cOA and mitigates dormancy or death induction. We present a comprehensive census of CARF and SAVED domains in bacteria and archaea, and their sequence- and structure-based classification. There are 10 major families of CARF domains and multiple smaller groups that differ in structural features, association with distinct effectors, and presence or absence of the ring nuclease activity. By comparative genome analysis, we predict specific functions of CARF and SAVED domains and partition the CARF domains into those with both sensor and ring nuclease functions, and sensor-only ones. Several families of ring nucleases functionally associated with sensor-only CARF domains are also predicted.
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Affiliation(s)
- Kira S Makarova
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA
| | - Albertas Timinskas
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Yuri I Wolf
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA
| | - Ayal B Gussow
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA
| | - Virginijus Siksnys
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Česlovas Venclovas
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA
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26
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Azar DF, Haas M, Fedosyuk S, Rahaman MH, Hedger A, Kobe B, Skern T. Vaccinia Virus Immunomodulator A46: Destructive Interactions with MAL and MyD88 Shown by Negative-Stain Electron Microscopy. Structure 2020; 28:1271-1287.e5. [PMID: 33035450 DOI: 10.1016/j.str.2020.09.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 07/27/2020] [Accepted: 09/17/2020] [Indexed: 12/15/2022]
Abstract
Vaccinia virus A46 is an anti-inflammatory and non-anti-apoptotic, two-domain member of the poxviral Bcl-2-like protein family that inhibits the cellular innate immune response at the level of the Toll/interleukin-1 receptor (TIR) domain-containing TLR adaptor proteins MAL, MyD88, TRAM, and TRIF. The mechanism of interaction of A46 with its targets has remained unclear. The TIR domains of MAL and MyD88 have been shown to signal by forming filamentous assemblies. We show a clear concentration-dependent destruction of both of these assemblies by A46 by means of negative-stain electron microscopy from molar ratios of 1:15 for MAL and 1:30 for MyD88. Using targeted mutagenesis and protein-protein crosslinking, we show that A46 interacts with MAL and MyD88 through several facets, including residues on helices α1 and α7 and the C-terminal flexible region. We propose a model in which A46 targets the MAL and MyD88 signalosome intra-strand interfaces and gradually destroys their assemblies in a concentration-dependent manner.
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Affiliation(s)
- Daniel F Azar
- Max Perutz Labs, Medical University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
| | - Meryl Haas
- Max Perutz Labs, Medical University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
| | - Sofiya Fedosyuk
- Max Perutz Labs, Medical University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria; Jenner Institute, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Md Habibur Rahaman
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD 4072, Australia
| | - Andrew Hedger
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD 4072, Australia
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD 4072, Australia
| | - Tim Skern
- Max Perutz Labs, Medical University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria.
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27
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The Evolutionary Origins of Programmed Cell Death Signaling. Cold Spring Harb Perspect Biol 2020; 12:cshperspect.a036442. [PMID: 31818855 DOI: 10.1101/cshperspect.a036442] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Programmed cell death (PCD) pathways are found in many phyla, ranging from developmentally programmed apoptosis in animals to cell-autonomous programmed necrosis pathways that limit the spread of biotrophic pathogens in multicellular assemblies. Prominent examples for the latter include animal necroptosis and pyroptosis, plant hypersensitive response (HR), and fungal heterokaryon incompatibility (HI) pathways. PCD pathways in the different kingdoms show fundamental differences in execution mechanism, morphology of the dying cells, and in the biological sequelae. Nevertheless, recent studies have revealed remarkable evolutionary parallels, including a striking sequence relationship between the "HeLo" domains found in the pore-forming components of necroptosis and some types of plant HR and fungal HI pathways. Other PCD execution components show cross-kingdom conservation as well, or are derived from prokaryotic ancestors. The currently available data suggest a model, wherein the primordial eukaryotic PCD pathway used proteins similar to present-day plant R-proteins and caused necrotic cell death by direct action of Toll and IL-1 receptor (TIR) and HeLo-like domains.
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28
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Lapin D, Bhandari DD, Parker JE. Origins and Immunity Networking Functions of EDS1 Family Proteins. ANNUAL REVIEW OF PHYTOPATHOLOGY 2020; 58:253-276. [PMID: 32396762 DOI: 10.1146/annurev-phyto-010820-012840] [Citation(s) in RCA: 97] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The EDS1 family of structurally unique lipase-like proteins EDS1, SAG101, and PAD4 evolved in seed plants, on top of existing phytohormone and nucleotide-binding-leucine-rich-repeat (NLR) networks, to regulate immunity pathways against host-adapted biotrophic pathogens. Exclusive heterodimers between EDS1 and SAG101 or PAD4 create essential surfaces for resistance signaling. Phylogenomic information, together with functional studies in Arabidopsis and tobacco, identify a coevolved module between the EDS1-SAG101 heterodimer and coiled-coil (CC) HET-S and LOP-B (CCHELO) domain helper NLRs that is recruited by intracellular Toll-interleukin1-receptor (TIR) domain NLR receptors to confer host cell death and pathogen immunity. EDS1-PAD4 heterodimers have a different and broader activity in basal immunity that transcriptionally reinforces local and systemic defenses triggered by various NLRs. Here, we consider EDS1 family protein functions across seed plant lineages in the context of networking with receptor and helper NLRs and downstream resistance machineries. The different modes of action and pathway connectivities of EDS1 family members go some way to explaining their central role in biotic stress resilience.
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Affiliation(s)
- Dmitry Lapin
- Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, 50829 Cologne, Germany;
- Cologne-Düsseldorf Cluster of Excellence on Plant Sciences (CEPLAS), 40225 Düsseldorf, Germany
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, Michigan 48824, USA
| | - Deepak D Bhandari
- Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, 50829 Cologne, Germany;
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, Michigan 48824, USA
| | - Jane E Parker
- Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, 50829 Cologne, Germany;
- Cologne-Düsseldorf Cluster of Excellence on Plant Sciences (CEPLAS), 40225 Düsseldorf, Germany
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29
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Bayless AM, Nishimura MT. Enzymatic Functions for Toll/Interleukin-1 Receptor Domain Proteins in the Plant Immune System. Front Genet 2020; 11:539. [PMID: 32582284 PMCID: PMC7282519 DOI: 10.3389/fgene.2020.00539] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Accepted: 05/04/2020] [Indexed: 01/09/2023] Open
Abstract
Rationally engineered improvements to crop plants will be needed to keep pace with increasing demands placed on agricultural systems by population growth and climate change. Engineering of plant immune systems provides an opportunity to increase yields by limiting losses to pathogens. Intracellular immune receptors are commonly used as agricultural disease resistance traits. Despite their importance, how intracellular immune receptors confer disease resistance is still unknown. One major class of immune receptors in dicots contains a Toll/Interleukin-1 Receptor (TIR) domain. The mechanisms of TIR-containing proteins during plant immunity have remained elusive. The TIR domain is an ancient module found in archaeal, bacterial and eukaryotic proteins. In animals, TIR domains serve a structural role by generating innate immune signaling complexes. The unusual animal TIR-protein, SARM1, was recently discovered to function instead as an enzyme that depletes cellular NAD+ (nicotinamide adenine dinucleotide) to trigger axonal cell death. Two recent reports have found that plant TIR proteins also have the ability to cleave NAD+. This presents a new paradigm from which to consider how plant TIR immune receptors function. Here, we will review recent reports of the structure and function of TIR-domain containing proteins. Intriguingly, it appears that TIR proteins in all kingdoms may use similar enzymatic mechanisms in a variety of cell death and immune pathways. We will also discuss TIR structure–function hypotheses in light of the recent publication of the ZAR1 resistosome structure. Finally, we will explore the evolutionary context of plant TIR-containing proteins and their downstream signaling components across phylogenies and the functional implications of these findings.
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Affiliation(s)
- Adam M Bayless
- Department of Biology, Colorado State University, Fort Collins, CO, United States
| | - Marc T Nishimura
- Department of Biology, Colorado State University, Fort Collins, CO, United States
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30
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Figley MD, DiAntonio A. The SARM1 axon degeneration pathway: control of the NAD + metabolome regulates axon survival in health and disease. Curr Opin Neurobiol 2020; 63:59-66. [PMID: 32311648 DOI: 10.1016/j.conb.2020.02.012] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 02/20/2020] [Accepted: 02/25/2020] [Indexed: 02/06/2023]
Abstract
Axons are essential for nervous system function and axonal pathology is a common hallmark of many neurodegenerative diseases. Over a century and a half after the original description of Wallerian axon degeneration, advances over the past five years have heralded the emergence of a comprehensive, mechanistic model of an endogenous axon degenerative process that can be activated by both injury and disease. Axonal integrity is maintained by the opposing actions of the survival factors NMNAT2 and STMN2 and pro-degenerative molecules DLK and SARM1. The balance between axon survival and self-destruction is intimately tied to axonal NAD+ metabolism. These mechanistic insights may enable axon-protective therapies for a variety of human neurodegenerative diseases including peripheral neuropathy, traumatic brain injury and potentially ALS and Parkinson's.
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Affiliation(s)
- Matthew D Figley
- Department of Developmental Biology, Washington University School of Medicine in St. Louis, 660 Euclid Avenue, St. Louis, MO 63110, USA
| | - Aaron DiAntonio
- Department of Developmental Biology, Washington University School of Medicine in St. Louis, 660 Euclid Avenue, St. Louis, MO 63110, USA; Needleman Center for Neurometabolism and Axonal Therapeutics, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA.
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31
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Axon degeneration: mechanistic insights lead to therapeutic opportunities for the prevention and treatment of peripheral neuropathy. Pain 2020; 160 Suppl 1:S17-S22. [PMID: 31008845 DOI: 10.1097/j.pain.0000000000001528] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Peripheral neuropathy is the most common neurodegenerative disease affecting hundreds of millions of patients worldwide and is an important cause of chronic pain. Typical peripheral neuropathies are characterized by dysesthesias including numbness, crawling skin, a sensation of "pins and needles," and burning and stabbing pain. In addition, peripheral neuropathy can affect the motor and autonomic systems leading to symptoms such as weakness, constipation, and dysregulation of blood pressure. Peripheral neuropathies can be either hereditary or acquired and are a common consequence of diabetes and treatment with chemotherapy agents. Many neuropathies are due to degeneration of long axons; however, the mechanisms driving axon loss were unknown, and so no therapies are available to preserve vulnerable axons and prevent the development of peripheral neuropathy. With the recent identification of SARM1 as an injury-activated NADase enzyme that triggers axon degeneration, there is now a coherent picture emerging for the mechanism of axonal self-destruction. Here, we will present evidence that inhibiting the SARM1 pathway can prevent the development of peripheral neuropathy, describe the emerging mechanistic understanding of the axon degeneration program, and discuss how these mechanistic insights may be translated to the clinic for the prevention and treatment of peripheral neuropathy and other neurodegenerative disorders.
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32
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Toshchakov VY, Neuwald AF. A survey of TIR domain sequence and structure divergence. Immunogenetics 2020; 72:181-203. [PMID: 32002590 PMCID: PMC7075850 DOI: 10.1007/s00251-020-01157-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 01/20/2020] [Indexed: 12/31/2022]
Abstract
Toll-interleukin-1R resistance (TIR) domains are ubiquitously present in all forms of cellular life. They are most commonly found in signaling proteins, as units responsible for signal-dependent formation of protein complexes that enable amplification and spatial propagation of the signal. A less common function of TIR domains is their ability to catalyze nicotinamide adenine dinucleotide degradation. This survey analyzes 26,414 TIR domains, automatically classified based on group-specific sequence patterns presumably determining biological function, using a statistical approach termed Bayesian partitioning with pattern selection (BPPS). We examine these groups and patterns in the light of available structures and biochemical analyses. Proteins within each of thirteen eukaryotic groups (10 metazoans and 3 plants) typically appear to perform similar functions, whereas proteins within each prokaryotic group typically exhibit diverse domain architectures, suggesting divergent functions. Groups are often uniquely characterized by structural fold variations associated with group-specific sequence patterns and by herein identified sequence motifs defining TIR domain functional divergence. For example, BPPS identifies, in helices C and D of TIRAP and MyD88 orthologs, conserved surface-exposed residues apparently responsible for specificity of TIR domain interactions. In addition, BPPS clarifies the functional significance of the previously described Box 2 and Box 3 motifs, each of which is a part of a larger, group-specific block of conserved, intramolecularly interacting residues.
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Affiliation(s)
- Vladimir Y Toshchakov
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA.
| | - Andrew F Neuwald
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
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33
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Burdett H, Bentham AR, Williams SJ, Dodds PN, Anderson PA, Banfield MJ, Kobe B. The Plant "Resistosome": Structural Insights into Immune Signaling. Cell Host Microbe 2019; 26:193-201. [PMID: 31415752 DOI: 10.1016/j.chom.2019.07.020] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Plant innate immunity is triggered via direct or indirect recognition of pathogen effectors by the NLR family immune receptors. Mechanistic understanding of plant NLR function has relied on structural information from individual NLR domains and inferences from studies on animal NLRs. Recent reports of the cryo-EM structures of the Arabidopsis plant immune receptor ZAR1 in monomeric inactive and transition states, as well as the active oligomeric state or the "resistosome," have afforded a quantum leap in our understanding of how plant NLRs function. In this Review, we outline the recent structural findings and examine their implications for the activation of plant immune receptors more broadly. We also discuss how NLR signaling in plants, as illustrated by the ZAR1 structure, is analogous to innate immune receptor signaling mechanisms across kingdoms, drawing particular attention to the concept of signaling by cooperative assembly formation.
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Affiliation(s)
- Hayden Burdett
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD 4072, Australia
| | - Adam R Bentham
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Simon J Williams
- Plant Sciences Division, Research School of Biology, The Australian National University, Canberra 2601, Australia
| | - Peter N Dodds
- Agriculture and Food, Commonwealth Scientific and Industrial Research Organisation, Canberra, ACT 2601, Australia
| | - Peter A Anderson
- College of Sciences, Flinders University, Adelaide, SA 5001, Australia
| | - Mark J Banfield
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD 4072, Australia.
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34
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Voss M, Toelzer C, Bhandari DD, Parker JE, Niefind K. Arabidopsis immunity regulator EDS1 in a PAD4/SAG101-unbound form is a monomer with an inherently inactive conformation. J Struct Biol 2019; 208:107390. [PMID: 31550533 DOI: 10.1016/j.jsb.2019.09.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 09/18/2019] [Accepted: 09/20/2019] [Indexed: 11/25/2022]
Abstract
In plant innate immunity, enhanced disease susceptibility 1 (EDS1) integrates all pathogen-induced signals transmitted by TIR-type NLR receptors. Driven by an N-terminal α/β-hydrolase-fold domain with a protruding interaction helix, EDS1 assembles with two homologs, phytoalexin-deficient 4 (PAD4) and senescence-associated gene 101 (SAG101). The resulting heterodimers are critical for EDS1 function and structurally well characterized. Here, we resolve solution and crystal structures of unbound Arabidopsis thaliana EDS1 (AtEDS1) using nanobodies for crystallization. These structures, together with gel filtration and immunoprecipitation data, show that PAD4/SAG101-unbound AtEDS1 is stable as a monomer and does not form the homodimers recorded in public databases. Its PAD4/SAG101 anchoring helix is disordered unless engaged in protein/protein interactions. As in the complex with SAG101, monomeric AtEDS1 has a substrate-inaccessible esterase triad with a blocked oxyanion hole and without space for a covalent acyl intermediate. These new structures suggest that the AtEDS1 monomer represents an inactive or pre-activated ground state.
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Affiliation(s)
- Martin Voss
- University of Cologne, Department of Chemistry, Institute of Biochemistry, Zülpicher Str. 47, D-50674 Cologne, Germany
| | - Christine Toelzer
- University of Cologne, Department of Chemistry, Institute of Biochemistry, Zülpicher Str. 47, D-50674 Cologne, Germany
| | - Deepak D Bhandari
- Department of Plant-Microbe Interactions, Max-Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, D-50829 Cologne, Germany
| | - Jane E Parker
- Department of Plant-Microbe Interactions, Max-Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, D-50829 Cologne, Germany
| | - Karsten Niefind
- University of Cologne, Department of Chemistry, Institute of Biochemistry, Zülpicher Str. 47, D-50674 Cologne, Germany.
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Jubic LM, Saile S, Furzer OJ, El Kasmi F, Dangl JL. Help wanted: helper NLRs and plant immune responses. CURRENT OPINION IN PLANT BIOLOGY 2019; 50:82-94. [PMID: 31063902 DOI: 10.1016/j.pbi.2019.03.013] [Citation(s) in RCA: 153] [Impact Index Per Article: 30.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 03/13/2019] [Accepted: 03/25/2019] [Indexed: 05/09/2023]
Abstract
Plant nucleotide-binding domain and leucine-rich repeat-containing (NLR) proteins function as intracellular receptors in response to pathogens and activate effector-triggered immune responses (ETI). The activation of some sensor NLRs (sNLR) by their corresponding pathogen effector is well studied. However, the mechanisms by which the recently defined helper NLRs (hNLR) function to transduce sNLR activation into ETI-associated cell death and disease resistance remains poorly understood. We briefly summarize recent examples of sNLR activation and we then focus on hNLR requirements in sNLR-initiated immune responses. We further discuss how shared sequence homology with fungal self-incompatibility proteins and the mammalian mixed lineage kinase domain like pseudokinase (MLKL) proteins informs a plausible model for the structure and function of an ancient clade of plant hNLRs, called RNLs.
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Affiliation(s)
- Lance M Jubic
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, USA; Howard Hughes Medical Institute, University of North Carolina at Chapel Hill, Chapel Hill, USA
| | - Svenja Saile
- ZMBP-Plant Physiology, University of Tübingen, Tübingen, Germany
| | - Oliver J Furzer
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, USA
| | - Farid El Kasmi
- ZMBP-Plant Physiology, University of Tübingen, Tübingen, Germany.
| | - Jeffery L Dangl
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, USA; Howard Hughes Medical Institute, University of North Carolina at Chapel Hill, Chapel Hill, USA; Carolina Center for Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, USA; Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, USA; Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, USA.
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Animal NLRs continue to inform plant NLR structure and function. Arch Biochem Biophys 2019; 670:58-68. [PMID: 31071301 DOI: 10.1016/j.abb.2019.05.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 04/10/2019] [Accepted: 05/01/2019] [Indexed: 12/22/2022]
Abstract
Plant NLRs share many of the structural hallmarks of their animal counterparts. At a functional level, the central nucleotide-binding pocket appears to have binding and hydrolysis activities, similar to that of animal NLRs. The TIR domains of plant NLRs have been shown to self-associate, and there is emerging evidence that full-length plant NLRs may do so as well. It is therefore tempting to speculate that plant NLRs may form higher-order complexes similar to those of the mammalian inflammasome. Here we review the available knowledge on structure-function relationships in plant NLRs, focusing on how the information available on animal NLRs informs the mechanism of plant NLR function, and highlight the evidence that innate immunity signalling pathways in multicellular organisms often require the formation of higher-order protein complexes.
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Gentle IE. Supramolecular Complexes in Cell Death and Inflammation and Their Regulation by Autophagy. Front Cell Dev Biol 2019; 7:73. [PMID: 31131275 PMCID: PMC6509160 DOI: 10.3389/fcell.2019.00073] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 04/10/2019] [Indexed: 12/23/2022] Open
Abstract
Signaling activation is a tightly regulated process involving myriad posttranslational modifications such as phosphorylation/dephosphorylation, ubiquitylation/deubiquitylation, proteolytical cleavage events as well as translocation of proteins to new compartments within the cell. In addition to each of these events potentially regulating individual proteins, the assembly of very large supramolecular complexes has emerged as a common theme in signal transduction and is now known to regulate many signaling events. This is particularly evident in pathways regulating both inflammation and cell death/survival. Regulation of the assembly and silencing of these complexes plays important roles in immune signaling and inflammation and the fate of cells to either die or survive. Here we will give a summary of some of the better studied supramolecular complexes involved in inflammation and cell death, particularly with a focus on diseases caused by their autoactivation and the role autophagy either plays or may be playing in their regulation.
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Affiliation(s)
- Ian E Gentle
- Faculty of Medicine, Institute of Medical Microbiology and Hygiene, Medical Center, University of Freiburg, Freiburg im Breisgau, Germany
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