1
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O'Neill N, Meng M, Chaqour B, Dine K, Sarabu N, Pham JC, Shindler KS, Ross AG. Comparison of SNCG and NEFH Promoter-Driven Expression of Human SIRT1 Expression in a Mouse Model of Glaucoma. Transl Vis Sci Technol 2024; 13:37. [PMID: 39177995 DOI: 10.1167/tvst.13.8.37] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/24/2024] Open
Abstract
Purpose Adeno-associated virus (AAV) demonstrates promise in delivering therapeutic genes to retinal ganglion cells (RGCs). Delivery of neuroprotective genes is constrained by packaging size and/or cell selectivity. This study compares the ability of the RGC-selective gamma-synuclein (SNCG) promoter and the smaller RGC-selective neurofilament heavy chain (NEFH) promoter, as well as portions of the RGC-selective atonal bHLH transcription factor 7 (ATOH7) enhancer, to drive gene expression in RGCs. Methods AAV2 constructs with green fluorescent protein (GFP) or human sirtuin 1 (hSIRT1) driven by cytomegalovirus (CMV) enhancer and NEFH promoter (AAV2-eCMV-NEFH) or distal active sequences of the ATOH7 enhancer (DiATOH7) with the SNCG promoter (AAV2-DiATOH7-SNCG) were intravitreally injected into C57BL/6J mice. RGCs were immunolabeled with Brn3a antibodies and counted. AAV constructs with the utmost transduction efficiency were used to test the therapeutic efficacy of the hSIRT1 gene in 12-week-old C57BL/6J mice subjected to microbead (MB)-induced intraocular pressure (IOP) elevation. Visual function was measured using optokinetic responses (OKRs). Results The eGFP transduction efficiency of AAV2-eCMV-NEFH was similar to that of AAV2-eCMV-SNCG and AAV2-DiATOH7-SNCG. When combined with the SNCG promoter, a larger ATOH7 enhancer was less efficient than the shorter DiATOH7 enhancer. Similarly, the hSIRT1 efficiency of AAV2-eCMV-NEFH was similar to that of AAV2-eCMV-SNCG. The latter two vectors were equally efficient in increasing RGC survival and improving visual function in the mouse model of MB-induced IOP elevation. Conclusions SNCG and NEFH promoters represent two equally efficient and comparable RGC selective promoter sequences; however, the NEFH promoter offers a smaller packaging size. Translational Relevance Smaller enhancer-promoter combinations can be used to deliver larger genes in human cells and for treatment in optic neuropathies including glaucoma.
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Affiliation(s)
- Nuala O'Neill
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
| | - Miranda Meng
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
| | - Brahim Chaqour
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
- F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Kimberly Dine
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
- F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Neha Sarabu
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
| | - Jennifer C Pham
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
- F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Kenneth S Shindler
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
- F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
| | - Ahmara G Ross
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
- F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
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2
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McGuinness HY, Gu W, Shi Y, Kobe B, Ve T. SARM1-Dependent Axon Degeneration: Nucleotide Signaling, Neurodegenerative Disorders, Toxicity, and Therapeutic Opportunities. Neuroscientist 2024; 30:473-492. [PMID: 37002660 PMCID: PMC11282687 DOI: 10.1177/10738584231162508] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/27/2024]
Abstract
Axons are an essential component of the nervous system, and axon degeneration is an early feature of many neurodegenerative disorders. The NAD+ metabolome plays an essential role in regulating axonal integrity. Axonal levels of NAD+ and its precursor NMN are controlled in large part by the NAD+ synthesizing survival factor NMNAT2 and the pro-neurodegenerative NADase SARM1, whose activation triggers axon destruction. SARM1 has emerged as a promising axon-specific target for therapeutic intervention, and its function, regulation, structure, and role in neurodegenerative diseases have been extensively characterized in recent years. In this review, we first introduce the key molecular players involved in the SARM1-dependent axon degeneration program. Next, we summarize recent major advances in our understanding of how SARM1 is kept inactive in healthy neurons and how it becomes activated in injured or diseased neurons, which has involved important insights from structural biology. Finally, we discuss the role of SARM1 in neurodegenerative disorders and environmental neurotoxicity and its potential as a therapeutic target.
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Affiliation(s)
- Helen Y. McGuinness
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Saint Lucia, Australia
| | - Weixi Gu
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Saint Lucia, Australia
| | - Yun Shi
- Institute for Glycomics, Griffith University, Gold Coast, Australia
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Saint Lucia, Australia
| | - Thomas Ve
- Institute for Glycomics, Griffith University, Gold Coast, Australia
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3
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Dingwall CB, Sasaki Y, Strickland A, Summers DW, Bloom AJ, DiAntonio A, Milbrandt J. Suppressing phagocyte activation by overexpressing the phosphatidylserine lipase ABHD12 preserves sarmopathic nerves. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.20.599919. [PMID: 38979309 PMCID: PMC11230269 DOI: 10.1101/2024.06.20.599919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Programmed axon degeneration (AxD) is a key feature of many neurodegenerative diseases. In healthy axons, the axon survival factor NMNAT2 inhibits SARM1, the central executioner of AxD, preventing it from initiating the rapid local NAD+ depletion and metabolic catastrophe that precipitates axon destruction. Because these components of the AxD pathway act within neurons, it was also assumed that the timetable of AxD was set strictly by a cell-intrinsic mechanism independent of neuron-extrinsic processes later activated by axon fragmentation. However, using a rare human disease model of neuropathy caused by hypomorphic NMNAT2 mutations and chronic SARM1 activation (sarmopathy), we demonstrated that neuronal SARM1 can initiate macrophage-mediated axon elimination long before stressed-but-viable axons would otherwise succumb to cell-intrinsic metabolic failure. Investigating potential SARM1-dependent signals that mediate macrophage recognition and/or engulfment of stressed-but-viable axons, we found that chronic SARM1 activation triggers axonal blebbing and dysregulation of phosphatidylserine (PS), a potent phagocyte immunomodulatory molecule. Neuronal expression of the phosphatidylserine lipase ABDH12 suppresses nerve macrophage activation, preserves motor axon integrity, and rescues motor function in this chronic sarmopathy model. We conclude that PS dysregulation is an early SARM1-dependent axonal stress signal, and that blockade of phagocytic recognition and engulfment of stressed-but-viable axons could be an attractive therapeutic target for management of neurological disorders involving SARM1 activation.
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4
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Sugisawa R, Shanahan KA, Davis GM, Davey GP, Bowie AG. SARM1 regulates pro-inflammatory cytokine expression in human monocytes by NADase-dependent and -independent mechanisms. iScience 2024; 27:109940. [PMID: 38832024 PMCID: PMC11145347 DOI: 10.1016/j.isci.2024.109940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Revised: 03/14/2024] [Accepted: 05/06/2024] [Indexed: 06/05/2024] Open
Abstract
SARM1 is a Toll-IL-1 receptor (TIR) domain-containing protein with roles in innate immunity and neuronal death in diverse organisms. Unlike other innate immune TIR proteins that function as adaptors for Toll-like receptors (TLRs), SARM1 has NADase activity, and this activity regulates murine neuronal cell death. However, whether human SARM1, and its NADase activity, are involved in innate immune regulation remains unclear. Here, we show that human SARM1 regulates proinflammatory cytokine expression in both an NADase-dependent and -independent manner in monocytes. SARM1 negatively regulated TLR4-dependent TNF mRNA induction independently of its NADase activity. In contrast, SARM1 inhibited IL-1β secretion through both NADase-dependent inhibition of pro-IL-1β expression, and NADase-independent suppression of the NLRP3 inflammasome and hence processing of pro-IL-1β to mature IL-1β. Our study reveals multiple mechanisms whereby SARM1 regulates pro-inflammatory cytokines in human monocytes and shows, compared to other mammalian TIR proteins, a distinct NADase-dependent role for SARM1 in innate immunity.
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Affiliation(s)
- Ryoichi Sugisawa
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
- Department of Biochemistry, Kindai University Faculty of Medicine, Osaka, Japan
| | - Katharine A. Shanahan
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Gavin M. Davis
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Gavin P. Davey
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Andrew G. Bowie
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
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5
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Hinz FI, Villegas CLM, Roberts JT, Yao H, Gaddam S, Delwig A, Green SA, Fredrickson C, Adrian M, Asuncion RR, Cheung TK, Hayne M, Hackos DH, Rose CM, Richmond D, Hoogenraad CC. Context-Specific Stress Causes Compartmentalized SARM1 Activation and Local Degeneration in Cortical Neurons. J Neurosci 2024; 44:e2424232024. [PMID: 38692735 PMCID: PMC11170950 DOI: 10.1523/jneurosci.2424-23.2024] [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: 12/26/2023] [Revised: 04/21/2024] [Accepted: 04/23/2024] [Indexed: 05/03/2024] Open
Abstract
Sterile alpha and TIR motif containing 1 (SARM1) is an inducible NADase that localizes to mitochondria throughout neurons and senses metabolic changes that occur after injury. Minimal proteomic changes are observed upon either SARM1 depletion or activation, suggesting that SARM1 does not exert broad effects on neuronal protein homeostasis. However, whether SARM1 activation occurs throughout the neuron in response to injury and cell stress remains largely unknown. Using a semiautomated imaging pipeline and a custom-built deep learning scoring algorithm, we studied degeneration in both mixed-sex mouse primary cortical neurons and male human-induced pluripotent stem cell-derived cortical neurons in response to a number of different stressors. We show that SARM1 activation is differentially restricted to specific neuronal compartments depending on the stressor. Cortical neurons undergo SARM1-dependent axon degeneration after mechanical transection, and SARM1 activation is limited to the axonal compartment distal to the injury site. However, global SARM1 activation following vacor treatment causes both cell body and axon degeneration. Context-specific stressors, such as microtubule dysfunction and mitochondrial stress, induce axonal SARM1 activation leading to SARM1-dependent axon degeneration and SARM1-independent cell body death. Our data reveal that compartment-specific SARM1-mediated death signaling is dependent on the type of injury and cellular stressor.
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Affiliation(s)
- Flora I Hinz
- Department of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | | | - Jasmine T Roberts
- Department of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Heming Yao
- Biological Research | AI Development, Genentech, Inc., South San Francisco, California 94080
| | - Shreya Gaddam
- Biological Research | AI Development, Genentech, Inc., South San Francisco, California 94080
| | - Anton Delwig
- Departments of Biochemical and Cellular Pharmacology, Genentech, Inc., South San Francisco, California 94080
| | - Samantha A Green
- Discovery Chemistry, Genentech, Inc., South San Francisco, California 94080
| | - Craig Fredrickson
- Department of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Max Adrian
- Pathology, Genentech, Inc., South San Francisco, California 94080
| | - Raymond R Asuncion
- Transgenic Technology, Genentech, Inc., South San Francisco, California 94080
| | - Tommy K Cheung
- Microchemistry, Proteomics, and Lipidomics, Genentech, Inc., South San Francisco, California 94080
| | - Margaret Hayne
- Department of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - David H Hackos
- Department of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Christopher M Rose
- Microchemistry, Proteomics, and Lipidomics, Genentech, Inc., South San Francisco, California 94080
| | - David Richmond
- Biological Research | AI Development, Genentech, Inc., South San Francisco, California 94080
| | - Casper C Hoogenraad
- Department of Neuroscience, Genentech, Inc., South San Francisco, California 94080
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6
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Velma G, Krider IS, Alves ETM, Courey JM, Laham MS, Thatcher GRJ. Channeling Nicotinamide Phosphoribosyltransferase (NAMPT) to Address Life and Death. J Med Chem 2024; 67:5999-6026. [PMID: 38580317 PMCID: PMC11056997 DOI: 10.1021/acs.jmedchem.3c02112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 02/22/2024] [Accepted: 03/11/2024] [Indexed: 04/07/2024]
Abstract
Nicotinamide phosphoribosyltransferase (NAMPT) catalyzes the rate-limiting step in NAD+ biosynthesis via salvage of NAM formed from catabolism of NAD+ by proteins with NADase activity (e.g., PARPs, SIRTs, CD38). Depletion of NAD+ in aging, neurodegeneration, and metabolic disorders is addressed by NAD+ supplementation. Conversely, NAMPT inhibitors have been developed for cancer therapy: many discovered by phenotypic screening for cancer cell death have low nanomolar potency in cellular models. No NAMPT inhibitor is yet FDA-approved. The ability of inhibitors to act as NAMPT substrates may be associated with efficacy and toxicity. Some 3-pyridyl inhibitors become 4-pyridyl activators or "NAD+ boosters". NAMPT positive allosteric modulators (N-PAMs) and boosters may increase enzyme activity by relieving substrate/product inhibition. Binding to a "rear channel" extending from the NAMPT active site is key for inhibitors, boosters, and N-PAMs. A deeper understanding may fulfill the potential of NAMPT ligands to regulate cellular life and death.
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Affiliation(s)
- Ganga
Reddy Velma
- Department
of Pharmacology & Toxicology, R. Ken Coit College of Pharmacy, University of Arizona, Tucson, Arizona 85721, United States
| | - Isabella S. Krider
- Department
of Chemistry & Biochemistry, University
of Arizona, Tucson, Arizona 85721, United States
| | - Erick T. M. Alves
- Department
of Pharmacology & Toxicology, R. Ken Coit College of Pharmacy, University of Arizona, Tucson, Arizona 85721, United States
| | - Jenna M. Courey
- Department
of Chemistry & Biochemistry, University
of Arizona, Tucson, Arizona 85721, United States
| | - Megan S. Laham
- Department
of Chemistry & Biochemistry, University
of Arizona, Tucson, Arizona 85721, United States
| | - Gregory R. J. Thatcher
- Department
of Pharmacology & Toxicology, R. Ken Coit College of Pharmacy, University of Arizona, Tucson, Arizona 85721, United States
- Department
of Chemistry & Biochemistry, University
of Arizona, Tucson, Arizona 85721, United States
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7
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Guo L, Huang P, Li Z, Shin YC, Yan P, Lu M, Chen M, Xiao Y. Auto-inhibition and activation of a short Argonaute-associated TIR-APAZ defense system. Nat Chem Biol 2024; 20:512-520. [PMID: 37932527 DOI: 10.1038/s41589-023-01478-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Accepted: 10/12/2023] [Indexed: 11/08/2023]
Abstract
Short prokaryotic Ago accounts for most prokaryotic Argonaute proteins (pAgos) and is involved in defending bacteria against invading nucleic acids. Short pAgo associated with TIR-APAZ (SPARTA) has been shown to oligomerize and deplete NAD+ upon guide-mediated target DNA recognition. However, the molecular basis of SPARTA inhibition and activation remains unknown. In this study, we determined the cryogenic electron microscopy structures of Crenotalea thermophila SPARTA in its inhibited, transient and activated states. The SPARTA monomer is auto-inhibited by its acidic tail, which occupies the guide-target binding channel. Guide-mediated target binding expels this acidic tail and triggers substantial conformational changes to expose the Ago-Ago dimerization interface. As a result, SPARTA assembles into an active tetramer, where the four TIR domains are rearranged and packed to form NADase active sites. Together with biochemical evidence, our results provide a panoramic vision explaining SPARTA auto-inhibition and activation and expand understanding of pAgo-mediated bacterial defense systems.
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Affiliation(s)
- Lijie Guo
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
- Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Pingping Huang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
- Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Zhaoxing Li
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
- Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Young-Cheul Shin
- Department of Chemical Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, China
| | - Purui Yan
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
- Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Meiling Lu
- Department of Biochemistry, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Meirong Chen
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China.
- Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing, China.
| | - Yibei Xiao
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China.
- Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing, China.
- Chongqing Innovation Institute of China Pharmaceutical University, Chongqing, China.
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8
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Zhang M, Liu T, Yang J. Skin neuropathy and immunomodulation in diseases. FUNDAMENTAL RESEARCH 2024; 4:218-225. [PMID: 38933512 PMCID: PMC11197692 DOI: 10.1016/j.fmre.2022.08.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 08/14/2022] [Accepted: 08/30/2022] [Indexed: 12/01/2022] Open
Abstract
Skin is a vital barrier tissue of the body. Immune responses in the skin must be precisely controlled, which would otherwise cause severe disease conditions such as psoriasis, atopic dermatitis, or pathogenic infection. Research evidence has increasingly demonstrated the essential roles of neural innervations, i.e., sensory and sympathetic signals, in modulating skin immunity. Notably, neuropathic changes of such neural structures have been observed in skin disease conditions, implicating their direct involvement in various pathological processes. An in-depth understanding of the mechanism underlying skin neuropathy and its immunomodulatory effects could help reveal novel entry points for therapeutic interventions. Here, we summarize the neuroimmune interactions between neuropathic events and skin immunity, highlighting the current knowledge and future perspectives of this emerging research frontier.
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Affiliation(s)
- Manze Zhang
- Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Tingting Liu
- Department of Biochemistry, Weill Cornell Medical College, New York, NY 10065, USA
| | - Jing Yang
- IDG/McGovern Institute for Brain Research, Center for Life Sciences, School of Life Sciences, Peking University, Beijing 100871, China
- Peking University Third Hospital Cancer Center, Beijing 100191, China
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9
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Miyamoto T, Kim C, Chow J, Dugas JC, DeGroot J, Bagdasarian AL, Thottumkara AP, Larhammar M, Calvert ME, Fox BM, Lewcock JW, Kane LA. SARM1 is responsible for calpain-dependent dendrite degeneration in mouse hippocampal neurons. J Biol Chem 2024; 300:105630. [PMID: 38199568 PMCID: PMC10862016 DOI: 10.1016/j.jbc.2024.105630] [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: 07/21/2023] [Revised: 12/10/2023] [Accepted: 12/24/2023] [Indexed: 01/12/2024] Open
Abstract
Sterile alpha and toll/interleukin receptor motif-containing 1 (SARM1) is a critical regulator of axon degeneration that acts through hydrolysis of NAD+ following injury. Recent work has defined the mechanisms underlying SARM1's catalytic activity and advanced our understanding of SARM1 function in axons, yet the role of SARM1 signaling in other compartments of neurons is still not well understood. Here, we show in cultured hippocampal neurons that endogenous SARM1 is present in axons, dendrites, and cell bodies and that direct activation of SARM1 by the neurotoxin Vacor causes not just axon degeneration, but degeneration of all neuronal compartments. In contrast to the axon degeneration pathway defined in dorsal root ganglia, SARM1-dependent hippocampal axon degeneration in vitro is not sensitive to inhibition of calpain proteases. Dendrite degeneration downstream of SARM1 in hippocampal neurons is dependent on calpain 2, a calpain protease isotype enriched in dendrites in this cell type. In summary, these data indicate SARM1 plays a critical role in neurodegeneration outside of axons and elucidates divergent pathways leading to degeneration in hippocampal axons and dendrites.
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Affiliation(s)
| | - Chaeyoung Kim
- Denali Therapeutics Inc, South San Francisco, California, USA
| | - Johann Chow
- Denali Therapeutics Inc, South San Francisco, California, USA
| | - Jason C Dugas
- Denali Therapeutics Inc, South San Francisco, California, USA
| | - Jack DeGroot
- Denali Therapeutics Inc, South San Francisco, California, USA
| | | | | | | | | | - Brian M Fox
- Denali Therapeutics Inc, South San Francisco, California, USA
| | | | - Lesley A Kane
- Denali Therapeutics Inc, South San Francisco, California, USA.
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10
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Locci F, Parker JE. Plant NLR immunity activation and execution: a biochemical perspective. Open Biol 2024; 14:230387. [PMID: 38262605 PMCID: PMC10805603 DOI: 10.1098/rsob.230387] [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: 10/23/2023] [Accepted: 12/15/2023] [Indexed: 01/25/2024] Open
Abstract
Plants deploy cell-surface and intracellular receptors to detect pathogen attack and trigger innate immune responses. Inside host cells, families of nucleotide-binding/leucine-rich repeat (NLR) proteins serve as pathogen sensors or downstream mediators of immune defence outputs and cell death, which prevent disease. Established genetic underpinnings of NLR-mediated immunity revealed various strategies plants adopt to combat rapidly evolving microbial pathogens. The molecular mechanisms of NLR activation and signal transmission to components controlling immunity execution were less clear. Here, we review recent protein structural and biochemical insights to plant NLR sensor and signalling functions. When put together, the data show how different NLR families, whether sensors or signal transducers, converge on nucleotide-based second messengers and cellular calcium to confer immunity. Although pathogen-activated NLRs in plants engage plant-specific machineries to promote defence, comparisons with mammalian NLR immune receptor counterparts highlight some shared working principles for NLR immunity across kingdoms.
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Affiliation(s)
- Federica Locci
- Department of Plant-Microbe Interactions, Max-Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, 50829 Cologne, Germany
| | - Jane E. Parker
- Department of Plant-Microbe Interactions, Max-Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, 50829 Cologne, Germany
- Cologne-Düsseldorf Cluster of Excellence on Plant Sciences (CEPLAS), 40225 Düsseldorf, Germany
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11
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Funakoshi M, Araki T. Mechanism of initiation and regulation of axonal degeneration with special reference to NMNATs and Sarm1. Neurosci Res 2023; 197:3-8. [PMID: 34767875 DOI: 10.1016/j.neures.2021.11.002] [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: 11/01/2021] [Accepted: 11/01/2021] [Indexed: 10/19/2022]
Abstract
Axonal degeneration is observed in a variety of contexts in both the central and peripheral nervous systems. Pathological signaling to regulate the progression of axonal degeneration has long been studied using Wallerian degeneration, the prototypical axonal degradation observed after injury, as a representative model. Understanding metabolism of nicotinamide adenine dinucleotide (NAD+) and the functional regulation of Sarm1 has generated great progress in this field, but there are a number of remaining questions. Here, in this short review, we describe our current understanding of the axonal degeneration mechanism, with special reference to the biology related to wlds mice and Sarm1. Furthermore, variations of axonal degeneration initiation are discussed in order to address the remaining questions needed for mechanistic clarification.
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Affiliation(s)
- Masabumi Funakoshi
- Department of Peripheral Nervous System Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo, 187-8502, Japan
| | - Toshiyuki Araki
- Department of Peripheral Nervous System Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo, 187-8502, Japan.
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12
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Alexandris AS, Koliatsos VE. NAD +, Axonal Maintenance, and Neurological Disease. Antioxid Redox Signal 2023; 39:1167-1184. [PMID: 37503611 PMCID: PMC10715442 DOI: 10.1089/ars.2023.0350] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 05/28/2023] [Indexed: 07/29/2023]
Abstract
Significance: The remarkable geometry of the axon exposes it to unique challenges for survival and maintenance. Axonal degeneration is a feature of peripheral neuropathies, glaucoma, and traumatic brain injury, and an early event in neurodegenerative diseases. Since the discovery of Wallerian degeneration (WD), a molecular program that hijacks nicotinamide adenine dinucleotide (NAD+) metabolism for axonal self-destruction, the complex roles of NAD+ in axonal viability and disease have become research priority. Recent Advances: The discoveries of the protective Wallerian degeneration slow (WldS) and of sterile alpha and TIR motif containing 1 (SARM1) activation as the main instructive signal for WD have shed new light on the regulatory role of NAD+ in axonal degeneration in a growing number of neurological diseases. SARM1 has been characterized as a NAD+ hydrolase and sensor of NAD+ metabolism. The discovery of regulators of nicotinamide mononucleotide adenylyltransferase 2 (NMNAT2) proteostasis in axons, the allosteric regulation of SARM1 by NAD+ and NMN, and the existence of clinically relevant windows of action of these signals has opened new opportunities for therapeutic interventions, including SARM1 inhibitors and modulators of NAD+ metabolism. Critical Issues: Events upstream and downstream of SARM1 remain unclear. Furthermore, manipulating NAD+ metabolism, an overdetermined process crucial in cell survival, for preventing the degeneration of the injured axon may be difficult and potentially toxic. Future Directions: There is a need for clarification of the distinct roles of NAD+ metabolism in axonal maintenance as contrasted to WD. There is also a need to better understand the role of NAD+ metabolism in axonal endangerment in neuropathies, diseases of the white matter, and the early stages of neurodegenerative diseases of the central nervous system. Antioxid. Redox Signal. 39, 1167-1184.
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Affiliation(s)
| | - Vassilis E. Koliatsos
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Neurology, and Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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13
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Waller TJ, Collins CA. Opposing roles of Fos, Raw, and SARM1 in the regulation of axonal degeneration and synaptic structure. Front Cell Neurosci 2023; 17:1283995. [PMID: 38099151 PMCID: PMC10719852 DOI: 10.3389/fncel.2023.1283995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Accepted: 10/30/2023] [Indexed: 12/17/2023] Open
Abstract
Introduction The degeneration of injured axons is driven by conserved molecules, including the sterile armadillo TIR domain-containing protein SARM1, the cJun N-terminal kinase JNK, and regulators of these proteins. These molecules are also implicated in the regulation of synapse development though the mechanistic relationship of their functions in degeneration vs. development is poorly understood. Results and discussion Here, we uncover disparate functional relationships between SARM1 and the transmembrane protein Raw in the regulation of Wallerian degeneration and synaptic growth in motoneurons of Drosophila melanogaster. Our genetic data suggest that Raw antagonizes the downstream output MAP kinase signaling mediated by Drosophila SARM1 (dSarm). This relationship is revealed by dramatic synaptic overgrowth phenotypes at the larval neuromuscular junction when motoneurons are depleted for Raw or overexpress dSarm. While Raw antagonizes the downstream output of dSarm to regulate synaptic growth, it shows an opposite functional relationship with dSarm for axonal degeneration. Loss of Raw leads to decreased levels of dSarm in axons and delayed axonal degeneration that is rescued by overexpression of dSarm, supporting a model that Raw promotes the activation of dSarm in axons. However, inhibiting Fos also decreases dSarm levels in axons but has the opposite outcome of enabling Wallerian degeneration. The combined genetic data suggest that Raw, dSarm, and Fos influence each other's functions through multiple points of regulation to control the structure of synaptic terminals and the resilience of axons to degeneration.
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Affiliation(s)
- Thomas J. Waller
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
| | - Catherine A. Collins
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH, United States
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14
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Klontz E, Obi JO, Wang Y, Glendening G, Carr J, Tsibouris C, Buddula S, Nallar S, Soares AS, Beckett D, Redzic JS, Eisenmesser E, Palm C, Schmidt K, Scudder AH, Obiorah T, Essuman K, Milbrandt J, Diantonio A, Ray K, Snyder MLD, Deredge D, Snyder GA. The structure of NAD + consuming protein Acinetobacter baumannii TIR domain shows unique kinetics and conformations. J Biol Chem 2023; 299:105290. [PMID: 37758001 PMCID: PMC10641520 DOI: 10.1016/j.jbc.2023.105290] [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: 05/25/2023] [Revised: 09/05/2023] [Accepted: 09/13/2023] [Indexed: 09/29/2023] Open
Abstract
Toll-like and interleukin-1/18 receptor/resistance (TIR) domain-containing proteins function as important signaling and immune regulatory molecules. TIR domain-containing proteins identified in eukaryotic and prokaryotic species also exhibit NAD+ hydrolase activity in select bacteria, plants, and mammalian cells. We report the crystal structure of the Acinetobacter baumannii TIR domain protein (AbTir-TIR) with confirmed NAD+ hydrolysis and map the conformational effects of its interaction with NAD+ using hydrogen-deuterium exchange-mass spectrometry. NAD+ results in mild decreases in deuterium uptake at the dimeric interface. In addition, AbTir-TIR exhibits EX1 kinetics indicative of large cooperative conformational changes, which are slowed down upon substrate binding. Additionally, we have developed label-free imaging using the minimally invasive spectroscopic method 2-photon excitation with fluorescence lifetime imaging, which shows differences in bacteria expressing native and mutant NAD+ hydrolase-inactivated AbTir-TIRE208A protein. Our observations are consistent with substrate-induced conformational changes reported in other TIR model systems with NAD+ hydrolase activity. These studies provide further insight into bacterial TIR protein mechanisms and their varying roles in biology.
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Affiliation(s)
- Erik Klontz
- Division of Vaccine Research, Institute of Human Virology, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Juliet O Obi
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland, USA
| | - Yajing Wang
- Division of Vaccine Research, Institute of Human Virology, School of Medicine, University of Maryland, Baltimore, Maryland, USA; Department of Physiology, School of Basic Medical Sciences and Clinical Pharmacy, China Pharmaceutical University, Nanjing, P.R. China
| | - Gabrielle Glendening
- Division of Vaccine Research, Institute of Human Virology, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Jahid Carr
- Division of Vaccine Research, Institute of Human Virology, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Constantine Tsibouris
- Division of Vaccine Research, Institute of Human Virology, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Sahthi Buddula
- Division of Vaccine Research, Institute of Human Virology, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Shreeram Nallar
- Division of Vaccine Research, Institute of Human Virology, School of Medicine, University of Maryland, Baltimore, Maryland, USA; Department of Microbiology and Immunology, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Alexei S Soares
- Brookhaven National Laboratory, National Synchrotron Light Source II, Structural Biology Program, Upton, New York, USA
| | - Dorothy Beckett
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland, USA
| | - Jasmina S Redzic
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Denver, School of Medicine, Aurora, Colorado, USA
| | - Elan Eisenmesser
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Denver, School of Medicine, Aurora, Colorado, USA
| | - Cheyenne Palm
- Department of Biological Sciences, Towson University, Towson, Maryland, USA
| | - Katrina Schmidt
- Department of Biological Sciences, Towson University, Towson, Maryland, USA
| | - Alexis H Scudder
- Department of Biological Sciences, Towson University, Towson, Maryland, USA
| | - Trinity Obiorah
- Department of Biological Sciences, Towson University, Towson, Maryland, USA
| | - Kow Essuman
- Department of Developmental Biology, Washington University School of Medicine, St Louis, Missouri, USA; Department of Neurosurgery, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Jeffrey Milbrandt
- Department of Developmental Biology, Washington University School of Medicine, St Louis, Missouri, USA
| | - Aaron Diantonio
- Department of Developmental Biology, Washington University School of Medicine, St Louis, Missouri, USA
| | - Krishanu Ray
- Division of Vaccine Research, Institute of Human Virology, School of Medicine, University of Maryland, Baltimore, Maryland, USA; Department of Biochemistry and Molecular Biology at the University of Maryland, School of Medicine, Baltimore, Maryland, USA
| | | | - Daniel Deredge
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland, USA
| | - Greg A Snyder
- Division of Vaccine Research, Institute of Human Virology, School of Medicine, University of Maryland, Baltimore, Maryland, USA; Department of Microbiology and Immunology, School of Medicine, University of Maryland, Baltimore, Maryland, USA.
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15
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Montoro-Gámez C, Nolte H, Molinié T, Evangelista G, Tröder SE, Barth E, Popovic M, Trifunovic A, Zevnik B, Langer T, Rugarli EI. SARM1 deletion delays cerebellar but not spinal cord degeneration in an enhanced mouse model of SPG7 deficiency. Brain 2023; 146:4117-4131. [PMID: 37086482 DOI: 10.1093/brain/awad136] [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: 12/06/2022] [Revised: 03/16/2023] [Accepted: 04/10/2023] [Indexed: 04/24/2023] Open
Abstract
Hereditary spastic paraplegia is a neurological condition characterized by predominant axonal degeneration in long spinal tracts, leading to weakness and spasticity in the lower limbs. The nicotinamide adenine dinucleotide (NAD+)-consuming enzyme SARM1 has emerged as a key executioner of axonal degeneration upon nerve transection and in some neuropathies. An increase in the nicotinamide mononucleotide/NAD+ ratio activates SARM1, causing catastrophic NAD+ depletion and axonal degeneration. However, the role of SARM1 in the pathogenesis of hereditary spastic paraplegia has not been investigated. Here, we report an enhanced mouse model for hereditary spastic paraplegia caused by mutations in SPG7. The eSpg7 knockout mouse carries a deletion in both Spg7 and Afg3l1, a redundant homologue expressed in mice but not in humans. The eSpg7 knockout mice recapitulate the phenotypic features of human patients, showing progressive symptoms of spastic-ataxia and degeneration of axons in the spinal cord as well as the cerebellum. We show that the lack of SPG7 rewires the mitochondrial proteome in both tissues, leading to an early onset decrease in mito-ribosomal subunits and a remodelling of mitochondrial solute carriers and transporters. To interrogate mechanisms leading to axonal degeneration in this mouse model, we explored the involvement of SARM1. Deletion of SARM1 delays the appearance of ataxic signs, rescues mitochondrial swelling and axonal degeneration of cerebellar granule cells and dampens neuroinflammation in the cerebellum. The loss of SARM1 also prevents endoplasmic reticulum abnormalities in long spinal cord axons, but does not halt the degeneration of these axons. Our data thus reveal a neuron-specific interplay between SARM1 and mitochondrial dysfunction caused by lack of SPG7 in hereditary spastic paraplegia.
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Affiliation(s)
- Carolina Montoro-Gámez
- Institute for Genetics, University of Cologne, Cologne 50931, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne 50931, Germany
| | - Hendrik Nolte
- Max Planck Institute for Biology of Ageing, Cologne 50931, Germany
| | - Thibaut Molinié
- Institute for Genetics, University of Cologne, Cologne 50931, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne 50931, Germany
| | - Giovanna Evangelista
- Institute for Genetics, University of Cologne, Cologne 50931, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne 50931, Germany
| | - Simon E Tröder
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne 50931, Germany
- in vivo Research Facility, Medical Faculty and University Hospital Cologne, University of Cologne, Cologne 50931, Germany
| | - Esther Barth
- Institute for Genetics, University of Cologne, Cologne 50931, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne 50931, Germany
| | - Milica Popovic
- Institute for Genetics, University of Cologne, Cologne 50931, Germany
- Institute for Mitochondrial Diseases and Aging, Medical Faculty, University of Cologne, Cologne 50931, Germany
| | - Aleksandra Trifunovic
- Institute for Genetics, University of Cologne, Cologne 50931, Germany
- Institute for Mitochondrial Diseases and Aging, Medical Faculty, University of Cologne, Cologne 50931, Germany
- Center for Molecular Medicine (CMMC), University of Cologne, Cologne 50931, Germany
| | - Branko Zevnik
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne 50931, Germany
- in vivo Research Facility, Medical Faculty and University Hospital Cologne, University of Cologne, Cologne 50931, Germany
| | - Thomas Langer
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne 50931, Germany
- Max Planck Institute for Biology of Ageing, Cologne 50931, Germany
| | - Elena I Rugarli
- Institute for Genetics, University of Cologne, Cologne 50931, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne 50931, Germany
- Center for Molecular Medicine (CMMC), University of Cologne, Cologne 50931, Germany
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16
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McLaren M, Conners R, Isupov MN, Gil-Díez P, Gambelli L, Gold VAM, Walter A, Connell SR, Williams B, Daum B. CryoEM reveals that ribosomes in microsporidian spores are locked in a dimeric hibernating state. Nat Microbiol 2023; 8:1834-1845. [PMID: 37709902 PMCID: PMC10522483 DOI: 10.1038/s41564-023-01469-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 08/11/2023] [Indexed: 09/16/2023]
Abstract
Translational control is an essential process for the cell to adapt to varying physiological or environmental conditions. To survive adverse conditions such as low nutrient levels, translation can be shut down almost entirely by inhibiting ribosomal function. Here we investigated eukaryotic hibernating ribosomes from the microsporidian parasite Spraguea lophii in situ by a combination of electron cryo-tomography and single-particle electron cryo-microscopy. We show that microsporidian spores contain hibernating ribosomes that are locked in a dimeric (100S) state, which is formed by a unique dimerization mechanism involving the beak region. The ribosomes within the dimer are fully assembled, suggesting that they are ready to be activated once the host cell is invaded. This study provides structural evidence for dimerization acting as a mechanism for ribosomal hibernation in microsporidia, and therefore demonstrates that eukaryotes utilize this mechanism in translational control.
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Affiliation(s)
- Mathew McLaren
- Living Systems Institute, University of Exeter, Exeter, UK
- Department of Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, UK
| | - Rebecca Conners
- Living Systems Institute, University of Exeter, Exeter, UK
- Department of Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, UK
| | - Michail N Isupov
- Department of Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, UK
| | - Patricia Gil-Díez
- Living Systems Institute, University of Exeter, Exeter, UK
- Department of Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, UK
- Crop Science Centre, Cambridge University, Cambridge, UK
| | - Lavinia Gambelli
- Living Systems Institute, University of Exeter, Exeter, UK
- Department of Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, UK
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK
| | - Vicki A M Gold
- Living Systems Institute, University of Exeter, Exeter, UK
- Department of Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, UK
| | - Andreas Walter
- Center of Optical Technologies, Aalen University, Aalen, Germany
| | - Sean R Connell
- Structural Biology of Cellular Machines, IIS Biobizkaia, Barakaldo, Spain
| | - Bryony Williams
- Living Systems Institute, University of Exeter, Exeter, UK
- Department of Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, UK
| | - Bertram Daum
- Living Systems Institute, University of Exeter, Exeter, UK.
- Department of Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, UK.
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17
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Khazma T, Grossman A, Guez-Haddad J, Feng C, Dabas H, Sain R, Weitman M, Zalk R, Isupov MN, Hammarlund M, Hons M, Opatowsky Y. Structure-function analysis of ceTIR-1/hSARM1 explains the lack of Wallerian axonal degeneration in C. elegans. Cell Rep 2023; 42:113026. [PMID: 37635352 PMCID: PMC10675840 DOI: 10.1016/j.celrep.2023.113026] [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: 01/07/2023] [Revised: 06/05/2023] [Accepted: 08/09/2023] [Indexed: 08/29/2023] Open
Abstract
Wallerian axonal degeneration (WD) does not occur in the nematode C. elegans, in contrast to other model animals. However, WD depends on the NADase activity of SARM1, a protein that is also expressed in C. elegans (ceSARM/ceTIR-1). We hypothesized that differences in SARM between species might exist and account for the divergence in WD. We first show that expression of the human (h)SARM1, but not ceTIR-1, in C. elegans neurons is sufficient to confer axon degeneration after nerve injury. Next, we determined the cryoelectron microscopy structure of ceTIR-1 and found that, unlike hSARM1, which exists as an auto-inhibited ring octamer, ceTIR-1 forms a readily active 9-mer. Enzymatically, the NADase activity of ceTIR-1 is substantially weaker (10-fold higher Km) than that of hSARM1, and even when fully active, it falls short of consuming all cellular NAD+. Our experiments provide insight into the molecular mechanisms and evolution of SARM orthologs and WD across species.
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Affiliation(s)
- Tami Khazma
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Atira Grossman
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Julia Guez-Haddad
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Chengye Feng
- Departments of Neuroscience and Genetics, Yale School of Medicine, New Haven, CT, USA
| | - Hadas Dabas
- Departments of Neuroscience and Genetics, Yale School of Medicine, New Haven, CT, USA
| | - Radhika Sain
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Michal Weitman
- Department of Chemistry, Bar-Ilan University, Ramat Gan, Israel
| | - Ran Zalk
- Ilse Katz Institute for Nanoscale Science & Technology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Michail N Isupov
- Henry Wellcome Building for Biocatalysis, Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, UK
| | - Marc Hammarlund
- Departments of Neuroscience and Genetics, Yale School of Medicine, New Haven, CT, USA.
| | - Michael Hons
- European Molecular Biology Laboratory, Grenoble, France.
| | - Yarden Opatowsky
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel.
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18
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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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19
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Feng R, Zhang P. The significance of M1 macrophage should be highlighted in peripheral nerve regeneration. Histol Histopathol 2023; 38:975-987. [PMID: 36734334 DOI: 10.14670/hh-18-591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Macrophage influences peripheral nerve regeneration. According to the classical M1/M2 paradigm, the M1 macrophage is an inhibitor of regeneration, while the M2 macrophage is a promoter. However, several studies have shown that M1 macrophages are indispensable for peripheral nerve repair and facilitate many critical processes in axonal regeneration. In this review, we summarized the information on macrophage polarization and focused on the activities of M1 macrophages in regeneration. We also provided some examples where the macrophage phenotypes were regulated to help regeneration. We argued that the coordination of both macrophage phenotypes might be effective in peripheral nerve repair, and a more comprehensive view of macrophages might contribute to macrophage-based immunomodulatory therapies.
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Affiliation(s)
- Ruiqin Feng
- Department of Orthopedics and Trauma, Peking University People's Hospital, Key Laboratory of Trauma and Neural Regeneration, Ministry of Education and National Center for Trauma Medicine, Beijing, China
| | - Peixun Zhang
- Department of Orthopedics and Trauma, Peking University People's Hospital, Key Laboratory of Trauma and Neural Regeneration, Ministry of Education and National Center for Trauma Medicine, Beijing, China.
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20
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Locci F, Wang J, Parker JE. TIR-domain enzymatic activities at the heart of plant immunity. CURRENT OPINION IN PLANT BIOLOGY 2023; 74:102373. [PMID: 37150050 DOI: 10.1016/j.pbi.2023.102373] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 03/15/2023] [Accepted: 04/04/2023] [Indexed: 05/09/2023]
Abstract
Toll/interleukin-1/resistance (TIR) domain proteins contribute to innate immunity in all cellular kingdoms. TIR modules are activated by self-association and in plants, mammals and bacteria, some TIRs have enzymatic functions that are crucial for disease resistance and/or cell death. Many plant TIR-only proteins and pathogen effector-activated TIR-domain NLR receptors are NAD+ hydrolysing enzymes. Biochemical, structural and functional studies established that for both plant TIR-protein types, and certain bacterial TIRs, NADase activity generates bioactive signalling intermediates which promote resistance. A set of plant TIR-catalysed nucleotide isomers was discovered which bind to and activate EDS1 complexes, promoting their interactions with co-functioning helper NLRs. Analysis of TIR enzymes across kingdoms fills an important gap in understanding how pathogen disturbance induces TIR-regulated immune responses.
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Affiliation(s)
- Federica Locci
- Department of Plant-Microbe Interactions, Max-Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, Cologne, 50829, Germany
| | - Junli Wang
- Department of Plant-Microbe Interactions, Max-Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, Cologne, 50829, Germany
| | - Jane E Parker
- Department of Plant-Microbe Interactions, Max-Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, Cologne, 50829, Germany; Cologne-Düsseldorf Cluster of Excellence on Plant Sciences (CEPLAS), 40225, Düsseldorf, Germany.
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21
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Tribble JR, Hui F, Quintero H, El Hajji S, Bell K, Di Polo A, Williams PA. Neuroprotection in glaucoma: Mechanisms beyond intraocular pressure lowering. Mol Aspects Med 2023; 92:101193. [PMID: 37331129 DOI: 10.1016/j.mam.2023.101193] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/25/2023] [Accepted: 06/04/2023] [Indexed: 06/20/2023]
Abstract
Glaucoma is a common, complex, multifactorial neurodegenerative disease characterized by progressive dysfunction and then loss of retinal ganglion cells, the output neurons of the retina. Glaucoma is the most common cause of irreversible blindness and affects ∼80 million people worldwide with many more undiagnosed. The major risk factors for glaucoma are genetics, age, and elevated intraocular pressure. Current strategies only target intraocular pressure management and do not directly target the neurodegenerative processes occurring at the level of the retinal ganglion cell. Despite strategies to manage intraocular pressure, as many as 40% of glaucoma patients progress to blindness in at least one eye during their lifetime. As such, neuroprotective strategies that target the retinal ganglion cell and these neurodegenerative processes directly are of great therapeutic need. This review will cover the recent advances from basic biology to on-going clinical trials for neuroprotection in glaucoma covering degenerative mechanisms, metabolism, insulin signaling, mTOR, axon transport, apoptosis, autophagy, and neuroinflammation. With an increased understanding of both the basic and clinical mechanisms of the disease, we are closer than ever to a neuroprotective strategy for glaucoma.
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Affiliation(s)
- James R Tribble
- Department of Clinical Neuroscience, Division of Eye and Vision, St. Erik Eye Hospital, Karolinska Institutet, Stockholm, Sweden
| | - Flora Hui
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia; Department of Optometry & Vision Sciences, The University of Melbourne, Melbourne, Australia
| | - Heberto Quintero
- Department of Neuroscience, University of Montreal, Montreal, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Canada
| | - Sana El Hajji
- Department of Neuroscience, University of Montreal, Montreal, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Canada
| | - Katharina Bell
- NHMRC Clinical Trials Centre, University of Sydney, Australia; Eye ACP Duke-NUS, Singapore
| | - Adriana Di Polo
- Department of Neuroscience, University of Montreal, Montreal, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Canada
| | - Pete A Williams
- Department of Clinical Neuroscience, Division of Eye and Vision, St. Erik Eye Hospital, Karolinska Institutet, Stockholm, Sweden.
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22
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Clements CM, Henen MA, Vögeli B, Shellman YG. The Structural Dynamics, Complexity of Interactions, and Functions in Cancer of Multi-SAM Containing Proteins. Cancers (Basel) 2023; 15:3019. [PMID: 37296980 PMCID: PMC10252437 DOI: 10.3390/cancers15113019] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 05/25/2023] [Accepted: 05/30/2023] [Indexed: 06/12/2023] Open
Abstract
SAM domains are crucial mediators of diverse interactions, including those important for tumorigenesis or metastasis of cancers, and thus SAM domains can be attractive targets for developing cancer therapies. This review aims to explore the literature, especially on the recent findings of the structural dynamics, regulation, and functions of SAM domains in proteins containing more than one SAM (multi-SAM containing proteins, MSCPs). The topics here include how intrinsic disorder of some SAMs and an additional SAM domain in MSCPs increase the complexity of their interactions and oligomerization arrangements. Many similarities exist among these MSCPs, including their effects on cancer cell adhesion, migration, and metastasis. In addition, they are all involved in some types of receptor-mediated signaling and neurology-related functions or diseases, although the specific receptors and functions vary. This review also provides a simple outline of methods for studying protein domains, which may help non-structural biologists to reach out and build new collaborations to study their favorite protein domains/regions. Overall, this review aims to provide representative examples of various scenarios that may provide clues to better understand the roles of SAM domains and MSCPs in cancer in general.
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Affiliation(s)
- Christopher M. Clements
- Department of Dermatology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA;
| | - Morkos A. Henen
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; (M.A.H.); (B.V.)
| | - Beat Vögeli
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; (M.A.H.); (B.V.)
| | - Yiqun G. Shellman
- Department of Dermatology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA;
- Charles C. Gates Regenerative Medicine and Stem Cell Biology Institute, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
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23
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Fang J, Chen W, Hou P, Liu Z, Zuo M, Liu S, Feng C, Han Y, Li P, Shi Y, Shao C. NAD + metabolism-based immunoregulation and therapeutic potential. Cell Biosci 2023; 13:81. [PMID: 37165408 PMCID: PMC10171153 DOI: 10.1186/s13578-023-01031-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 04/14/2023] [Indexed: 05/12/2023] Open
Abstract
Nicotinamide adenine dinucleotide (NAD+) is a critical metabolite that acts as a cofactor in energy metabolism, and serves as a cosubstrate for non-redox NAD+-dependent enzymes, including sirtuins, CD38 and poly(ADP-ribose) polymerases. NAD+ metabolism can regulate functionality attributes of innate and adaptive immune cells and contribute to inflammatory responses. Thus, the manipulation of NAD+ bioavailability can reshape the courses of immunological diseases. Here, we review the basics of NAD+ biochemistry and its roles in the immune response, and discuss current challenges and the future translational potential of NAD+ research in the development of therapeutics for inflammatory diseases, such as COVID-19.
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Affiliation(s)
- Jiankai Fang
- Institutes for Translational Medicine, State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China
| | - Wangwang Chen
- Laboratory Animal Center, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China
| | - Pengbo Hou
- Institutes for Translational Medicine, State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China
- Department of Experimental Medicine and Biochemical Sciences, TOR, University of Rome Tor Vergata, Rome, Italy
| | - Zhanhong Liu
- Institutes for Translational Medicine, State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China
- Department of Experimental Medicine and Biochemical Sciences, TOR, University of Rome Tor Vergata, Rome, Italy
| | - Muqiu Zuo
- Institutes for Translational Medicine, State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China
| | - Shisong Liu
- Institutes for Translational Medicine, State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China
| | - Chao Feng
- Institutes for Translational Medicine, State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China
- Department of Experimental Medicine and Biochemical Sciences, TOR, University of Rome Tor Vergata, Rome, Italy
| | - Yuyi Han
- Institutes for Translational Medicine, State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China
- Department of Experimental Medicine and Biochemical Sciences, TOR, University of Rome Tor Vergata, Rome, Italy
| | - Peishan Li
- Institutes for Translational Medicine, State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China.
| | - Yufang Shi
- Institutes for Translational Medicine, State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China.
- Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.
| | - Changshun Shao
- Institutes for Translational Medicine, State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China.
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24
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Sarkar A, Dutta S, Sur M, Chakraborty S, Dey P, Mukherjee P. Early loss of endogenous NAD + following rotenone treatment leads to mitochondrial dysfunction and Sarm1 induction that is ameliorated by PARP inhibition. FEBS J 2023; 290:1596-1624. [PMID: 36239430 DOI: 10.1111/febs.16652] [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: 02/14/2022] [Revised: 08/17/2022] [Accepted: 10/13/2022] [Indexed: 11/07/2022]
Abstract
Sarm1 is an evolutionary conserved innate immune adaptor protein that has emerged as a primary regulator of programmed axonal degeneration over the past decade. In vitro structural insights have revealed that although Sarm1 induces energy depletion by breaking down nicotinamide adenine dinucleotide+ (NAD+ ), it is also allosterically inhibited by NAD+ . However, how NAD+ levels modulate the activation of intracellular Sarm1 has not been elucidated so far. This study focuses on understanding the events leading to Sarm1 activation in both neuronal and non-neuronal cells using the mitochondrial complex I inhibitor rotenone. Here, we report the regulation of rotenone-induced cell death by loss of NAD+ that may act as a 'biological trigger' of Sarm1 activation. Our study revealed that early loss of endogenous NAD+ levels arising due to PARP1 hyperactivation preceded Sarm1 induction following rotenone treatment. Interestingly, replenishing NAD+ levels by the PARP inhibitor, PJ34 restored mitochondrial complex I activity and also prevented subsequent Sarm1 activation in rotenone-treated cells. These cellular data were further validated in Drosophila melanogaster where a significant reduction in rotenone-mediated loss of locomotor abilities, and reduced dSarm expression was observed in the flies following PARP inhibition. Taken together, these observations not only uncover a novel regulation of Sarm1 induction by endogenous NAD+ levels but also point towards an important understanding on how PARP inhibitors could be repurposed in the treatment of mitochondrial complex I deficiency disorders.
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Affiliation(s)
- Ankita Sarkar
- Institute of Health Sciences, Presidency University, Kolkata, India
| | - Sourav Dutta
- Institute of Health Sciences, Presidency University, Kolkata, India
| | - Malinki Sur
- Institute of Health Sciences, Presidency University, Kolkata, India
| | | | - Puja Dey
- Institute of Health Sciences, Presidency University, Kolkata, India
| | - Piyali Mukherjee
- Institute of Health Sciences, Presidency University, Kolkata, India
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25
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Czech VL, O'Connor LC, Philippon B, Norman E, Byrne AB. TIR-1/SARM1 inhibits axon regeneration and promotes axon degeneration. eLife 2023; 12:80856. [PMID: 37083456 PMCID: PMC10121217 DOI: 10.7554/elife.80856] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 01/31/2023] [Indexed: 03/03/2023] Open
Abstract
Growth and destruction are central components of the neuronal injury response. Injured axons that are capable of repair, including axons in the mammalian peripheral nervous system and in many invertebrate animals, often regenerate and degenerate on either side of the injury. Here we show that TIR-1/dSarm/SARM1, a key regulator of axon degeneration, also inhibits regeneration of injured motor axons. The increased regeneration in tir-1 mutants is not a secondary consequence of its effects on degeneration, nor is it determined by the NADase activity of TIR-1. Rather, we found that TIR-1 functions cell-autonomously to regulate each of the seemingly opposite processes through distinct interactions with two MAP kinase pathways. On one side of the injury, TIR-1 inhibits axon regeneration by activating the NSY-1/ASK1 MAPK signaling cascade, while on the other side of the injury, TIR-1 simultaneously promotes axon degeneration by interacting with the DLK-1 mitogen-activated protein kinase (MAPK) signaling cascade. In parallel, we found that the ability to cell-intrinsically inhibit axon regeneration is conserved in human SARM1. Our finding that TIR-1/SARM1 regulates axon regeneration provides critical insight into how axons coordinate a multidimensional response to injury, consequently informing approaches to manipulate the response toward repair.
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Affiliation(s)
- Victoria L Czech
- Department of Neurobiology, UMass Chan Massachusetts Medical School
| | | | | | - Emily Norman
- Department of Neurobiology, UMass Chan Massachusetts Medical School
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26
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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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27
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Khazma T, Golan-Vaishenker Y, Guez-Haddad J, Grossman A, Sain R, Weitman M, Plotnikov A, Zalk R, Yaron A, Hons M, Opatowsky Y. A duplex structure of SARM1 octamers stabilized by a new inhibitor. Cell Mol Life Sci 2022; 80:16. [PMID: 36564647 PMCID: PMC11072711 DOI: 10.1007/s00018-022-04641-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 11/16/2022] [Accepted: 11/19/2022] [Indexed: 12/25/2022]
Abstract
In recent years, there has been growing interest in SARM1 as a potential breakthrough drug target for treating various pathologies of axon degeneration. SARM1-mediated axon degeneration relies on its TIR domain NADase activity, but recent structural data suggest that the non-catalytic ARM domain could also serve as a pharmacological site as it has an allosteric inhibitory function. Here, we screened for synthetic small molecules that inhibit SARM1, and tested a selected set of these compounds in a DRG axon degeneration assay. Using cryo-EM, we found that one of the newly discovered inhibitors, a calmidazolium designated TK106, not only stabilizes the previously reported inhibited conformation of the octamer, but also a meta-stable structure: a duplex of octamers (16 protomers), which we have now determined to 4.0 Å resolution. In the duplex, each ARM domain protomer is engaged in lateral interactions with neighboring protomers, and is further stabilized by contralateral contacts with the opposing octamer ring. Mutagenesis of the duplex contact sites leads to a moderate increase in SARM1 activation in cultured cells. Based on our data we propose that the duplex assembly constitutes an additional auto-inhibition mechanism that tightly prevents pre-mature activation and axon degeneration.
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Affiliation(s)
- Tami Khazma
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | | | - Julia Guez-Haddad
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Atira Grossman
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Radhika Sain
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Michal Weitman
- Department of Chemistry, Bar-Ilan University, Ramat Gan, Israel
| | - Alexander Plotnikov
- The Nancy and Stephen Grand Israel National Center for Personalized Medicine, Weizmann Institute of Science, Rehovot, Israel
| | - Ran Zalk
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
- Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Avraham Yaron
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Michael Hons
- European Molecular Biology Laboratory, Grenoble, France.
| | - Yarden Opatowsky
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel.
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28
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A conformation-specific nanobody targeting the nicotinamide mononucleotide-activated state of SARM1. Nat Commun 2022; 13:7898. [PMID: 36550129 PMCID: PMC9780360 DOI: 10.1038/s41467-022-35581-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 12/09/2022] [Indexed: 12/24/2022] Open
Abstract
Sterile alpha (SAM) and Toll/interleukin-1 receptor (TIR) motif containing 1 (SARM1) is an autoinhibitory NAD-consuming enzyme that is activated by the accumulation of nicotinamide mononucleotide (NMN) during axonal injury. Its activation mechanism is not fully understood. Here, we generate a nanobody, Nb-C6, that specifically recognizes NMN-activated SARM1. Nb-C6 stains only the activated SARM1 in cells stimulated with CZ-48, a permeant mimetic of NMN, and partially activates SARM1 in vitro and in cells. Cryo-EM of NMN/SARM1/Nb-C6 complex shows an octameric structure with ARM domains bending significantly inward and swinging out together with TIR domains. Nb-C6 binds to SAM domain of the activated SARM1 and stabilized its ARM domain. Mass spectrometry analyses indicate that the activated SARM1 in solution is highly dynamic and that the neighboring TIRs form transient dimers via the surface close to one BB loop. We show that Nb-C6 is a valuable tool for studies of SARM1 activation.
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29
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Bratkowski M, Burdett TC, Danao J, Wang X, Mathur P, Gu W, Beckstead JA, Talreja S, Yang YS, Danko G, Park JH, Walton M, Brown SP, Tegley CM, Joseph PRB, Reynolds CH, Sambashivan S. Uncompetitive, adduct-forming SARM1 inhibitors are neuroprotective in preclinical models of nerve injury and disease. Neuron 2022; 110:3711-3726.e16. [PMID: 36087583 DOI: 10.1016/j.neuron.2022.08.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 07/06/2022] [Accepted: 08/10/2022] [Indexed: 12/15/2022]
Abstract
Axon degeneration is an early pathological event in many neurological diseases. The identification of the nicotinamide adenine dinucleotide (NAD) hydrolase SARM1 as a central metabolic sensor and axon executioner presents an exciting opportunity to develop novel neuroprotective therapies that can prevent or halt the degenerative process, yet limited progress has been made on advancing efficacious inhibitors. We describe a class of NAD-dependent active-site SARM1 inhibitors that function by intercepting NAD hydrolysis and undergoing covalent conjugation with the reaction product adenosine diphosphate ribose (ADPR). The resulting small-molecule ADPR adducts are highly potent and confer compelling neuroprotection in preclinical models of neurological injury and disease, validating this mode of inhibition as a viable therapeutic strategy. Additionally, we show that the most potent inhibitor of CD38, a related NAD hydrolase, also functions by the same mechanism, further underscoring the broader applicability of this mechanism in developing therapies against this class of enzymes.
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Affiliation(s)
| | - Thomas C Burdett
- Biology Department, Nura Bio Inc., South San Francisco, CA 94080, USA
| | - Jean Danao
- Biology Department, Nura Bio Inc., South San Francisco, CA 94080, USA
| | - Xidao Wang
- Biology Department, Nura Bio Inc., South San Francisco, CA 94080, USA
| | - Prakhyat Mathur
- Biology Department, Nura Bio Inc., South San Francisco, CA 94080, USA
| | - Weijing Gu
- Biology Department, Nura Bio Inc., South San Francisco, CA 94080, USA
| | | | - Santosh Talreja
- Biology Department, Nura Bio Inc., South San Francisco, CA 94080, USA
| | - Yu-San Yang
- Biology Department, Nura Bio Inc., South San Francisco, CA 94080, USA
| | - Gregory Danko
- Biology Department, Nura Bio Inc., South San Francisco, CA 94080, USA
| | - Jae Hong Park
- Biology Department, Nura Bio Inc., South San Francisco, CA 94080, USA
| | - Mary Walton
- Chemistry Department, Nura Bio Inc., South San Francisco, CA 94080, USA
| | - Sean P Brown
- Chemistry Department, Nura Bio Inc., South San Francisco, CA 94080, USA
| | | | - Prem Raj B Joseph
- WuXi AppTec, Research Services Division, 6 Cedarbrook Drive, Cranbury, NJ 08512, USA
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30
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Lai MY, Li J, Zhang XX, Wu W, Li ZP, Sun ZX, Zhao MY, Yang DM, Wang DD, Li W, Zhao DM, Zhou XM, Yang LF. SARM1 participates in axonal degeneration and mitochondrial dysfunction in prion disease. Neural Regen Res 2022; 17:2293-2299. [PMID: 35259852 PMCID: PMC9083142 DOI: 10.4103/1673-5374.337051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Prion disease represents a group of fatal neurogenerative diseases in humans and animals that are associated with energy loss, axonal degeneration, and mitochondrial dysfunction. Axonal degeneration is an early hallmark of neurodegeneration and is triggered by SARM1. We found that depletion or dysfunctional mutation of SARM1 protected against NAD+ loss, axonal degeneration, and mitochondrial functional disorder induced by the neurotoxic peptide PrP106-126. NAD+ supplementation rescued prion-triggered axonal degeneration and mitochondrial dysfunction and SARM1 overexpression suppressed this protective effect. NAD+ supplementation in PrP106-126-incubated N2a cells, SARM1 depletion, and SARM1 dysfunctional mutation each blocked neuronal apoptosis and increased cell survival. Our results indicate that the axonal degeneration and mitochondrial dysfunction triggered by PrP106-126 are partially dependent on SARM1 NADase activity. This pathway has potential as a therapeutic target in the early stages of prion disease.
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Affiliation(s)
- Meng-Yu Lai
- National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Jie Li
- National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Xi-Xi Zhang
- National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Wei Wu
- National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Zhi-Ping Li
- National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Zhi-Xin Sun
- National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Meng-Yang Zhao
- National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Dong-Ming Yang
- National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Dong-Dong Wang
- National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Wen Li
- National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - De-Ming Zhao
- National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Xiang-Mei Zhou
- National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Li-Feng Yang
- National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China
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31
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Nizami HL, Minor KE, Chiao YA, Light CM, Lee CF. Sexually dimorphic effects of SARM1 deletion on cardiac NAD + metabolism and function. Am J Physiol Heart Circ Physiol 2022; 323:H774-H781. [PMID: 36053750 PMCID: PMC9529255 DOI: 10.1152/ajpheart.00370.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/17/2022] [Accepted: 08/24/2022] [Indexed: 11/22/2022]
Abstract
Nicotinamide adenine dinucleotide (NAD+) decline is repeatedly observed in heart disease and its risk factors. Although strategies promoting NAD+ synthesis to elevate NAD+ levels improve cardiac function, whether inhibition of NAD+ consumption can be therapeutic is less investigated. In this study, we examined the role of sterile-α and TIR motif containing 1 (SARM1) NAD+ hydrolase in mouse hearts, using global SARM1-knockout mice (KO). Cardiac function was assessed by echocardiography in male and female KO mice and wild-type (WT) controls. Hearts were collected for biochemical, histological, and molecular analyses. We found that the cardiac NAD+ pool was elevated in female KO mice, but only trended to increase in male KO mice. SARM1 deletion induced changes to a greater number of NAD+ metabolism transcripts in male mice than in female mice. Body weights, cardiac systolic and diastolic function, and geometry showed no changes in both male and female KO mice compared with WT counterparts. Male KO mice showed a small, but significant, elevation in cardiac collagen levels compared with WT counterparts, but no difference in collagen levels was detected in female mice. The increased collagen levels were associated with greater number of altered profibrotic and senescence-associated inflammatory genes in male KO mice, but not in female KO mice.NEW & NOTEWORTHY We examined the effects of SARM1 deletion on NAD+ pool, transcripts of NAD+ metabolism, and fibrotic pathway for the first time in mouse hearts. We observed the sexually dimorphic effects of SARM1 deletion. How these sex-dependent effects influence the outcomes of SARM1 deficiency in male and female mice in responses to cardiac stresses warrant further investigation. The elevation of cardiac NAD+ pool by SARM1 deletion provides evidence that targeting SARM1 may reverse disease-related NAD+ decline.
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Affiliation(s)
- Hina Lateef Nizami
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
| | - Keaton E Minor
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Ying Ann Chiao
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Christine M Light
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
| | - Chi Fung Lee
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
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32
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Hunting for Novel Routes in Anticancer Drug Discovery: Peptides against Sam-Sam Interactions. Int J Mol Sci 2022; 23:ijms231810397. [PMID: 36142306 PMCID: PMC9499636 DOI: 10.3390/ijms231810397] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/02/2022] [Accepted: 09/02/2022] [Indexed: 01/10/2023] Open
Abstract
Among the diverse protein binding modules, Sam (Sterile alpha motif) domains attract attention due to their versatility. They are present in different organisms and play many functions in physiological and pathological processes by binding multiple partners. The EphA2 receptor contains a Sam domain at the C-terminus (EphA2-Sam) that is able to engage protein regulators of receptor stability (including the lipid phosphatase Ship2 and the adaptor Odin). Ship2 and Odin are recruited by EphA2-Sam through heterotypic Sam-Sam interactions. Ship2 decreases EphA2 endocytosis and consequent degradation, producing chiefly pro-oncogenic outcomes in a cellular milieu. Odin, through its Sam domains, contributes to receptor stability by possibly interfering with ubiquitination. As EphA2 is upregulated in many types of tumors, peptide inhibitors of Sam-Sam interactions by hindering receptor stability could function as anticancer therapeutics. This review describes EphA2-Sam and its interactome from a structural and functional perspective. The diverse design strategies that have thus far been employed to obtain peptides targeting EphA2-mediated Sam-Sam interactions are summarized as well. The generated peptides represent good initial lead compounds, but surely many efforts need to be devoted in the close future to improve interaction affinities towards Sam domains and consequently validate their anticancer properties.
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Alexandris AS, Ryu J, Rajbhandari L, Harlan R, McKenney J, Wang Y, Aja S, Graham D, Venkatesan A, Koliatsos VE. Protective effects of NAMPT or MAPK inhibitors and NaR on Wallerian degeneration of mammalian axons. Neurobiol Dis 2022; 171:105808. [PMID: 35779777 PMCID: PMC10621467 DOI: 10.1016/j.nbd.2022.105808] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 06/14/2022] [Accepted: 06/25/2022] [Indexed: 01/23/2023] Open
Abstract
Wallerian degeneration (WD) is a conserved axonal self-destruction program implicated in several neurological diseases. WD is driven by the degradation of the NAD+ synthesizing enzyme NMNAT2, the buildup of its substrate NMN, and the activation of the NAD+ degrading SARM1, eventually leading to axonal fragmentation. The regulation and amenability of these events to therapeutic interventions remain unclear. Here we explored pharmacological strategies that modulate NMN and NAD+ metabolism, namely the inhibition of the NMN-synthesizing enzyme NAMPT, activation of the nicotinic acid riboside (NaR) salvage pathway and inhibition of the NMNAT2-degrading DLK MAPK pathway in an axotomy model in vitro. Results show that NAMPT and DLK inhibition cause a significant but time-dependent delay of WD. These time-dependent effects are related to NMNAT2 degradation and changes in NMN and NAD+ levels. Supplementation of NAMPT inhibition with NaR has an enhanced effect that does not depend on timing of intervention and leads to robust protection up to 4 days. Additional DLK inhibition extends this even further to 6 days. Metabolite analyses reveal complex effects indicating that NAMPT and MAPK inhibition act by reducing NMN levels, ameliorating NAD+ loss and suppressing SARM1 activity. Finally, the axonal NAD+/NMN ratio is highly predictive of cADPR levels, extending previous cell-free evidence on the allosteric regulation of SARM1. Our findings establish a window of axon protection extending several hours following injury. Moreover, we show prolonged protection by mixed treatments combining MAPK and NAMPT inhibition that proceed via complex effects on NAD+ metabolism and inhibition of SARM1.
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Affiliation(s)
| | - Jiwon Ryu
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Labchan Rajbhandari
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Robert Harlan
- The Molecular Determinants Center and Core, Johns Hopkins All Children's Hospital, St. Petersburg, FL, USA
| | - James McKenney
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Yiqing Wang
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Susan Aja
- The Molecular Determinants Center and Core, Johns Hopkins All Children's Hospital, St. Petersburg, FL, USA
| | - David Graham
- The Molecular Determinants Center and Core, Johns Hopkins All Children's Hospital, St. Petersburg, FL, USA
| | - Arun Venkatesan
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Vassilis E Koliatsos
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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Feldman HC, Merlini E, Guijas C, DeMeester KE, Njomen E, Kozina EM, Yokoyama M, Vinogradova E, Reardon HT, Melillo B, Schreiber SL, Loreto A, Blankman JL, Cravatt BF. Selective inhibitors of SARM1 targeting an allosteric cysteine in the autoregulatory ARM domain. Proc Natl Acad Sci U S A 2022; 119:e2208457119. [PMID: 35994671 PMCID: PMC9436332 DOI: 10.1073/pnas.2208457119] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 07/25/2022] [Indexed: 12/23/2022] Open
Abstract
The nicotinamide adenine dinucleotide hydrolase (NADase) sterile alpha toll/interleukin receptor motif containing-1 (SARM1) acts as a central executioner of programmed axon death and is a possible therapeutic target for neurodegenerative disorders. While orthosteric inhibitors of SARM1 have been described, this multidomain enzyme is also subject to intricate forms of autoregulation, suggesting the potential for allosteric modes of inhibition. Previous studies have identified multiple cysteine residues that support SARM1 activation and catalysis, but which of these cysteines, if any, might be selectively targetable by electrophilic small molecules remains unknown. Here, we describe the chemical proteomic discovery of a series of tryptoline acrylamides that site-specifically and stereoselectively modify cysteine-311 (C311) in the noncatalytic, autoregulatory armadillo repeat (ARM) domain of SARM1. These covalent compounds inhibit the NADase activity of WT-SARM1, but not C311A or C311S SARM1 mutants, show a high degree of proteome-wide selectivity for SARM1_C311 and stereoselectively block vincristine- and vacor-induced neurite degeneration in primary rodent dorsal root ganglion neurons. Our findings describe selective, covalent inhibitors of SARM1 targeting an allosteric cysteine, pointing to a potentially attractive therapeutic strategy for axon degeneration-dependent forms of neurological disease.
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Affiliation(s)
| | - Elisa Merlini
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge, CB2 0PY, United Kingdom
| | - Carlos Guijas
- Lundbeck La Jolla Research Center Inc, San Diego, CA 92121
| | | | - Evert Njomen
- Department of Chemistry, Scripps Research, La Jolla, CA 92037
| | - Ellen M Kozina
- Lundbeck La Jolla Research Center Inc, San Diego, CA 92121
| | - Minoru Yokoyama
- Department of Chemistry, Scripps Research, La Jolla, CA 92037
| | | | | | - Bruno Melillo
- Department of Chemistry, Scripps Research, La Jolla, CA 92037
- Chemical Biology and Therapeutics Science Program, Broad Institute, Cambridge, MA 02138
| | - Stuart L Schreiber
- Chemical Biology and Therapeutics Science Program, Broad Institute, Cambridge, MA 02138
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138
| | - Andrea Loreto
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge, CB2 0PY, United Kingdom
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Waller TJ, Collins CA. Multifaceted roles of SARM1 in axon degeneration and signaling. Front Cell Neurosci 2022; 16:958900. [PMID: 36090788 PMCID: PMC9453223 DOI: 10.3389/fncel.2022.958900] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 08/09/2022] [Indexed: 12/01/2022] Open
Abstract
Axons are considered to be particularly vulnerable components of the nervous system; impairments to a neuron’s axon leads to an effective silencing of a neuron’s ability to communicate with other cells. Nervous systems have therefore evolved plasticity mechanisms for adapting to axonal damage. These include acute mechanisms that promote the degeneration and clearance of damaged axons and, in some cases, the initiation of new axonal growth and synapse formation to rebuild lost connections. Here we review how these diverse processes are influenced by the therapeutically targetable enzyme SARM1. SARM1 catalyzes the breakdown of NAD+, which, when unmitigated, can lead to rundown of this essential metabolite and axonal degeneration. SARM1’s enzymatic activity also triggers the activation of downstream signaling pathways, which manifest numerous functions for SARM1 in development, innate immunity and responses to injury. Here we will consider the multiple intersections between SARM1 and the injury signaling pathways that coordinate cellular adaptations to nervous system damage.
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Affiliation(s)
- Thomas J. Waller
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
| | - Catherine A. Collins
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH, United States
- *Correspondence: Catherine A. Collins,
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36
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Ademi M, Yang X, Coleman MP, Gilley J. Natural variants of human SARM1 cause both intrinsic and dominant loss-of-function influencing axon survival. Sci Rep 2022; 12:13846. [PMID: 35974060 PMCID: PMC9381744 DOI: 10.1038/s41598-022-18052-8] [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: 06/09/2022] [Accepted: 08/04/2022] [Indexed: 11/08/2022] Open
Abstract
SARM1 is a central executioner of programmed axon death, and this role requires intrinsic NAD(P)ase or related enzyme activity. A complete absence of SARM1 robustly blocks axon degeneration in mice, but even a partial depletion confers meaningful protection. Since axon loss contributes substantially to the onset and progression of multiple neurodegenerative disorders, lower inherent SARM1 activity is expected to reduce disease susceptibility in some situations. We, therefore, investigated whether there are naturally occurring SARM1 alleles within the human population that encode SARM1 variants with loss-of-function. Out of the 18 natural SARM1 coding variants we selected as candidates, we found that 10 display loss-of-function in three complimentary assays: they fail to robustly deplete NAD in transfected HEK 293T cells; they lack constitutive and NMN-induced NADase activity; and they fail to promote axon degeneration in primary neuronal cultures. Two of these variants are also able to block axon degeneration in primary culture neurons in the presence of endogenous, wild-type SARM1, indicative of dominant loss-of-function. These results demonstrate that SARM1 loss-of-function variants occur naturally in the human population, and we propose that carriers of these alleles will have different degrees of reduced susceptibility to various neurological conditions.
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Affiliation(s)
- Mirlinda Ademi
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, University of Cambridge, Forvie Site, Robinson Way, Cambridge, CB2 0PY, UK
| | - Xiuna Yang
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, University of Cambridge, Forvie Site, Robinson Way, Cambridge, CB2 0PY, UK
| | - Michael P Coleman
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, University of Cambridge, Forvie Site, Robinson Way, Cambridge, CB2 0PY, UK.
| | - Jonathan Gilley
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, University of Cambridge, Forvie Site, Robinson Way, Cambridge, CB2 0PY, UK.
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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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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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Icso JD, Thompson PR. The chemical biology of NAD + regulation in axon degeneration. Curr Opin Chem Biol 2022; 69:102176. [PMID: 35780654 PMCID: PMC10084848 DOI: 10.1016/j.cbpa.2022.102176] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 05/24/2022] [Accepted: 05/27/2022] [Indexed: 11/26/2022]
Abstract
During axon degeneration, NAD+ levels are largely controlled by two enzymes: nicotinamide mononucleotide adenylyltransferase 2 (NMNAT2) and sterile alpha and toll interleukin motif containing protein 1 (SARM1). NMNAT2, which catalyzes the formation of NAD+ from NMN and ATP, is actively degraded leading to decreased NAD+ levels. SARM1 activity further decreases the concentration of NAD+ by catalyzing its hydrolysis to form nicotinamide and a mixture of ADPR and cADPR. Notably, SARM1 knockout mice show decreased neurodegeneration in animal models of axon degeneration, highlighting the therapeutic potential of targeting this novel NAD+ hydrolase. This review discusses recent advances in the SARM1 field, including SARM1 structure, regulation, and catalysis as well as the identification of the first SARM1 inhibitors.
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Affiliation(s)
- Janneke D Icso
- Program in Chemical Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA; Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Paul R Thompson
- Program in Chemical Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA; Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, MA, USA.
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40
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Herrmann KA, Liu Y, Llobet-Rosell A, McLaughlin CN, Neukomm LJ, Coutinho-Budd JC, Broihier HT. Divergent signaling requirements of dSARM in injury-induced degeneration and developmental glial phagocytosis. PLoS Genet 2022; 18:e1010257. [PMID: 35737721 PMCID: PMC9223396 DOI: 10.1371/journal.pgen.1010257] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 05/13/2022] [Indexed: 02/06/2023] Open
Abstract
Elucidating signal transduction mechanisms of innate immune pathways is essential to defining how they elicit distinct cellular responses. Toll-like receptors (TLR) signal through their cytoplasmic TIR domains which bind other TIR domain-containing adaptors. dSARM/SARM1 is one such TIR domain adaptor best known for its role as the central axon degeneration trigger after injury. In degeneration, SARM1's domains have been assigned unique functions: the ARM domain is auto-inhibitory, SAM-SAM domain interactions mediate multimerization, and the TIR domain has intrinsic NAD+ hydrolase activity that precipitates axonal demise. Whether and how these distinct functions contribute to TLR signaling is unknown. Here we show divergent signaling requirements for dSARM in injury-induced axon degeneration and TLR-mediated developmental glial phagocytosis through analysis of new knock-in domain and point mutations. We demonstrate intragenic complementation between reciprocal pairs of domain mutants during development, providing evidence for separability of dSARM functional domains in TLR signaling. Surprisingly, dSARM's NAD+ hydrolase activity is strictly required for both degenerative and developmental signaling, demonstrating that TLR signal transduction requires dSARM's enzymatic activity. In contrast, while SAM domain-mediated dSARM multimerization is important for axon degeneration, it is dispensable for TLR signaling. Finally, dSARM functions in a linear genetic pathway with the MAP3K Ask1 during development but not in degenerating axons. Thus, we propose that dSARM exists in distinct signaling states in developmental and pathological contexts.
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Affiliation(s)
- Kelsey A. Herrmann
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
| | - Yizhou Liu
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
| | - Arnau Llobet-Rosell
- Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland
| | - Colleen N. McLaughlin
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
| | - Lukas J. Neukomm
- Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland
| | - Jaeda C. Coutinho-Budd
- Department of Neuroscience, University of Virginia, Charlottesville, Virginia, United States of America
| | - Heather T. Broihier
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
- * E-mail:
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Brace EJ, Essuman K, Mao X, Palucki J, Sasaki Y, Milbrandt J, DiAntonio A. Distinct developmental and degenerative functions of SARM1 require NAD+ hydrolase activity. PLoS Genet 2022; 18:e1010246. [PMID: 35737728 PMCID: PMC9223315 DOI: 10.1371/journal.pgen.1010246] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 05/10/2022] [Indexed: 11/25/2022] Open
Abstract
SARM1 is the founding member of the TIR-domain family of NAD+ hydrolases and the central executioner of pathological axon degeneration. SARM1-dependent degeneration requires NAD+ hydrolysis. Prior to the discovery that SARM1 is an enzyme, SARM1 was studied as a TIR-domain adaptor protein with non-degenerative signaling roles in innate immunity and invertebrate neurodevelopment, including at the Drosophila neuromuscular junction (NMJ). Here we explore whether the NADase activity of SARM1 also contributes to developmental signaling. We developed transgenic Drosophila lines that express SARM1 variants with normal, deficient, and enhanced NADase activity and tested their function in NMJ development. We find that NMJ overgrowth scales with the amount of NADase activity, suggesting an instructive role for NAD+ hydrolysis in this developmental signaling pathway. While degenerative and developmental SARM1 signaling share a requirement for NAD+ hydrolysis, we demonstrate that these signals use distinct upstream and downstream mechanisms. These results identify SARM1-dependent NAD+ hydrolysis as a heretofore unappreciated component of developmental signaling. SARM1 now joins sirtuins and Parps as enzymes that regulate signal transduction pathways via mechanisms that involve NAD+ cleavage, greatly expanding the potential scope of SARM1 TIR NADase functions. SARM1 is the central executioner of axon loss, and inhibition of SARM1 is a therapeutic target for many devastating neurodegenerative disorders. SARM1 is the founding member of the TIR-domain family of NAD+ cleaving enzymes, destroying the essential metabolite NAD+ and inducing an energetic crisis in the axon. This was a surprising finding, as previously studied TIR-domain proteins were characterized as scaffolds that bind signaling proteins to coordinate signal transduction cascades. Indeed, before the discovery of the role of SARM1 in axon degeneration, SARM1 was studied as a regulator of intracellular signaling in immunity and neurodevelopment where it was assumed to act as a scaffold. Here we investigate whether the recently described SARM1 enzymatic activity also regulates such signal transduction pathways. Indeed, we show that a developmental signaling pathway scales with the amount of NADase activity, suggesting an instructive role for NAD+ cleavage. While degenerative and developmental SARM1 signaling share a requirement for NAD+ cleavage, they utilize distinct upstream and downstream mechanisms. With these findings, SARM1 now joins sirtuins and Parps as enzymes that regulate signal transduction pathways via mechanisms that involve NAD+ cleavage, greatly expanding the potential scope of SARM1 TIR NADase functions.
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Affiliation(s)
- E J Brace
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Kow Essuman
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Xianrong Mao
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - John Palucki
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Yo Sasaki
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Jeff Milbrandt
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, United States of America.,Needleman Center for Neurometabolism and Axonal Therapeutics, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Aaron DiAntonio
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America.,Needleman Center for Neurometabolism and Axonal Therapeutics, Washington University School of Medicine, St. Louis, Missouri, United States of America
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Chakraborty A, Minor KE, Nizami HL, Chiao YA, Lee CF. Harnessing NAD + Metabolism as Therapy for Cardiometabolic Diseases. Curr Heart Fail Rep 2022; 19:157-169. [PMID: 35556214 PMCID: PMC9339518 DOI: 10.1007/s11897-022-00550-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/15/2022] [Indexed: 01/10/2023]
Abstract
PURPOSE OF THE REVIEW This review summarizes current understanding on the roles of nicotinamide adenine dinucleotide (NAD+) metabolism in the pathogeneses and treatment development of metabolic and cardiac diseases. RECENT FINDINGS NAD+ was identified as a redox cofactor in metabolism and a co-substrate for a wide range of NAD+-dependent enzymes. NAD+ redox imbalance and depletion are associated with many pathologies where metabolism plays a key role, for example cardiometabolic diseases. This review is to delineate the current knowledge about harnessing NAD+ metabolism as potential therapy for cardiometabolic diseases. The review has summarized how NAD+ redox imbalance and depletion contribute to the pathogeneses of cardiometabolic diseases. Therapeutic evidence involving activation of NAD+ synthesis in pre-clinical and clinical studies was discussed. While activation of NAD+ synthesis shows great promise for therapy, the field of NAD+ metabolism is rapidly evolving. Therefore, it is expected that new mechanisms will be discovered as therapeutic targets for cardiometabolic diseases.
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Affiliation(s)
- Akash Chakraborty
- Cardiovascular Biology Research Program, MS 45, Oklahoma Medical Research Foundation, 825 NE 13th Street, Oklahoma City, OK, 73104, USA
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Keaton E Minor
- Cardiovascular Biology Research Program, MS 45, Oklahoma Medical Research Foundation, 825 NE 13th Street, Oklahoma City, OK, 73104, USA
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Hina Lateef Nizami
- Cardiovascular Biology Research Program, MS 45, Oklahoma Medical Research Foundation, 825 NE 13th Street, Oklahoma City, OK, 73104, USA
| | - Ying Ann Chiao
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Chi Fung Lee
- Cardiovascular Biology Research Program, MS 45, Oklahoma Medical Research Foundation, 825 NE 13th Street, Oklahoma City, OK, 73104, USA.
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
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43
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Beirowski B. Emerging evidence for compromised axonal bioenergetics and axoglial metabolic coupling as drivers of neurodegeneration. Neurobiol Dis 2022; 170:105751. [PMID: 35569720 DOI: 10.1016/j.nbd.2022.105751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 04/20/2022] [Accepted: 05/09/2022] [Indexed: 10/18/2022] Open
Abstract
Impaired bioenergetic capacity of the nervous system is thought to contribute to the pathogenesis of many neurodegenerative diseases (NDD). Since neuronal synapses are believed to be the major energy consumers in the nervous system, synaptic derangements resulting from energy deficits have been suggested to play a central role for the development of many of these disorders. However, long axons constitute the largest compartment of the neuronal network, require large amounts of energy, are metabolically and structurally highly vulnerable, and undergo early injurious stresses in many NDD. These stresses likely impose additional energy demands for continuous adaptations and repair processes, and may eventually overwhelm axonal maintenance mechanisms. Indeed, pathological axon degeneration (pAxD) is now recognized as an etiological focus in a wide array of NDD associated with bioenergetic abnormalities. In this paper I first discuss the recognition that a simple experimental model for pAxD is regulated by an auto-destruction program that exhausts distressed axons energetically. Provision of the energy substrate pyruvate robustly counteracts this axonal breakdown. Importantly, energy decline in axons is not only a consequence but also an initiator of this program. This opens the intriguing possibility that axon dysfunction and pAxD can be suppressed by preemptively energizing distressed axons. Second, I focus on the emerging concept that axons communicate energetically with their flanking glia. This axoglial metabolic coupling can help offset the axonal energy decline that activates the pAxD program but also jeopardize axon integrity as a result of perturbed glial metabolism. Third, I present compelling evidence that abnormal axonal energetics and compromised axoglial metabolic coupling accompany the activation of the pAxD auto-destruction pathway in models of glaucoma, a widespread neurodegenerative condition with pathogenic overlap to other common NDD. In conclusion, I propose a novel conceptual framework suggesting that therapeutic interventions focused on bioenergetic support of the nervous system should also address axons and their metabolic interactions with glia.
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Affiliation(s)
- Bogdan Beirowski
- Institute for Myelin and Glia Exploration, New York State Center of Excellence in Bioinformatics & Life Sciences (CBLS), University at Buffalo, Buffalo, NY 14203, USA; Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14214, USA.
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44
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Shi Y, Kerry PS, Nanson JD, Bosanac T, Sasaki Y, Krauss R, Saikot FK, Adams SE, Mosaiab T, Masic V, Mao X, Rose F, Vasquez E, Furrer M, Cunnea K, Brearley A, Gu W, Luo Z, Brillault L, Landsberg MJ, DiAntonio A, Kobe B, Milbrandt J, Hughes RO, Ve T. Structural basis of SARM1 activation, substrate recognition, and inhibition by small molecules. Mol Cell 2022; 82:1643-1659.e10. [PMID: 35334231 PMCID: PMC9188649 DOI: 10.1016/j.molcel.2022.03.007] [Citation(s) in RCA: 54] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 01/11/2022] [Accepted: 03/01/2022] [Indexed: 01/04/2023]
Abstract
The NADase SARM1 (sterile alpha and TIR motif containing 1) is a key executioner of axon degeneration and a therapeutic target for several neurodegenerative conditions. We show that a potent SARM1 inhibitor undergoes base exchange with the nicotinamide moiety of nicotinamide adenine dinucleotide (NAD+) to produce the bona fide inhibitor 1AD. We report structures of SARM1 in complex with 1AD, NAD+ mimetics and the allosteric activator nicotinamide mononucleotide (NMN). NMN binding triggers reorientation of the armadillo repeat (ARM) domains, which disrupts ARM:TIR interactions and leads to formation of a two-stranded TIR domain assembly. The active site spans two molecules in these assemblies, explaining the requirement of TIR domain self-association for NADase activity and axon degeneration. Our results reveal the mechanisms of SARM1 activation and substrate binding, providing rational avenues for the design of new therapeutics targeting SARM1.
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Affiliation(s)
- Yun Shi
- Institute for Glycomics, Griffith University, Southport, QLD 4222, Australia
| | - Philip S Kerry
- Evotec (UK) Ltd., 114 Innovation Drive, Milton Park, Abingdon, Oxfordshire OX14 4RZ, UK
| | - Jeffrey D Nanson
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, QLD 4072, Australia
| | - Todd Bosanac
- Disarm Therapeutics, a wholly-owned subsidiary of Eli Lilly & Co., Cambridge, MA, USA
| | - Yo Sasaki
- Needleman Center for Neurometabolism and Axonal Therapeutics and Department of Genetics, Washington University School of Medicine in Saint Louis, St. Louis, MO, USA
| | - Raul Krauss
- Disarm Therapeutics, a wholly-owned subsidiary of Eli Lilly & Co., Cambridge, MA, USA
| | - Forhad K Saikot
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, QLD 4072, Australia
| | - Sarah E Adams
- Evotec (UK) Ltd., 114 Innovation Drive, Milton Park, Abingdon, Oxfordshire OX14 4RZ, UK
| | - Tamim Mosaiab
- Institute for Glycomics, Griffith University, Southport, QLD 4222, Australia
| | - Veronika Masic
- Institute for Glycomics, Griffith University, Southport, QLD 4222, Australia
| | - Xianrong Mao
- Needleman Center for Neurometabolism and Axonal Therapeutics and Department of Genetics, Washington University School of Medicine in Saint Louis, St. Louis, MO, USA
| | - Faith Rose
- Institute for Glycomics, Griffith University, Southport, QLD 4222, Australia
| | - Eduardo Vasquez
- Institute for Glycomics, Griffith University, Southport, QLD 4222, Australia
| | - Marieke Furrer
- Evotec SE, Manfred Eigen Campus, Essener Bogen 7, 22419 Hamburg, Germany
| | - Katie Cunnea
- Evotec (UK) Ltd., 114 Innovation Drive, Milton Park, Abingdon, Oxfordshire OX14 4RZ, UK
| | - Andrew Brearley
- Evotec (UK) Ltd., 114 Innovation Drive, Milton Park, Abingdon, Oxfordshire OX14 4RZ, UK
| | - Weixi Gu
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, QLD 4072, Australia
| | - Zhenyao Luo
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, QLD 4072, Australia
| | - Lou Brillault
- Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, Australia
| | - Michael J Landsberg
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, QLD 4072, Australia
| | - Aaron DiAntonio
- Needleman Center for Neurometabolism and Axonal Therapeutics and Department of Developmental Biology, Washington University School of Medicine in Saint Louis, St. Louis, MO, USA
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, QLD 4072, Australia
| | - Jeffrey Milbrandt
- Needleman Center for Neurometabolism and Axonal Therapeutics and Department of Genetics, Washington University School of Medicine in Saint Louis, St. Louis, MO, USA
| | - Robert O Hughes
- Disarm Therapeutics, a wholly-owned subsidiary of Eli Lilly & Co., Cambridge, MA, USA.
| | - Thomas Ve
- Institute for Glycomics, Griffith University, Southport, QLD 4222, Australia.
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45
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Lapin D, Johanndrees O, Wu Z, Li X, Parker JE. Molecular innovations in plant TIR-based immunity signaling. THE PLANT CELL 2022; 34:1479-1496. [PMID: 35143666 PMCID: PMC9153377 DOI: 10.1093/plcell/koac035] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 01/27/2022] [Indexed: 05/19/2023]
Abstract
A protein domain (Toll and Interleukin-1 receptor [TIR]-like) with homology to animal TIRs mediates immune signaling in prokaryotes and eukaryotes. Here, we present an overview of TIR evolution and the molecular versatility of TIR domains in different protein architectures for host protection against microbial attack. Plant TIR-based signaling emerges as being central to the potentiation and effectiveness of host defenses triggered by intracellular and cell-surface immune receptors. Equally relevant for plant fitness are mechanisms that limit potent TIR signaling in healthy tissues but maintain preparedness for infection. We propose that seed plants evolved a specialized protein module to selectively translate TIR enzymatic activities to defense outputs, overlaying a more general function of TIRs.
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Affiliation(s)
- Dmitry Lapin
- Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, Cologne 50829, Germany
- Plant-Microbe Interactions, Department of Biology, Utrecht University, Utrecht 3584 CH, The Netherlands
- Author for correspondence: (D.L.), (J.E.P.)
| | - Oliver Johanndrees
- Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, Cologne 50829, Germany
| | - Zhongshou Wu
- Michael Smith Labs and Department of Botany, University of British Columbia, Vancouver BC V6T 1Z4, Canada
| | - Xin Li
- Michael Smith Labs and Department of Botany, University of British Columbia, Vancouver BC V6T 1Z4, Canada
| | - Jane E Parker
- Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, Cologne 50829, Germany
- Cluster of Excellence on Plant Sciences (CEPLAS), Duesseldorf 40225, Germany
- Author for correspondence: (D.L.), (J.E.P.)
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46
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Cao Y, Wang Y, Yang J. NAD +-dependent mechanism of pathological axon degeneration. CELL INSIGHT 2022; 1:100019. [PMID: 37193131 PMCID: PMC10120281 DOI: 10.1016/j.cellin.2022.100019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 03/01/2022] [Accepted: 03/02/2022] [Indexed: 05/18/2023]
Abstract
Pathological axon degeneration is broadly observed in neurodegenerative diseases. This unique process of axonal pathology could directly interfere with the normal functions of neurocircuitries and contribute to the onset of clinical symptoms in patients. It has been increasingly recognized that functional preservation of axonal structures is an indispensable part of therapeutic strategies for treating neurological disorders. In the past decades, the research field has witnessed significant breakthroughs in understanding the stereotyped self-destruction of axons upon neurodegenerative insults, which is distinct from all the known types of programmed cell death. In particular, the novel NAD+-dependent mechanism involving the WLDs, NMNAT2, and SARM1 proteins has emerged. This review summarizes the landmark discoveries elucidating the molecular pathway of pathological axon degeneration and highlights the evolving concept that neurodegeneration would be intrinsically linked to NAD+ and energy metabolism.
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Affiliation(s)
- Ying Cao
- Center for Life Sciences, Peking University, Beijing, 100871, China
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China
| | - Yi Wang
- Center for Life Sciences, Peking University, Beijing, 100871, China
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China
| | - Jing Yang
- Center for Life Sciences, Peking University, Beijing, 100871, China
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing, 100871, China
- IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
- Chinese Institute for Brain Research, Beijing, 102206, China
- Institute of Molecular Physiology, Shenzhen Bay Laboratory, Shenzhen, 518055, China
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47
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Lu Q, Botchway BOA, Zhang Y, Jin T, Liu X. SARM1 can be a potential therapeutic target for spinal cord injury. Cell Mol Life Sci 2022; 79:161. [PMID: 35224705 PMCID: PMC11072485 DOI: 10.1007/s00018-022-04195-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 01/26/2022] [Accepted: 02/05/2022] [Indexed: 01/03/2023]
Abstract
Injury to the spinal cord is devastating. Studies have implicated Wallerian degeneration as the main cause of axonal destruction in the wake of spinal cord injury. Therefore, the suppression of Wallerian degeneration could be beneficial for spinal cord injury treatment. Sterile alpha and armadillo motif-containing protein 1 (SARM1) is a key modulator of Wallerian degeneration, and its impediment can improve spinal cord injury to a significant degree. In this report, we analyze the various signaling domains of SARM1, the recent findings on Wallerian degeneration and its relation to axonal insults, as well as its connection to SARM1, the mitogen-activated protein kinase (MAPK) signaling, and the survival factor, nicotinamide mononucleotide adenylyltransferase 2 (NMNAT2). We then elaborate on the possible role of SARM1 in spinal cord injury and explicate how its obstruction could potentially alleviate the injury.
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Affiliation(s)
- Qicheng Lu
- Department of Histology and Embryology, Medical College, Shaoxing University, Shaoxing, China
| | - Benson O A Botchway
- Institute of Neuroscience, Zhejiang University School of Medicine, Hangzhou, China
| | - Yong Zhang
- Department of Histology and Embryology, Medical College, Shaoxing University, Shaoxing, China
| | - Tian Jin
- Department of Histology and Embryology, Medical College, Shaoxing University, Shaoxing, China
| | - Xuehong Liu
- Department of Histology and Embryology, Medical College, Shaoxing University, Shaoxing, China.
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48
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Zhuang J, Xie L, Zheng L. A Glimpse of Programmed Cell Death Among Bacteria, Animals, and Plants. Front Cell Dev Biol 2022; 9:790117. [PMID: 35223864 PMCID: PMC8866957 DOI: 10.3389/fcell.2021.790117] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 11/24/2021] [Indexed: 12/15/2022] Open
Abstract
Programmed cell death (PCD) in animals mainly refers to lytic and non-lytic forms. Disruption and integrity of the plasma membrane are considered as hallmarks of lytic and apoptotic cell death, respectively. These lytic cell death programs can prevent the hosts from microbial pathogens. The key to our understanding of these cases is pattern recognition receptors, such as TLRs in animals and LRR-RLKs in plants, and nod-like receptors (NLRs). Herein, we emphatically discuss the biochemical and structural studies that have clarified the anti-apoptotic and pro-apoptotic functions of Bcl-2 family proteins during intrinsic apoptosis and how caspase-8 among apoptosis, necroptosis, and pyroptosis sets the switchable threshold and integrates innate immune signaling, and that have compared the similarity and distinctness of the apoptosome, necroptosome, and inflammasome. We recapitulate that the necroptotic MLKL pore, pyroptotic gasdermin pore, HR-inducing resistosome, and mitochondrial Bcl-2 family all can form ion channels, which all directly boost membrane disruption. Comparing the conservation and unique aspects of PCD including ferrroptosis among bacteria, animals, and plants, the commonly shared immune domains including TIR-like, gasdermin-like, caspase-like, and MLKL/CC-like domains act as arsenal modules to restructure the diverse architecture to commit PCD suicide upon stresses/stimuli for host community.
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Affiliation(s)
- Jun Zhuang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou, China
- Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, China
- *Correspondence: Jun Zhuang,
| | - Li Xie
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou, China
- Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Luping Zheng
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou, China
- Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, China
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49
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Angeletti C, Amici A, Gilley J, Loreto A, Trapanotto AG, Antoniou C, Merlini E, Coleman MP, Orsomando G. SARM1 is a multi-functional NAD(P)ase with prominent base exchange activity, all regulated bymultiple physiologically relevant NAD metabolites. iScience 2022; 25:103812. [PMID: 35198877 PMCID: PMC8844822 DOI: 10.1016/j.isci.2022.103812] [Citation(s) in RCA: 46] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 12/13/2021] [Accepted: 01/20/2022] [Indexed: 12/11/2022] Open
Abstract
SARM1 is an NAD(P) glycohydrolase and TLR adapter with an essential, prodegenerative role in programmed axon death (Wallerian degeneration). Like other NAD(P)ases, it catalyzes multiple reactions that need to be fully investigated. Here, we compare these multiple activities for recombinant human SARM1, human CD38, and Aplysia californica ADP ribosyl cyclase. SARM1 has the highest transglycosidation (base exchange) activity at neutral pH and with some bases this dominates NAD(P) hydrolysis and cyclization. All SARM1 activities, including base exchange at neutral pH, are activated by an increased NMN:NAD ratio, at physiological levels of both metabolites. SARM1 base exchange occurs also in DRG neurons and is thus a very likely physiological source of calcium-mobilizing agent NaADP. Finally, we identify regulation by free pyridines, NADP, and nicotinic acid riboside (NaR) on SARM1, all of therapeutic interest. Understanding which specific SARM1 function(s) is responsible for axon degeneration is essential for its targeting in disease. Base exchange is a prominent, and sometimes completely dominant, SARM1 activity Physiologically relevant NMN:NAD ratios may regulate all of SARM1's multiple activities Physiological NADP may inhibit SARM1 more potently than NAD and via a distinct site NaR and VR both selectively inhibit SARM1 and are thus possible effectors or drug leads
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50
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Ji H, Sapar ML, Sarkar A, Wang B, Han C. Phagocytosis and self-destruction break down dendrites of Drosophila sensory neurons at distinct steps of Wallerian degeneration. Proc Natl Acad Sci U S A 2022; 119:e2111818119. [PMID: 35058357 PMCID: PMC8795528 DOI: 10.1073/pnas.2111818119] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 12/01/2021] [Indexed: 12/12/2022] Open
Abstract
After injury, severed dendrites and axons expose the "eat-me" signal phosphatidylserine (PS) on their surface while they break down. The degeneration of injured axons is controlled by a conserved Wallerian degeneration (WD) pathway, which is thought to activate neurite self-destruction through Sarm-mediated nicotinamide adenine dinucleotide (NAD+) depletion. While neurite PS exposure is known to be affected by genetic manipulations of NAD+, how the WD pathway coordinates both neurite PS exposure and self-destruction and whether PS-induced phagocytosis contributes to neurite breakdown in vivo remain unknown. Here, we show that in Drosophila sensory dendrites, PS exposure and self-destruction are two sequential steps of WD resulting from Sarm activation. Surprisingly, phagocytosis is the main driver of dendrite degeneration induced by both genetic NAD+ disruptions and injury. However, unlike neuronal Nmnat loss, which triggers PS exposure only and results in phagocytosis-dependent dendrite degeneration, injury activates both PS exposure and self-destruction as two redundant means of dendrite degeneration. Furthermore, the axon-death factor Axed is only partially required for self-destruction of injured dendrites, acting in parallel with PS-induced phagocytosis. Lastly, injured dendrites exhibit a unique rhythmic calcium-flashing that correlates with WD. Therefore, both NAD+-related general mechanisms and dendrite-specific programs govern PS exposure and self-destruction in injury-induced dendrite degeneration in vivo.
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Affiliation(s)
- Hui Ji
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853
| | - Maria L Sapar
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853
| | - Ankita Sarkar
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853
| | - Bei Wang
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853
| | - Chun Han
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853;
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853
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