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Pokharel PV, Newchurch AM, Overby SC, Spease CA, Darzi LG, Kraemer BR. LM11a-31 Inhibits p75 Neurotrophin Receptor (p75 NTR ) Cleavage and is Neuroprotective in a Cell Culture Model of Parkinson's Disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.09.10.612299. [PMID: 39314373 PMCID: PMC11419115 DOI: 10.1101/2024.09.10.612299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/25/2024]
Abstract
The p75 Neurotrophin Receptor (p75 NTR ) is a multifunctional transmembrane protein that mediates neuronal responses to pathological conditions in specific regions of the nervous system. In many biological contexts, p75 NTR signaling is initiated through sequential cleavage of the receptor by α- and γ-secretases, which releases receptor fragments for downstream signaling. Our previous work demonstrated that proteolytic processing of p75 NTR in this manner is stimulated by oxidative stress in Lund Human Mesencephalic (LUHMES) cells, a dopaminergic neuronal cell line derived from human mesencephalic tissue. Considering the vulnerability of dopaminergic neurons in the ventral mesencephalon to oxidative stress and neurodegeneration associated with Parkinson's disease (PD), we investigated the role of this signaling cascade in neurodegeneration and explored cellular processes that govern oxidative stress-induced p75 NTR signaling. In the present study, we provide evidence that oxidative stress induces cleavage of p75 NTR by promoting c-Jun N-terminal Kinase (JNK)-dependent internalization of p75 NTR from the cell surface. This activation of p75 NTR signaling is counteracted by tropomyosin-related kinase (Trk) receptor signaling; however, oxidative stress leads to Trk receptor downregulation, thereby enhancing p75 NTR processing. Importantly, we demonstrate that this pathway can be inhibited by LM11a-31, a small molecule modulator of p75 NTR , thereby conferring protection against neurodegeneration. Treatment with LM11a-31 significantly reduced p75 NTR cleavage and neuronal death associated with oxidative stress. These findings reveal novel mechanisms underlying activation of p75 NTR in response to oxidative stress, underscore a key role for p75 NTR in dopaminergic neurodegeneration, and highlight p75 NTR as a potential therapeutic target for reducing neurodegeneration in PD.
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2
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Zhao H, Fan S, Sun J. Delayed Wound Healing in the Elderly and a New Therapeutic Target: CD271. Curr Stem Cell Res Ther 2024; 19:316-323. [PMID: 37016526 DOI: 10.2174/1574888x18666230403083603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 11/21/2022] [Accepted: 12/29/2022] [Indexed: 04/06/2023]
Abstract
With the development of society, the global population is showing a trend of aging. It is well known that age is one of the factors affecting wound healing. Aging compromises the normal physiological process of wound healing, such as the change of skin structure, the decrease of growth factors, the deceleration of cell proliferation, and the weakening of migration ability, hence delaying wound healing. At present, research in adult stem cell-related technology and its derived regenerative medicine provides a novel idea for the treatment of senile wounds. Studies have confirmed that CD271 (P75 neurotropism receptor/P75NTR)-positive cells (CD271+ cells) are a kind of stem cells with a stronger ability of proliferation, differentiation, migration and secretion than CD271 negative (CD271- cells). Meanwhile, the total amount and distribution of CD271 positive cells in different ages of skin are also different, which may be related to the delayed wound healing of aging skin. Therefore, this article reviews the relationship between CD271+ cells and senile wounds and discusses a new scheme for the treatment of senile wounds.
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Affiliation(s)
- Hongqing Zhao
- Department of Plastic Surgery, Jinzhou Medical University, Jinzhou, 121001, Liaoning Province, China
- Department of Burns and Plastic Surgery, The Fourth Medical Center of Chinese PLA General Hospital, Beijing, 100048, China
| | - Sirui Fan
- Department of Plastic Surgery, Jinzhou Medical University, Jinzhou, 121001, Liaoning Province, China
| | - Jiachen Sun
- Department of Burns and Plastic Surgery, The Fourth Medical Center of Chinese PLA General Hospital, Beijing, 100048, China
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3
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Danelon V, Garret-Thomson SC, Almo SC, Lee FS, Hempstead BL. Immune activation of the p75 neurotrophin receptor: implications in neuroinflammation. Front Mol Neurosci 2023; 16:1305574. [PMID: 38106879 PMCID: PMC10722190 DOI: 10.3389/fnmol.2023.1305574] [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: 10/02/2023] [Accepted: 11/10/2023] [Indexed: 12/19/2023] Open
Abstract
Despite structural similarity with other tumor necrosis factor receptor superfamily (TNFRSF) members, the p75 neurotrophin receptor (p75NTR, TNFR16) mediates pleiotropic biological functions not shared with other TNFRs. The high level of p75NTR expression in the nervous system instead of immune cells, its utilization of co-receptors, and its interaction with soluble dimeric, rather than soluble or cell-tethered trimeric ligands are all characteristics which distinguish it from most other TNFRs. Here, we compare these attributes to other members of the TNFR superfamily. In addition, we describe the recent evolutionary adaptation in B7-1 (CD80), an immunoglobulin (Ig) superfamily member, which allows engagement to neuronally-expressed p75NTR. B7-1-mediated binding to p75NTR occurs in humans and other primates, but not lower mammals due to specific sequence changes that evolved recently in primate B7-1. This discovery highlights an additional mechanism by which p75NTR can respond to inflammatory cues and trigger synaptic elimination in the brain through engagement of B7-1, which was considered to be immune-restricted. These observations suggest p75NTR does share commonality with other immune co-modulatory TNFR family members, by responding to immunoregulatory cues. The evolution of primate B7-1 to bind and elicit p75NTR-mediated effects on neuronal morphology and function are discussed in relationship to immune-driven modulation of synaptic actions during injury or inflammation.
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Affiliation(s)
- Victor Danelon
- Department of Medicine, Weill Cornell Graduate School of Medical Sciences, Weill Cornell Medicine, New York, NY, United States
| | | | - Steven C. Almo
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Francis S. Lee
- Department of Psychiatry, Weill Cornell Medicine, New York, NY, United States
| | - Barbara L. Hempstead
- Department of Medicine, Weill Cornell Graduate School of Medical Sciences, Weill Cornell Medicine, New York, NY, United States
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4
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The Nerve Growth Factor Receptor (NGFR/p75 NTR): A Major Player in Alzheimer's Disease. Int J Mol Sci 2023; 24:ijms24043200. [PMID: 36834612 PMCID: PMC9965628 DOI: 10.3390/ijms24043200] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 02/01/2023] [Accepted: 02/03/2023] [Indexed: 02/09/2023] Open
Abstract
Alzheimer's disease (AD) represents the most prevalent type of dementia in elderly people, primarily characterized by brain accumulation of beta-amyloid (Aβ) peptides, derived from Amyloid Precursor Protein (APP), in the extracellular space (amyloid plaques) and intracellular deposits of the hyperphosphorylated form of the protein tau (p-tau; tangles or neurofibrillary aggregates). The Nerve growth factor receptor (NGFR/p75NTR) represents a low-affinity receptor for all known mammalians neurotrophins (i.e., proNGF, NGF, BDNF, NT-3 e NT-4/5) and it is involved in pathways that determine both survival and death of neurons. Interestingly, also Aβ peptides can blind to NGFR/p75NTR making it the "ideal" candidate in mediating Aβ-induced neuropathology. In addition to pathogenesis and neuropathology, several data indicated that NGFR/p75NTR could play a key role in AD also from a genetic perspective. Other studies suggested that NGFR/p75NTR could represent a good diagnostic tool, as well as a promising therapeutic target for AD. Here, we comprehensively summarize and review the current experimental evidence on this topic.
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5
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Subirada PV, Tovo A, Vaglienti MV, Luna Pinto JD, Saragovi HU, Sánchez MC, Anastasía A, Barcelona PF. Etiological Roles of p75 NTR in a Mouse Model of Wet Age-Related Macular Degeneration. Cells 2023; 12:cells12020297. [PMID: 36672232 PMCID: PMC9856885 DOI: 10.3390/cells12020297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/04/2023] [Accepted: 01/06/2023] [Indexed: 01/13/2023] Open
Abstract
Choroidal neovascularization (CNV) is a pathological angiogenesis of the choroidal plexus of the retina and is a key feature in the wet form of age-related macular degeneration. Mononuclear phagocytic cells (MPCs) are known to accumulate in the subretinal space, generating a chronic inflammatory state that promotes the growth of the choroidal neovasculature. However, how the MPCs are recruited and activated to promote CNV pathology is not fully understood. Using genetic and pharmacological tools in a mouse model of laser-induced CNV, we demonstrate a role for the p75 neurotrophin receptor (p75NTR) in the recruitment of MPCs, in glial activation, and in vascular alterations. After laser injury, expression of p75NTR is increased in activated Muller glial cells near the CNV area in the retina and the retinal pigmented epithelium (RPE)-choroid. In p75NTR knockout mice (p75NTR KO) with CNV, there is significantly reduced recruitment of MPCs, reduced glial activation, reduced CNV area, and the retinal function is preserved, as compared to wild type mice with CNV. Notably, a single intravitreal injection of a pharmacological p75NTR antagonist in wild type mice with CNV phenocopied the results of the p75NTR KO mice. Our results demonstrate that p75NTR is etiological in the development of CNV.
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Affiliation(s)
| | - Albana Tovo
- Departamento de Bioquímica Clínica, Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Universidad Nacional de Córdoba, Córdoba 5016, Argentina
| | - María Victoria Vaglienti
- Departamento de Bioquímica Clínica, Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Universidad Nacional de Córdoba, Córdoba 5016, Argentina
| | | | - Horacio Uri Saragovi
- Lady Davis Research Institute-Jewish General Hospital, Center for Experimental Therapeutics, Department of Pharmacology and Therapeutics, Department of Ophthalmology and Vision Sciences, McGill University, Montreal, QC H3T 1E2, Canada
| | - Maria Cecilia Sánchez
- Departamento de Bioquímica Clínica, Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Universidad Nacional de Córdoba, Córdoba 5016, Argentina
| | - Agustín Anastasía
- Instituto Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba 5016, Argentina
- Instituto Universitario de Ciencias Biomédicas de Córdoba (IUCBC), Córdoba 5016, Argentina
- Correspondence: (A.A.); (P.F.B.)
| | - Pablo Federico Barcelona
- Departamento de Bioquímica Clínica, Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Universidad Nacional de Córdoba, Córdoba 5016, Argentina
- Correspondence: (A.A.); (P.F.B.)
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6
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Luu BE, Mossa AH, Cammisotto PG, Uri Saragovi H, Campeau L. Modulation of diabetic kidney disease markers by an antagonist of p75 NTR in streptozotocin-treated mice. Gene 2022; 838:146729. [PMID: 35835402 DOI: 10.1016/j.gene.2022.146729] [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: 03/08/2022] [Revised: 06/12/2022] [Accepted: 07/08/2022] [Indexed: 11/25/2022]
Abstract
Two therapeutic agents targeting p75NTR pathways have been recently developed to alleviate retinopathy and bladder dysfunction in diabetes mellitus (DM), namely the small molecule p75NTR antagonist THX-B and a monoclonal antibody (mAb) that neutralizes the receptor ligand proNGF. We herein explore these two components in the context of diabetic kidney disease (DKD). Streptozotocin-injected mice were treated for 4 weeks with THX-B or anti-proNGF mAb. Kidneys were taken for quantification of microRNAs and mRNAs by RT-qPCR and for detection of proteins by immunohistochemistry, immunoblotting and ELISA. Blood was sampled to measure plasma levels of urea, creatinine, and albumin. DM led to increases in plasma concentrations of urea and creatinine and decreases in plasma albumin. Receptor p75NTR was expressed in kidneys and its expression was decreased by DM. All these changes were reversed by THX-B treatment while the effect of mAb was less pronounced. MicroRNAs tightly linked to DKD (miR-21-5p, miR-214-3p and miR-342-3p) were highly expressed in diabetic kidneys compared to healthy ones. Also, miR-146a, a marker of kidney inflammation, and mRNA levels of Fn-1 and Nphs, two markers of fibrosis and inflammation, were elevated in DM. Treatments with THX-B or mAb partially or completely reduced the expression of the aforementioned microRNAs and mRNAs. P75NTR antagonism and proNGF mAb might constitute new therapeutic tools to treat or slow down the progression of kidney disease in DM, along with other diabetic related complications. The translational potential of these strategies is currently being investigated.
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Affiliation(s)
- Bryan E Luu
- Lady Davis Institute, McGill University, Montreal, Quebec, Canada
| | - Abubakr H Mossa
- Lady Davis Institute, McGill University, Montreal, Quebec, Canada
| | | | - H Uri Saragovi
- Lady Davis Institute, McGill University, Montreal, Quebec, Canada; Pharmacology and Therapeutics, McGill University, Canada; Ophthalmology and Vision Sciences. McGill University, Montreal, Quebec H3T 1E2, Canada
| | - Lysanne Campeau
- Lady Davis Institute, McGill University, Montreal, Quebec, Canada; Division of Urology, Department of Surgery, Jewish General Hospital, Montreal, Quebec, Canada.
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7
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Tosolini AP, Sleigh JN, Surana S, Rhymes ER, Cahalan SD, Schiavo G. BDNF-dependent modulation of axonal transport is selectively impaired in ALS. Acta Neuropathol Commun 2022; 10:121. [PMID: 35996201 PMCID: PMC9396851 DOI: 10.1186/s40478-022-01418-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 07/29/2022] [Indexed: 02/08/2023] Open
Abstract
Axonal transport ensures long-range delivery of essential cargoes between proximal and distal compartments, and is needed for neuronal development, function, and survival. Deficits in axonal transport have been detected at pre-symptomatic stages in the SOD1G93A and TDP-43M337V mouse models of amyotrophic lateral sclerosis (ALS), suggesting that impairments in this critical process are fundamental for disease pathogenesis. Strikingly, in ALS, fast motor neurons (FMNs) degenerate first whereas slow motor neurons (SMNs) are more resistant, and this is a currently unexplained phenomenon. The main aim of this investigation was to determine the effects of brain-derived neurotrophic factor (BDNF) on in vivo axonal transport in different α-motor neuron (MN) subtypes in wild-type (WT) and SOD1G93A mice. We report that despite displaying similar basal transport speeds, stimulation of wild-type MNs with BDNF enhances in vivo trafficking of signalling endosomes specifically in FMNs. This BDNF-mediated enhancement of transport was also observed in primary ventral horn neuronal cultures. However, FMNs display selective impairment of axonal transport in vivo in symptomatic SOD1G93A mice, and are refractory to BDNF stimulation, a phenotype that was also observed in primary embryonic SOD1G93A neurons. Furthermore, symptomatic SOD1G93A mice display upregulation of the classical non-pro-survival truncated TrkB and p75NTR receptors in muscles, sciatic nerves, and Schwann cells. Altogether, these data indicate that cell- and non-cell autonomous BDNF signalling is impaired in SOD1G93A MNs, thus identifying a new key deficit in ALS.
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Affiliation(s)
- Andrew P Tosolini
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK.
- UCL Queen Square Motor Neuron Disease Centre, University College London, London, WC1N 3BG, UK.
| | - James N Sleigh
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK
- UCL Queen Square Motor Neuron Disease Centre, University College London, London, WC1N 3BG, UK
- UK Dementia Research Institute, University College London, London, WC1E 6BT, UK
| | - Sunaina Surana
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK
- UCL Queen Square Motor Neuron Disease Centre, University College London, London, WC1N 3BG, UK
- UK Dementia Research Institute, University College London, London, WC1E 6BT, UK
| | - Elena R Rhymes
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK
- UCL Queen Square Motor Neuron Disease Centre, University College London, London, WC1N 3BG, UK
| | - Stephen D Cahalan
- Comparative Neuromuscular Disease Laboratory, Department of Clinical Sciences and Services, Royal Veterinary College, University of London, London, NW1 0TU, UK
| | - Giampietro Schiavo
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK.
- UCL Queen Square Motor Neuron Disease Centre, University College London, London, WC1N 3BG, UK.
- UK Dementia Research Institute, University College London, London, WC1E 6BT, UK.
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8
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Eggert S, Kins S, Endres K, Brigadski T. Brothers in arms: proBDNF/BDNF and sAPPα/Aβ-signaling and their common interplay with ADAM10, TrkB, p75NTR, sortilin, and sorLA in the progression of Alzheimer's disease. Biol Chem 2022; 403:43-71. [PMID: 34619027 DOI: 10.1515/hsz-2021-0330] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 09/16/2021] [Indexed: 12/22/2022]
Abstract
Brain-derived neurotrophic factor (BDNF) is an important modulator for a variety of functions in the central nervous system (CNS). A wealth of evidence, such as reduced mRNA and protein level in the brain, cerebrospinal fluid (CSF), and blood samples of Alzheimer's disease (AD) patients implicates a crucial role of BDNF in the progression of this disease. Especially, processing and subcellular localization of BDNF and its receptors TrkB and p75 are critical determinants for survival and death in neuronal cells. Similarly, the amyloid precursor protein (APP), a key player in Alzheimer's disease, and its cleavage fragments sAPPα and Aβ are known for their respective roles in neuroprotection and neuronal death. Common features of APP- and BDNF-signaling indicate a causal relationship in their mode of action. However, the interconnections of APP- and BDNF-signaling are not well understood. Therefore, we here discuss dimerization properties, localization, processing by α- and γ-secretase, relevance of the common interaction partners TrkB, p75, sorLA, and sortilin as well as shared signaling pathways of BDNF and sAPPα.
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Affiliation(s)
- Simone Eggert
- Department of Human Biology and Human Genetics, University of Kaiserslautern, Erwin-Schrödinger-Str. 13, D-67663 Kaiserslautern, Germany
| | - Stefan Kins
- Department of Human Biology and Human Genetics, University of Kaiserslautern, Erwin-Schrödinger-Str. 13, D-67663 Kaiserslautern, Germany
| | - Kristina Endres
- Department of Psychiatry and Psychotherapy, University Medical Center, Johannes Gutenberg-University Mainz, D-55131 Mainz, Germany
| | - Tanja Brigadski
- Department of Informatics and Microsystem Technology, University of Applied Sciences Kaiserslautern, D-66482 Zweibrücken, Germany
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9
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Sankorrakul K, Qian L, Thangnipon W, Coulson EJ. Is there a role for the p75 neurotrophin receptor in mediating degeneration during oxidative stress and after hypoxia? J Neurochem 2021; 158:1292-1306. [PMID: 34109634 DOI: 10.1111/jnc.15451] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 06/01/2021] [Accepted: 06/04/2021] [Indexed: 12/21/2022]
Abstract
Cholinergic basal forebrain (cBF) neurons are particularly vulnerable to degeneration following trauma and in neurodegenerative conditions. One reason for this is their characteristic expression of the p75 neurotrophin receptor (p75NTR ), which is up-regulated and mediates neuronal death in a range of neurological and neurodegenerative conditions, including dementia, stroke and ischaemia. The signalling pathway by which p75NTR signals cell death is incompletely characterised, but typically involves activation by neurotrophic ligands and signalling through c-Jun kinase, resulting in caspase activation via mitochondrial apoptotic signalling pathways. Less well appreciated is the link between conditions of oxidative stress and p75NTR death signalling. Here, we review the literature describing what is currently known regarding p75NTR death signalling in environments of oxidative stress and hypoxia to highlight the overlap in signalling pathways and the implications for p75NTR signalling in cBF neurons. We propose that there is a causal relationship and define key questions to test this assertion.
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Affiliation(s)
- Kornraviya Sankorrakul
- School of Biomedical Sciences, Faculty of Medicine and Queensland Brain Institute, Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Qld., Australia.,Research Center for Neuroscience, Institute of Molecular Biosciences, Mahidol University, Salaya, Thailand
| | - Lei Qian
- School of Biomedical Sciences, Faculty of Medicine and Queensland Brain Institute, Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Qld., Australia
| | - Wipawan Thangnipon
- Research Center for Neuroscience, Institute of Molecular Biosciences, Mahidol University, Salaya, Thailand
| | - Elizabeth J Coulson
- School of Biomedical Sciences, Faculty of Medicine and Queensland Brain Institute, Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Qld., Australia
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10
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Dorschner BW, Wiedemuth R, Funke AC, Gentzel M, Rogers ML, Brenner S, Thieme S. Listening to the Whispers in Neuroimmune Crosstalk: A Comprehensive Workflow to Investigate Neurotrophin Receptor p75NTR Under Endogenous, Low Abundance Conditions. Front Immunol 2021; 12:648283. [PMID: 33936068 PMCID: PMC8085361 DOI: 10.3389/fimmu.2021.648283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 03/22/2021] [Indexed: 11/24/2022] Open
Abstract
Inflammatory conditions are critically influenced by neuroimmune crosstalk. Cytokines and neurotrophic factors shape the responses of both nervous and immune systems. Although much progress has been made, most findings to date are based on expression of recombinant (tagged) proteins. The examination of receptor interactions by immunoprecipitation (IP) at endogenous levels provides further insight into the more subtle regulations of immune responses. Here, we present a comprehensive workflow and an optimized IP protocol that provide step-by-step instructions to investigate neurotrophin receptor p75NTR at endogenous, low abundance levels: from lysate preparation and confirmation of receptor expression to antibody validation and successful detection of protein-protein interactions. We employ human melanoma cell line A375 to validate specific antibodies and IP conditions, and apply these methods to explore p75NTR interactions in human leukemic plasmacytoid dendritic cell line PMDC05 detecting 14-3-3ϵ:p75NTR interaction in this cell type. With p75NTR as an exemplary protein, our approach provides a strategy to detect specific interaction partners even under endogenous, low abundance expression conditions.
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Affiliation(s)
- Benjamin W. Dorschner
- Experimental Hematology, Department of Pediatrics, University Clinic Carl Gustav Carus, Dresden, Germany
| | - Ralf Wiedemuth
- Experimental Hematology, Department of Pediatrics, University Clinic Carl Gustav Carus, Dresden, Germany
| | - Ann-Christin Funke
- Experimental Hematology, Department of Pediatrics, University Clinic Carl Gustav Carus, Dresden, Germany
| | - Marc Gentzel
- Molecular Analysis - Mass Spectrometry, Center for Molecular and Cellular Bioengineering (CMCB), Technische Universitaet Dresden, Dresden, Germany
| | - Mary-Louise Rogers
- Centre for Neuroscience, College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Sebastian Brenner
- Experimental Hematology, Department of Pediatrics, University Clinic Carl Gustav Carus, Dresden, Germany
| | - Sebastian Thieme
- Experimental Hematology, Department of Pediatrics, University Clinic Carl Gustav Carus, Dresden, Germany
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11
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Fleury S, Boukhatem I, Le Blanc J, Welman M, Lordkipanidzé M. Tissue-Specificity of Antibodies Raised Against TrkB and p75 NTR Receptors; Implications for Platelets as Models of Neurodegenerative Diseases. Front Immunol 2021; 12:606861. [PMID: 33643311 PMCID: PMC7905091 DOI: 10.3389/fimmu.2021.606861] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 01/04/2021] [Indexed: 11/13/2022] Open
Abstract
Platelets and neurons share many similarities including comparable secretory granule types with homologous calcium-dependent secretory mechanisms as well as internalization, sequestration and secretion of many neurotransmitters. Thus, platelets present a high potential to be used as peripheral biomarkers to reflect neuronal pathologies. The brain-derived neurotrophic factor (BDNF) acts as a neuronal growth factor involved in learning and memory through the binding of two receptors, the tropomyosin receptor kinase B (TrkB) and the 75 kDa pan-neurotrophic receptor (p75NTR). In addition to its expression in the central nervous system, BDNF is found in much greater quantities in blood circulation, where it is largely stored within platelets. Levels 100- to 1,000-fold those of neurons make platelets the most important peripheral reservoir of BDNF. This led us to hypothesize that platelets would express canonical BDNF receptors, i.e., TrkB and p75NTR, and that the receptors on platelets would bear significant resemblance to the ones found in the brain. However, herein we report discrepancies regarding detection of these receptors using antibody-based assays, with antibodies displaying important tissue-specificity. The currently available antibodies raised against TrkB and p75NTR should therefore be used with caution to study platelets as models for neurological disorders. Rigorous characterization of antibodies and bioassays appears critical to understand the interplay between platelet and neuronal biology of BDNF.
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Affiliation(s)
- Samuel Fleury
- Research Center, Montreal Heart Institute, Montreal, QC, Canada.,Faculty of Pharmacy, Université de Montréal, Montreal, QC, Canada
| | - Imane Boukhatem
- Research Center, Montreal Heart Institute, Montreal, QC, Canada.,Faculty of Pharmacy, Université de Montréal, Montreal, QC, Canada
| | - Jessica Le Blanc
- Research Center, Montreal Heart Institute, Montreal, QC, Canada.,Faculty of Pharmacy, Université de Montréal, Montreal, QC, Canada
| | - Mélanie Welman
- Research Center, Montreal Heart Institute, Montreal, QC, Canada
| | - Marie Lordkipanidzé
- Research Center, Montreal Heart Institute, Montreal, QC, Canada.,Faculty of Pharmacy, Université de Montréal, Montreal, QC, Canada
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12
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Revising the mechanism of p75NTR activation: intrinsically monomeric state of death domains invokes the "helper" hypothesis. Sci Rep 2020; 10:13686. [PMID: 32792564 PMCID: PMC7427093 DOI: 10.1038/s41598-020-70721-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 07/27/2020] [Indexed: 02/03/2023] Open
Abstract
The neurotrophin receptor p75NTR plays crucial roles in neuron development and regulates important neuronal processes like degeneration, apoptosis and cell survival. At the same time the detailed mechanism of signal transduction is unclear. One of the main hypotheses known as the snail-tong mechanism assumes that in the inactive state, the death domains interact with each other and in response to ligand binding there is a conformational change leading to their exposure. Here, we show that neither rat nor human p75NTR death domains homodimerize in solution. Moreover, there is no interaction between the death domains in a more native context: the dimerization of transmembrane domains in liposomes and the presence of activating mutation in extracellular juxtamembrane region do not lead to intracellular domain interaction. These findings suggest that the activation mechanism of p75NTR should be revised. Thus, we propose a novel model of p75NTR functioning based on interaction with "helper" protein.
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Delivanoglou N, Boziki M, Theotokis P, Kesidou E, Touloumi O, Dafi N, Nousiopoulou E, Lagoudaki R, Grigoriadis N, Charalampopoulos I, Simeonidou C. Spatio-temporal expression profile of NGF and the two-receptor system, TrkA and p75NTR, in experimental autoimmune encephalomyelitis. J Neuroinflammation 2020; 17:41. [PMID: 31996225 PMCID: PMC6990493 DOI: 10.1186/s12974-020-1708-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 01/09/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Nerve growth factor (NGF) and its receptors, tropomyosin receptor kinase A (TrkA) and pan-neurotrophin receptor p75 (p75NTR), are known to play bidirectional roles between the immune and nervous system. There are only few studies with inconclusive results concerning the expression pattern and role of NGF, TrkA, and p75NTR (NGF system) under the neuroinflammatory conditions in multiple sclerosis (MS) and its mouse model, the experimental autoimmune encephalomyelitis (EAE). The aim of this study is to investigate the temporal expression in different cell types of NGF system in the central nervous system (CNS) during the EAE course. METHODS EAE was induced in C57BL/6 mice 6-8 weeks old. CNS tissue samples were collected on specific time points: day 10 (D10), days 20-22 (acute phase), and day 50 (chronic phase), compared to controls. Real-time PCR, Western Blot, histochemistry, and immunofluorescence were performed throughout the disease course for the detection of the spatio-temporal expression of the NGF system. RESULTS Our findings suggest that both NGF and its receptors, TrkA and p75NTR, are upregulated during acute and chronic phase of the EAE model in the inflammatory lesions in the spinal cord. NGF and its receptors were co-localized with NeuN+ cells, GAP-43+ axons, GFAP+ cells, Arginase1+ cells, and Mac3+ cells. Furthermore, TrkA and p75NTR were sparsely detected on CNPase+ cells within the inflammatory lesion. Of high importance is our observation that despite EAE being a T-mediated disease, only NGF and p75NTR were shown to be expressed by B lymphocytes (B220+ cells) and no expression on T lymphocytes was noticed. CONCLUSION Our results indicate that the components of the NGF system are subjected to differential regulation during the EAE disease course. The expression pattern of NGF, TrkA, and p75NTR is described in detail, suggesting possible functional roles in neuroprotection, neuroregeneration, and remyelination by direct and indirect effects on the components of the immune system.
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MESH Headings
- Animals
- B-Lymphocytes/metabolism
- Brain/pathology
- Encephalomyelitis, Autoimmune, Experimental/genetics
- Encephalomyelitis, Autoimmune, Experimental/metabolism
- Encephalomyelitis, Autoimmune, Experimental/pathology
- Female
- Gene Expression Regulation/genetics
- Immunohistochemistry
- Mice
- Mice, Inbred C57BL
- Nerve Growth Factor/biosynthesis
- Nerve Growth Factor/genetics
- Receptor, trkA/biosynthesis
- Receptor, trkA/genetics
- Receptors, Nerve Growth Factor/biosynthesis
- Receptors, Nerve Growth Factor/genetics
- Spinal Cord/metabolism
- Spinal Cord/pathology
- T-Lymphocytes/metabolism
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Affiliation(s)
- Nickoleta Delivanoglou
- Laboratory of Experimental Neurology and Neuroimmunology, B' Department of Neurology, AHEPA University Hospital, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
- Laboratory of Experimental Physiology, Department of Physiology and Pharmacology, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Marina Boziki
- Laboratory of Experimental Neurology and Neuroimmunology, B' Department of Neurology, AHEPA University Hospital, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Paschalis Theotokis
- Laboratory of Experimental Neurology and Neuroimmunology, B' Department of Neurology, AHEPA University Hospital, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Evangelia Kesidou
- Laboratory of Experimental Neurology and Neuroimmunology, B' Department of Neurology, AHEPA University Hospital, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
- Laboratory of Experimental Physiology, Department of Physiology and Pharmacology, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Olga Touloumi
- Laboratory of Experimental Neurology and Neuroimmunology, B' Department of Neurology, AHEPA University Hospital, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Nikolina Dafi
- Laboratory of Experimental Neurology and Neuroimmunology, B' Department of Neurology, AHEPA University Hospital, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Evangelia Nousiopoulou
- Laboratory of Experimental Neurology and Neuroimmunology, B' Department of Neurology, AHEPA University Hospital, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Roza Lagoudaki
- Laboratory of Experimental Neurology and Neuroimmunology, B' Department of Neurology, AHEPA University Hospital, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Nikolaos Grigoriadis
- Laboratory of Experimental Neurology and Neuroimmunology, B' Department of Neurology, AHEPA University Hospital, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Ioannis Charalampopoulos
- Laboratory of Pharmacology, Department of Basic Sciences, School of Medicine, University of Crete, Heraklion, Greece
- Institute of Molecular Biology and Biotechnology, Foundation of Research and Technology Hellas, Heraklion, Greece
| | - Constantina Simeonidou
- Laboratory of Experimental Physiology, Department of Physiology and Pharmacology, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece.
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Dissecting Mechanisms of Melanoma Resistance to BRAF and MEK Inhibitors Revealed Genetic and Non-Genetic Patient- and Drug-Specific Alterations and Remarkable Phenotypic Plasticity. Cells 2020; 9:cells9010142. [PMID: 31936151 PMCID: PMC7017165 DOI: 10.3390/cells9010142] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 12/29/2019] [Accepted: 01/03/2020] [Indexed: 12/14/2022] Open
Abstract
The clinical benefit of MAPK pathway inhibition in BRAF-mutant melanoma patients is limited by the development of acquired resistance. Using drug-naïve cell lines derived from tumor specimens, we established a preclinical model of melanoma resistance to vemurafenib or trametinib to provide insight into resistance mechanisms. Dissecting the mechanisms accompanying the development of resistance, we have shown that (i) most of genetic and non-genetic alterations are triggered in a cell line- and/or drug-specific manner; (ii) several changes previously assigned to the development of resistance are induced as the immediate response to the extent measurable at the bulk levels; (iii) reprogramming observed in cross-resistance experiments and growth factor-dependence restricted by the drug presence indicate that phenotypic plasticity of melanoma cells largely contributes to the sustained resistance. Whole-exome sequencing revealed novel genetic alterations, including a frameshift variant of RBMX found exclusively in phospho-AKThigh resistant cell lines. There was no similar pattern of phenotypic alterations among eleven resistant cell lines, including expression/activity of crucial regulators, such as MITF, AXL, SOX, and NGFR, which suggests that patient-to-patient variability is richer and more nuanced than previously described. This diversity should be considered during the development of new strategies to circumvent the acquired resistance to targeted therapies.
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15
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16
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Fast-diffusing p75 NTR monomers support apoptosis and growth cone collapse by neurotrophin ligands. Proc Natl Acad Sci U S A 2019; 116:21563-21572. [PMID: 31515449 PMCID: PMC6815156 DOI: 10.1073/pnas.1902790116] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Neurotrophins (NTs) are homodimeric growth factors displaying fundamental roles in the nervous system. Their activity stems from binding and activation of 3 different receptor types in nervous cell membranes. The p75 NT receptor (p75NTR) was the first to be discovered in 1986; nevertheless, for the numerous structural and functional facets so far reported, its activation mechanisms have remained elusive. Here, we demonstrate that its pleiotropic functions are regulated by different redistributions of the receptors, which crucially depend on the available NT and on the involved subcellular compartment but are unrelated to its oligomerization state. Single-particle studies proved receptors to be monomers with a fast-diffusive behavior in the membrane with, at most, transient self-interactions on the millisecond time scale. The p75 neurotrophin (NT) receptor (p75NTR) plays a crucial role in balancing survival-versus-death decisions in the nervous system. Yet, despite 2 decades of structural and biochemical studies, a comprehensive, accepted model for p75NTR activation by NT ligands is still missing. Here, we present a single-molecule study of membrane p75NTR in living cells, demonstrating that the vast majority of receptors are monomers before and after NT activation. Interestingly, the stoichiometry and diffusion properties of the wild-type (wt) p75NTR are almost identical to those of a receptor mutant lacking residues previously believed to induce oligomerization. The wt p75NTR and mutated (mut) p75NTR differ in their partitioning in cholesterol-rich membrane regions upon nerve growth factor (NGF) stimulation: We argue that this is the origin of the ability of wt p75NTR , but not of mut p75NTR, to mediate immature NT (proNT)-induced apoptosis. Both p75NTR forms support proNT-induced growth cone retraction: We show that receptor surface accumulation is the driving force for cone collapse. Overall, our data unveil the multifaceted activity of the p75NTR monomer and let us provide a coherent interpretative frame of existing conflicting data in the literature.
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17
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Shen J, Sun D, Shao J, Chen Y, Pang K, Guo W, Lu B. Extracellular Juxtamembrane Motif Critical for TrkB Preformed Dimer and Activation. Cells 2019; 8:cells8080932. [PMID: 31430955 PMCID: PMC6721692 DOI: 10.3390/cells8080932] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 08/15/2019] [Accepted: 08/15/2019] [Indexed: 01/12/2023] Open
Abstract
Receptor tyrosine kinases are believed to be activated through ligand-induced dimerization. We now demonstrate that in cultured neurons, a substantial amount of endogenous TrkB, the receptor for brain-derived neurotrophic factor (BDNF), exists as an inactive preformed dimer, and the application of BDNF activates the pre-existing dimer. Deletion of the extracellular juxtamembrane motif (EJM) of TrkB increased the amount of preformed dimer, suggesting an inhibitory role of EJM on dimer formation. Further, binding of an agonistic antibody (MM12) specific to human TrkB-EJM activated the full-length TrkB and unexpectedly also truncated TrkB lacking ECD (TrkBdelECD365), suggesting that TrkB is activated by attenuating the inhibitory effect of EJM through MM12 binding-induced conformational changes. Finally, in cells co-expressing rat and human TrkB, MM12 could only activate TrkB human-human dimer but not TrkB human-rat TrkB dimer, indicating that MM12 binding to two TrkB monomers is required for activation. Our results support a model that TrkB preforms as an inactive dimer and BDNF induces TrkB conformation changes leading to its activation.
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Affiliation(s)
- Jianying Shen
- School of Pharmaceutical Sciences, IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing 100084, China
- Artemisinin Research Center, Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100084, China
| | - Dang Sun
- School of Pharmaceutical Sciences, IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing 100084, China
| | - Jingyu Shao
- School of Pharmaceutical Sciences, IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing 100084, China
| | - Yanbo Chen
- School of Pharmaceutical Sciences, IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing 100084, China
| | - Keliang Pang
- School of Pharmaceutical Sciences, IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing 100084, China
| | - Wei Guo
- School of Pharmaceutical Sciences, IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing 100084, China
- R & D Center for the Diagnosis and Treatment of Major Brain Diseases, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057, China
| | - Bai Lu
- School of Pharmaceutical Sciences, IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing 100084, China.
- R & D Center for the Diagnosis and Treatment of Major Brain Diseases, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057, China.
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18
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Zamai M, Trullo A, Giordano M, Corti V, Arza Cuesta E, Francavilla C, Cavallaro U, Caiolfa VR. Number and brightness analysis reveals that NCAM and FGF2 elicit different assembly and dynamics of FGFR1 in live cells. J Cell Sci 2019; 132:jcs.220624. [PMID: 30478195 DOI: 10.1242/jcs.220624] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 11/15/2018] [Indexed: 12/31/2022] Open
Abstract
Both fibroblast growth factor-2 (FGF2) and neural cell adhesion molecule (NCAM) trigger FGF receptor 1 (FGFR1) signaling; however, they induce remarkably distinct receptor trafficking and cellular responses. The molecular basis of such a dichotomy and the role of distinct types of ligand-receptor interaction remain elusive. Number of molecules and brightness (N&B) analysis revealed that FGF2 and NCAM promote different FGFR1 assembly and dynamics at the plasma membrane. NCAM stimulation elicits long-lasting cycles of short-lived FGFR1 monomers and multimers, a behavior that might reflect a rapid FGFR1 internalization and recycling. FGF2, instead, induces stable dimerization at the dose that stimulates cell proliferation. Reducing the occupancy of FGFR1 in response to low FGF2 doses causes a switch towards cyclically exposed and unstable receptor dimers, consistently with previously reported biphasic response to FGF2 and with the divergent signaling elicited by different ligand concentrations. Similar instability was observed upon altering the endocytic pathway. Thus, FGF2 and NCAM induce differential FGFR1 clustering at the cell surface, which might account for the distinct intracellular fate of the receptor and, hence, for the different signaling cascades and cellular responses.
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Affiliation(s)
- Moreno Zamai
- Centro di Imaging Sperimentale (CIS), Ospedale San Raffaele, IRCCS, Milan 20132, Italy.,Microscopy and Dynamic Imaging Unit, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid 28029, Spain
| | - Antonio Trullo
- Centro di Imaging Sperimentale (CIS), Ospedale San Raffaele, IRCCS, Milan 20132, Italy
| | - Marco Giordano
- Unit of Gynecological Oncology Research, European Institute of Oncology IRCCS, Milan 20141, Italy
| | - Valeria Corti
- Centro di Imaging Sperimentale (CIS), Ospedale San Raffaele, IRCCS, Milan 20132, Italy
| | - Elvira Arza Cuesta
- Microscopy and Dynamic Imaging Unit, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid 28029, Spain
| | - Chiara Francavilla
- Division of Molecular and Cellular Functions, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, UK
| | - Ugo Cavallaro
- Unit of Gynecological Oncology Research, European Institute of Oncology IRCCS, Milan 20141, Italy
| | - Valeria R Caiolfa
- Centro di Imaging Sperimentale (CIS), Ospedale San Raffaele, IRCCS, Milan 20132, Italy .,Microscopy and Dynamic Imaging Unit, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid 28029, Spain
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19
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Verykiou S, Alexander M, Edwards N, Plummer R, Chaudhry B, Lovat PE, Hill DS. Harnessing autophagy to overcome mitogen-activated protein kinase kinase inhibitor-induced resistance in metastatic melanoma. Br J Dermatol 2018; 180:346-356. [PMID: 30339727 PMCID: PMC7816093 DOI: 10.1111/bjd.17333] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/14/2018] [Indexed: 01/07/2023]
Abstract
BACKGROUND Patients with malignant melanoma often relapse after treatment with BRAF and/or mitogen-activated protein kinase kinase (MEK) inhibitors (MEKi) owing to development of drug resistance. OBJECTIVES To establish the temporal pattern of CD271 regulation during development of resistance by melanoma to trametinib, and determine the association between development of resistance to trametinib and induction of prosurvival autophagy. METHODS Immunohistochemistry for CD271 and p62 was performed on human naevi and primary malignant melanoma tumours. Western blotting was used to analyse expression of CD271, p62 and LC3 in melanoma subpopulations. Flow cytometry and immunofluorescence microscopy was used to evaluate trametinib-induced cell death and CD271 expression. MTS viability assays and zebrafish xenografts were used to evaluate the effect of CD271 and autophagy modulation on trametinib-resistant melanoma cell survival and invasion, respectively. RESULTS CD271 and autophagic signalling are increased in stage III primary melanomas vs. benign naevi. In vitro studies demonstrate MEKi of BRAF-mutant melanoma induced cytotoxic autophagy, followed by the emergence of CD271-expressing subpopulations. Trametinib-induced CD271 reduced autophagic flux, leading to activation of prosurvival autophagy and development of MEKi resistance. Treatment of CD271-expressing melanoma subpopulations with RNA interference and small-molecule inhibitors to CD271 reduced the development of MEKi resistance, while clinically applicable autophagy modulatory agents - including Δ9-tetrahydrocannabinol and Vps34 - reduced survival of MEKi-resistant melanoma cells. Combined MEK/autophagy inhibition also reduced the invasive and metastatic potential of MEKi-resistant cells in an in vivo zebrafish xenograft. CONCLUSIONS These results highlight a novel mechanism of MEKi-induced drug resistance and suggest that targeting autophagy may be a translatable approach to resensitize drug-resistant melanoma cells to the cytotoxic effects of MEKi.
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Affiliation(s)
- S Verykiou
- Institute of Cellular Medicine, Newcastle University, The Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, U.K.,Northern Institute for Cancer Research, Newcastle University, The Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, U.K
| | - M Alexander
- Institute of Cellular Medicine, Newcastle University, The Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, U.K
| | - N Edwards
- Institute of Cellular Medicine, Newcastle University, The Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, U.K
| | - R Plummer
- Northern Institute for Cancer Research, Newcastle University, The Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, U.K
| | - B Chaudhry
- Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, NE1 3BZ, U.K
| | - P E Lovat
- Institute of Cellular Medicine, Newcastle University, The Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, U.K.,Northern Institute for Cancer Research, Newcastle University, The Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, U.K
| | - D S Hill
- Institute of Cellular Medicine, Newcastle University, The Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, U.K.,Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, NE1 3BZ, U.K
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20
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The Structure of the Pro-domain of Mouse proNGF in Contact with the NGF Domain. Structure 2018; 27:78-89.e3. [PMID: 30393051 DOI: 10.1016/j.str.2018.09.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 06/14/2018] [Accepted: 09/25/2018] [Indexed: 01/19/2023]
Abstract
Nerve growth factor (NGF) is an important neurotrophic factor involved in the regulation of cell differentiation and survival of target neurons. Expressed as a proNGF precursor, NGF is matured by furin-mediated protease cleavage. Increasing evidence suggests that NGF and proNGF have distinct functional roles. While the structure of mature NGF is available, little is known about that of the pro-domain because of its dynamical structural features. We exploited an ad hoc hybrid strategy based on nuclear magnetic resonance and modeling validated by small-angle X-ray scattering to gain novel insights on the pro-domain, both in isolation and in the context of proNGF. We show that the isolated pro-domain is intrinsically unstructured but forms transient intramolecular contacts with mature NGF and has per se the ability to induce growth cone collapse, indicating functional independence. Our data represent an important step toward the structural and functional characterization of the properties of proNGF.
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21
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Structural insights into SorCS2-Nerve Growth Factor complex formation. Nat Commun 2018; 9:2979. [PMID: 30061605 PMCID: PMC6065357 DOI: 10.1038/s41467-018-05405-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 07/04/2018] [Indexed: 01/09/2023] Open
Abstract
Signaling of SorCS receptors by proneurotrophin ligands regulates neuronal plasticity, induces apoptosis and is associated with mental disorders. The detailed structure of SorCS2 and its extracellular specificity are unresolved. Here we report crystal structures of the SorCS2–NGF complex and unliganded SorCS2 ectodomain, revealing cross-braced SorCS2 homodimers with two NGF dimers bound in a 2:4 stoichiometry. Five out of six SorCS2 domains directly contribute to dimer formation and a C-terminal membrane proximal unreported domain, with an RNA recognition motif fold, locks the dimer in an intermolecular head-to-tail interaction. The complex structure shows an altered SorCS2 conformation indicating substantial structural plasticity. Both NGF dimer chains interact exclusively with the top face of a SorCS2 β-propeller. Biophysical experiments reveal that NGF, proNGF, and proBDNF bind at this site on SorCS2. Taken together, our data reveal a structurally flexible SorCS2 receptor that employs the large β-propeller as a ligand binding platform. The Sortilin-related CNS-expressed receptor 2 (SorCS2)–proneurotrophin signaling system regulates neuronal plasticity and its dysfunction is linked to schizophrenia. Here the authors present the structures of the SorCS2 ectodomain alone and in complex with Nerve Growth Factor, which provides insights into SorCS2 ligand binding and signaling.
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22
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Drug Targets in Neurotrophin Signaling in the Central and Peripheral Nervous System. Mol Neurobiol 2018; 55:6939-6955. [PMID: 29372544 DOI: 10.1007/s12035-018-0885-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 01/08/2018] [Indexed: 12/12/2022]
Abstract
Neurotrophins are a family of proteins that play an important role in the regulation of the growth, survival, and differentiation of neurons in the central and peripheral nervous system. Neurotrophins were earlier characterized by their role in early development, growth, maintenance, and the plasticity of the nervous system during development, but recent findings also indicate their complex role during normal physiology in both neuronal and non-neuronal tissues. Therefore, it is important to recognize a deficiency in the expression of neurotrophins, a major factor driving the debilitating features of several neurologic and psychiatric diseases/disorders. On the other hand, overexpression of neurotrophins is well known to play a critical role in pathogenesis of chronic pain and afferent sensitization, underlying conditions such as lower urinary tract symptoms (LUTS)/disorders and osteoarthritis. The existence of a redundant receptor system of high-and low-affinity receptors accounts for the diverse, often antagonistic, effects of neurotrophins in neurons and non-neuronal tissues in a spatial and temporal manner. In addition, studies looking at bladder dysfunction because of conditions such as spinal cord injury and diabetes mellitus have found alterations in the levels of these neurotrophins in the bladder, as well as in sensory afferent neurons, which further opens a new avenue for therapeutic targets. In this review, we will discuss the characteristics and roles of key neurotrophins and their involvement in the central and periphery nervous system in both normal and diseased conditions.
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Saadipour K, MacLean M, Pirkle S, Ali S, Lopez-Redondo ML, Stokes DL, Chao MV. The transmembrane domain of the p75 neurotrophin receptor stimulates phosphorylation of the TrkB tyrosine kinase receptor. J Biol Chem 2017; 292:16594-16604. [PMID: 28821608 PMCID: PMC5633122 DOI: 10.1074/jbc.m117.788729] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 07/31/2017] [Indexed: 01/19/2023] Open
Abstract
The function of protein products generated from intramembraneous cleavage by the γ-secretase complex is not well defined. The γ-secretase complex is responsible for the cleavage of several transmembrane proteins, most notably the amyloid precursor protein that results in Aβ, a transmembrane (TM) peptide. Another protein that undergoes very similar γ-secretase cleavage is the p75 neurotrophin receptor. However, the fate of the cleaved p75 TM domain is unknown. p75 neurotrophin receptor is highly expressed during early neuronal development and regulates survival and process formation of neurons. Here, we report that the p75 TM can stimulate the phosphorylation of TrkB (tyrosine kinase receptor B). In vitro phosphorylation experiments indicated that a peptide representing p75 TM increases TrkB phosphorylation in a dose- and time-dependent manner. Moreover, mutagenesis analyses revealed that a valine residue at position 264 in the rat p75 neurotrophin receptor is necessary for the ability of p75 TM to induce TrkB phosphorylation. Because this residue is just before the γ-secretase cleavage site, we then investigated whether the p75(αγ) peptide, which is a product of both α- and γ-cleavage events, could also induce TrkB phosphorylation. Experiments using TM domains from other receptors, EGFR and FGFR1, failed to stimulate TrkB phosphorylation. Co-immunoprecipitation and biochemical fractionation data suggested that p75 TM stimulates TrkB phosphorylation at the cell membrane. Altogether, our results suggest that TrkB activation by p75(αγ) peptide may be enhanced in situations where the levels of the p75 receptor are increased, such as during brain injury, Alzheimer's disease, and epilepsy.
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Affiliation(s)
- Khalil Saadipour
- From the Departments of Cell Biology, Physiology & Neuroscience, and Psychiatry, Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, New York, New York 10016
| | - Michael MacLean
- From the Departments of Cell Biology, Physiology & Neuroscience, and Psychiatry, Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, New York, New York 10016
| | - Sean Pirkle
- From the Departments of Cell Biology, Physiology & Neuroscience, and Psychiatry, Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, New York, New York 10016
| | - Solav Ali
- From the Departments of Cell Biology, Physiology & Neuroscience, and Psychiatry, Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, New York, New York 10016
| | - Maria-Luisa Lopez-Redondo
- From the Departments of Cell Biology, Physiology & Neuroscience, and Psychiatry, Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, New York, New York 10016
| | - David L Stokes
- From the Departments of Cell Biology, Physiology & Neuroscience, and Psychiatry, Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, New York, New York 10016
| | - Moses V Chao
- From the Departments of Cell Biology, Physiology & Neuroscience, and Psychiatry, Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, New York, New York 10016
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Angelov B, Angelova A. Nanoscale clustering of the neurotrophin receptor TrkB revealed by super-resolution STED microscopy. NANOSCALE 2017; 9:9797-9804. [PMID: 28682396 DOI: 10.1039/c7nr03454g] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The nanoscale organization of the tropomyosin-related kinase receptor type B (TrkB), a promising therapeutic target for severe neurodegenerative and psychiatric disorders, is examined by stimulated emission depletion (STED) microscopy using the deconvoluted gated STED option. The performed immunofluorescence nanoscopic subdiffraction imaging of the membrane receptor localization reveals that clusters of oligomeric TrkB states and randomly organized nanodomains are formed in the membranes of differentiated human neuroblastoma SH-SY5Y cells, which are studied as an in vitro model of neurodegeneration. Despite that the monomeric (isolated) states of the receptor cannot be distinguished from its dimeric forms in such images, TrkB receptor dimers (or couple of individual monomers) are visualized at super-resolution as single pixels in the magnified Huygens-deconvoluted gated STED images. The clusters of higher-order TrkB oligomers are of dynamic nature rather than of a fixed stoichiometry. The propensity for membrane protein clustering as well as the dissociation of the TrkB receptors nanodomains can be modulated by neurotherapeutic formulations containing ω-3 polyunsaturated docosahexaenoic acid (DHA). Nanomolar concentrations of DHA change the receptor topology and lead to disruption of the cluster phases. This result is of therapeutic importance for TrkB receptor availability upon ligand binding as DHA favours the mobility and the dynamic distribution of the protein populations in the cell membranes.
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Affiliation(s)
- Borislav Angelov
- Institute of Physics, ELI Beamlines, Academy of Sciences of the Czech Republic, Na Slovance 2, CZ-18221 Prague, Czech Republic
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PROneurotrophins and CONSequences. Mol Neurobiol 2017; 55:2934-2951. [DOI: 10.1007/s12035-017-0505-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 03/21/2017] [Indexed: 01/12/2023]
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26
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Abstract
In the last few years, exciting properties have emerged regarding the activation, signaling, mechanisms of action, and therapeutic targeting of the two types of neurotrophin receptors: the p75NTR with its intracellular and extracellular peptides, the Trks, their precursors and their complexes. This review summarizes these new developments, with particular focus on neurodegenerative diseases. Based on the evolving knowledge, innovative concepts have been formulated regarding the pathogenesis of these diseases, especially the Alzheimer's and two other, the Parkinson's and Huntington's diseases. The medical progresses include original procedures of diagnosis, started from studies in mice and now investigated for human application, based on innovative classes of receptor agonists and blockers. In parallel, comprehensive studies have been and are being carried out for the development of drugs. The relevance of these studies is based on the limitations of the therapies employed until recently, especially for the treatment of Alzheimer's patients. Starting from well known drugs, previously employed for non-neurodegenerative diseases, the ongoing progress has lead to the development of small molecules that cross rapidly the blood-brain barrier. Among these molecules the most promising are specific blockers of the p75NTR receptor. Additional drugs, that activate Trk receptors, were shown effective against synaptic loss and memory deficits. In the near future such approaches, coordinated with treatments with monoclonal antibodies and with developments in the microRNA field, are expected to improve the therapy of neurodegenerative diseases, and may be relevant also for other human disease conditions.
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Affiliation(s)
- Jacopo Meldolesi
- Department of Neuroscience, Vita-Salute San Raffaele University and Scientific Institute San Raffaele, via Olgettina 58, 20132 Milan, Italy.
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27
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Li J, Wang M, Peng C, Bei C. [Research progress of P75 neurotrophin receptor and new idea of nonunion treatment]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 2017; 31:105-109. [PMID: 29798638 PMCID: PMC9548035 DOI: 10.7507/1002-1892.201609008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 09/04/2016] [Revised: 12/03/2016] [Indexed: 11/03/2022]
Abstract
Objective To review the research progress of P75 neurotrophin receptor (P75NTR) so as to clarify its mechanism, and to explore its relationship with nonunion so as to provide a new idea for the treatment of nonunion. Methods The related domestic and foreign literature of P75NTR in recent years was extensively reviewed, summarized, and analyzed to find out the mechanism of action of P75NTR and the pathological factors of nonunion formation. Results P75NTR can express in nonunion tissues and lead to defect of fibrin degradation and inhibition of angiogenesis, which play an important role in the pathogenesis of nonunion. Conclusion It needs to be confirmed by further study whether the purpose of treating nonunion can be achieved by blocking the effects described above of P75NTR.
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Affiliation(s)
- Jiayong Li
- Department of Limb Trauma, Affiliated Hospital of Guilin Medical College, Guilin Guangxi, 541001, P.R.China
| | - Ming Wang
- Department of Limb Trauma, Affiliated Hospital of Guilin Medical College, Guilin Guangxi, 541001, P.R.China
| | - Chengfei Peng
- Department of Limb Trauma, Affiliated Hospital of Guilin Medical College, Guilin Guangxi, 541001, P.R.China
| | - Chaoyong Bei
- Department of Limb Trauma, Affiliated Hospital of Guilin Medical College, Guilin Guangxi, 541001,
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28
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Budzinska M, Wicher KB, Terenzio M. Neuronal Roles of the Bicaudal D Family of Motor Adaptors. VITAMINS AND HORMONES 2016; 104:133-152. [PMID: 28215293 DOI: 10.1016/bs.vh.2016.11.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
All cell types rely on active intracellular cargo transport to shuttle essential cellular components such as proteins, lipids, RNA, and even organelles from the center to the periphery and vice versa. Additionally, several signaling pathways take advantage of intracellular transport to propagate their signals by moving activated receptors and protein effectors to specific locations inside the cell. Neurons particularly, being a very polarized cell type, are highly dependent on molecular motors for the anterograde and retrograde delivery of essential cellular components and signaling molecules. For these reasons, motor adaptor proteins have been extensively investigated in regard to their role in physiology and pathology of the nervous system. In this chapter, we will concentrate on a family of motor adaptor proteins, Bicaudal D (BICD), and their function in the context of the nervous system. BicD was originally described as essential for the correct localization of maternal mRNAs in Drosophila's oocyte and a regulator of the Golgi to ER retrograde transport in mammalian cells. Both mammalian BICD1 and BICD2 are highly expressed in the nervous system during development, and their importance in neuronal homeostasis has been recently under scrutiny. Several mutations in BICD2 have been linked to the development of neuromuscular diseases, and BICD2 knockout (KO) mice display migration defects of the radial cerebellar granule cells. More in line with the overall topic of this book, BICD1 was identified as a novel regulator of neurotrophin (NT) signaling as its deletion leads to defective sorting of ligand-activated NT receptors with dramatic consequences on the NT-mediated signaling pathway.
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Affiliation(s)
- M Budzinska
- Molecular NeuroPathobiology Laboratory, UCL Institute of Neurology, University College London, London, United Kingdom
| | - K B Wicher
- Ossianix, Stevenage Bioscience Catalyst, Stevenage, United Kingdom
| | - M Terenzio
- Weizmann Institute of Science, Rehovot, Israel.
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29
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Vilar M. Structural Characterization of the p75 Neurotrophin Receptor: A Stranger in the TNFR Superfamily. VITAMINS AND HORMONES 2016; 104:57-87. [PMID: 28215307 DOI: 10.1016/bs.vh.2016.10.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Although p75 neurotrophin receptor (p75NTR) was the founding member of the tumor necrosis factor (TNF) receptor superfamily (TNFRSF), it is an atypical TNFRSF protein. p75NTR like TNF-R1 and Fas-R contain an extracellular domain with four cysteine-rich domains (CRD) and a death domain (DD) in the intracellular region. While TNFRSF proteins are activated by trimeric TNFSF ligands, p75NTR forms dimers activated by dimeric neurotrophins that are structurally unrelated to TNFSF proteins. In addition, although p75NTR shares with other members the interaction with the TNF receptor-associated factors to activate the NF-κB and cell death pathways, p75NTR does not interact with the DD-containing proteins FADD, TRADD, or MyD88. By contrast, the DD of p75NTR is able to recruit several protein interactors via a full catalog of DD interactions not described before in the TNFRSF. p75-DD forms homotypic symmetrical DD-DD complexes with itself and with the related p45-DD; forms heterotypic DD-CARD interactions with the RIP2-CARD domain, and forms a new interaction between a DD and RhoGDI. All these features, in addition to its promiscuous interactions with several ligands and coreceptors, its processing by α- and γ-secretases, the dimeric nature of its transmembrane domain and its "special" juxtamembrane region, make p75NTR a truly stranger in the TNFR superfamily. In this chapter, I will summarize the known structural aspects of p75NTR and I will analyze from a structural point of view, the similitudes and differences between p75NTR and the other members of the TNFRSF.
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Affiliation(s)
- M Vilar
- Molecular Basis of Neurodegeneration Unit, Institute of Biomedicine of Valencia (IBV-CSIC), València, Spain.
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30
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Abstract
The nerve growth factor family of growth factors, collectively known as neurotrophins, are evolutionarily ancient regulators with an enormous range of biological functions. Reflecting this long history and functional diversity, mechanisms for cellular responses to neurotrophins are exceptionally complex. Neurotrophins signal through p75
NTR, a member of the TNF receptor superfamily member, and through receptor tyrosine kinases (TrkA, TrkB, TrkC), often with opposite functional outcomes. The two classes of receptors are activated preferentially by proneurotrophins and mature processed neurotrophins, respectively. However, both receptor classes also possess neurotrophin-independent signaling functions. Signaling functions of p75
NTR and Trk receptors are each influenced by the other class of receptors. This review focuses on the mechanisms responsible for the functional interplay between the two neurotrophin receptor signaling systems.
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Affiliation(s)
- Mark Bothwell
- Department of Physiology & Biophysics, University of Washington, Seattle, WA, USA
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31
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Tanaka K, Kelly CE, Goh KY, Lim KB, Ibáñez CF. Death Domain Signaling by Disulfide-Linked Dimers of the p75 Neurotrophin Receptor Mediates Neuronal Death in the CNS. J Neurosci 2016; 36:5587-95. [PMID: 27194337 PMCID: PMC6601771 DOI: 10.1523/jneurosci.4536-15.2016] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2015] [Revised: 04/11/2016] [Accepted: 04/12/2016] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED The p75 neurotrophin receptor (p75(NTR)) mediates neuronal death in response to neural insults by activating a caspase apoptotic pathway. The oligomeric state and activation mechanism that enable p75(NTR) to mediate these effects have recently been called into question. Here, we have investigated mutant mice lacking the p75(NTR) death domain (DD) or a highly conserved transmembrane (TM) cysteine residue (Cys(259)) implicated in receptor dimerization and activation. Neuronal death induced by proneurotrophins or epileptic seizures was assessed and compared with responses in p75(NTR) knock-out mice and wild-type animals. Proneurotrophins induced apoptosis of cultured hippocampal and cortical neurons from wild-type mice, but mutant neurons lacking p75(NTR), only the p75(NTR) DD, or just Cys(259) were all equally resistant to proneurotrophin-induced neuronal death. Homo-FRET anisotropy experiments demonstrated that both NGF and proNGF induce conformational changes in p75(NTR) that are dependent on the TM cysteine. In vivo, neuronal death induced by pilocarpine-mediated seizures was significantly reduced in the hippocampus and somatosensory, piriform, and entorhinal cortices of all three strains of p75(NTR) mutant mice. Interestingly, the levels of protection observed in mice lacking the DD or only Cys(259) were identical to those of p75(NTR) knock-out mice even though the Cys(259) mutant differed from the wild-type receptor in only one amino acid residue. We conclude that, both in vitro and in vivo, neuronal death induced by p75(NTR) requires the DD and TM Cys(259), supporting the physiological relevance of DD signaling by disulfide-linked dimers of p75(NTR) in the CNS. SIGNIFICANCE STATEMENT A detailed understanding of the physiological significance of distinct structural determinants in the p75 neurotrophin receptor (p75(NTR)) is crucial for the identification of suitable drug targets in this receptor. We have tested the relevance of the p75(NTR) death domain (DD) and the highly conserved transmembrane residue Cys(259) for the ability of p75(NTR) to induce apoptosis in neurons of the CNS using gene-targeted mutant mice. The physiological importance of these determinants had been contested in some recent in vitro studies. Our results indicate a requirement for DD signaling by disulfide-linked dimers of p75(NTR) for neuronal death induced by proneurotrophins and epileptic seizures. These new mouse models will be useful for clarifying different aspects of p75(NTR) physiology.
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Affiliation(s)
- Kazuhiro Tanaka
- Department of Physiology, National University of Singapore, Singapore 117597, Singapore, Life Sciences Institute, National University of Singapore, Singapore 117456, Singapore
| | - Claire E Kelly
- Department of Neuroscience, Karolinska Institute, Stockholm S-17177, Sweden, and
| | - Ket Yin Goh
- Department of Physiology, National University of Singapore, Singapore 117597, Singapore, Life Sciences Institute, National University of Singapore, Singapore 117456, Singapore
| | - Kim Buay Lim
- Department of Physiology, National University of Singapore, Singapore 117597, Singapore, Life Sciences Institute, National University of Singapore, Singapore 117456, Singapore
| | - Carlos F Ibáñez
- Department of Physiology, National University of Singapore, Singapore 117597, Singapore, Life Sciences Institute, National University of Singapore, Singapore 117456, Singapore, Department of Neuroscience, Karolinska Institute, Stockholm S-17177, Sweden, and Stellenbosch Institute for Advanced Study, Wallenberg Research Centre at Stellenbosch University, Stellenbosch 7600, South Africa
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32
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Delbary-Gossart S, Lee S, Baroni M, Lamarche I, Arnone M, Canolle B, Lin A, Sacramento J, Salegio EA, Castel MN, Delesque-Touchard N, Alam A, Laboudie P, Ferzaz B, Savi P, Herbert JM, Manley GT, Ferguson AR, Bresnahan JC, Bono F, Beattie MS. A novel inhibitor of p75-neurotrophin receptor improves functional outcomes in two models of traumatic brain injury. Brain 2016; 139:1762-82. [PMID: 27084575 PMCID: PMC4892754 DOI: 10.1093/brain/aww074] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 02/20/2016] [Indexed: 11/14/2022] Open
Abstract
The p75 neurotrophin receptor is important in multiple physiological actions including neuronal survival and neurite outgrowth during development, and after central nervous system injury. We have discovered a novel piperazine-derived compound, EVT901, which interferes with p75 neurotrophin receptor oligomerization through direct interaction with the first cysteine-rich domain of the extracellular region. Using ligand binding assays with cysteine-rich domains-fused p75 neurotrophin receptor, we confirmed that EVT901 interferes with oligomerization of full-length p75 neurotrophin receptor in a dose-dependent manner. Here we report that EVT901 reduces binding of pro-nerve growth factor to p75 neurotrophin receptor, blocks pro-nerve growth factor induced apoptosis in cells expressing p75 neurotrophin receptor, and enhances neurite outgrowth in vitro. Furthermore, we demonstrate that EVT901 abrogates p75 neurotrophin receptor signalling by other ligands, such as prion peptide and amyloid-β. To test the efficacy of EVT901 in vivo, we evaluated the outcome in two models of traumatic brain injury. We generated controlled cortical impacts in adult rats. Using unbiased stereological analysis, we found that EVT901 delivered intravenously daily for 1 week after injury, reduced lesion size, protected cortical neurons and oligodendrocytes, and had a positive effect on neurological function. After lateral fluid percussion injury in adult rats, oral treatment with EVT901 reduced neuronal death in the hippocampus and thalamus, reduced long-term cognitive deficits, and reduced the occurrence of post-traumatic seizure activity. Together, these studies provide a new reagent for altering p75 neurotrophin receptor actions after injury and suggest that EVT901 may be useful in treatment of central nervous system trauma and other neurological disorders where p75 neurotrophin receptor signalling is affected.
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Affiliation(s)
| | - Sangmi Lee
- 2 Brain and Spinal Injury Center, Department of Neurological Surgery, University of California, San Francisco, 1001 Potrero Ave, San Francisco, CA 94110, USA
| | - Marco Baroni
- 3 Sanofi Research, Exploratory Unit, Via Gaetano Sbodio 2, 20134 Milano, Italy
| | - Isabelle Lamarche
- 4 From Sanofi Research, Early to Candidate, 195 route d'Espagne, 31036 Toulouse cedex, France
| | - Michele Arnone
- 4 From Sanofi Research, Early to Candidate, 195 route d'Espagne, 31036 Toulouse cedex, France
| | - Benoit Canolle
- 4 From Sanofi Research, Early to Candidate, 195 route d'Espagne, 31036 Toulouse cedex, France
| | - Amity Lin
- 2 Brain and Spinal Injury Center, Department of Neurological Surgery, University of California, San Francisco, 1001 Potrero Ave, San Francisco, CA 94110, USA
| | - Jeffrey Sacramento
- 2 Brain and Spinal Injury Center, Department of Neurological Surgery, University of California, San Francisco, 1001 Potrero Ave, San Francisco, CA 94110, USA
| | - Ernesto A Salegio
- 2 Brain and Spinal Injury Center, Department of Neurological Surgery, University of California, San Francisco, 1001 Potrero Ave, San Francisco, CA 94110, USA
| | - Marie-Noelle Castel
- 4 From Sanofi Research, Early to Candidate, 195 route d'Espagne, 31036 Toulouse cedex, France
| | | | - Antoine Alam
- 4 From Sanofi Research, Early to Candidate, 195 route d'Espagne, 31036 Toulouse cedex, France
| | - Patricia Laboudie
- 4 From Sanofi Research, Early to Candidate, 195 route d'Espagne, 31036 Toulouse cedex, France
| | - Badia Ferzaz
- 4 From Sanofi Research, Early to Candidate, 195 route d'Espagne, 31036 Toulouse cedex, France
| | - Pierre Savi
- 4 From Sanofi Research, Early to Candidate, 195 route d'Espagne, 31036 Toulouse cedex, France
| | - Jean-Marc Herbert
- 4 From Sanofi Research, Early to Candidate, 195 route d'Espagne, 31036 Toulouse cedex, France
| | - Geoffrey T Manley
- 2 Brain and Spinal Injury Center, Department of Neurological Surgery, University of California, San Francisco, 1001 Potrero Ave, San Francisco, CA 94110, USA
| | - Adam R Ferguson
- 2 Brain and Spinal Injury Center, Department of Neurological Surgery, University of California, San Francisco, 1001 Potrero Ave, San Francisco, CA 94110, USA
| | - Jacqueline C Bresnahan
- 2 Brain and Spinal Injury Center, Department of Neurological Surgery, University of California, San Francisco, 1001 Potrero Ave, San Francisco, CA 94110, USA
| | - Françoise Bono
- 1 Evotec, 195 route d'Espagne, 31036 Toulouse cedex, France
| | - Michael S Beattie
- 2 Brain and Spinal Injury Center, Department of Neurological Surgery, University of California, San Francisco, 1001 Potrero Ave, San Francisco, CA 94110, USA
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33
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Nadezhdin KD, García-Carpio I, Goncharuk SA, Mineev KS, Arseniev AS, Vilar M. Structural Basis of p75 Transmembrane Domain Dimerization. J Biol Chem 2016; 291:12346-57. [PMID: 27056327 DOI: 10.1074/jbc.m116.723585] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Indexed: 12/14/2022] Open
Abstract
Dimerization of single span transmembrane receptors underlies their mechanism of activation. p75 neurotrophin receptor plays an important role in the nervous system, but the understanding of p75 activation mechanism is still incomplete. The transmembrane (TM) domain of p75 stabilizes the receptor dimers through a disulfide bond, essential for the NGF signaling. Here we solved by NMR the three-dimensional structure of the p75-TM-WT and the functionally inactive p75-TM-C257A dimers. Upon reconstitution in lipid micelles, p75-TM-WT forms the disulfide-linked dimers spontaneously. Under reducing conditions, p75-TM-WT is in a monomer-dimer equilibrium with the Cys(257) residue located on the dimer interface. In contrast, p75-TM-C257A forms dimers through the AXXXG motif on the opposite face of the α-helix. Biochemical and cross-linking experiments indicate that AXXXG motif is not on the dimer interface of p75-TM-WT, suggesting that the conformation of p75-TM-C257A may be not functionally relevant. However, rather than mediating p75 homodimerization, mutagenesis of the AXXXG motif reveals its functional role in the regulated intramembrane proteolysis of p75 catalyzed by the γ-secretase complex. Our structural data provide an insight into the key role of the Cys(257) in stabilization of the weak transmembrane dimer in a conformation required for the NGF signaling.
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Affiliation(s)
- Kirill D Nadezhdin
- From the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow 117997, Russian Federation and
| | - Irmina García-Carpio
- Neurodegeneration Unit, Unidad Funcional de Investigación de Enfermedades Crónicas-Instituto de Salud Carlos III, Crta Majadahonda a Pozuelo km.2 Majadahonda, Madrid 28220, Spain
| | - Sergey A Goncharuk
- From the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow 117997, Russian Federation and
| | - Konstantin S Mineev
- From the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow 117997, Russian Federation and
| | - Alexander S Arseniev
- From the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow 117997, Russian Federation and
| | - Marçal Vilar
- Neurodegeneration Unit, Unidad Funcional de Investigación de Enfermedades Crónicas-Instituto de Salud Carlos III, Crta Majadahonda a Pozuelo km.2 Majadahonda, Madrid 28220, Spain
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Lin Z, Tann JY, Goh ETH, Kelly C, Lim KB, Gao JF, Ibanez CF. Structural basis of death domain signaling in the p75 neurotrophin receptor. eLife 2015; 4:e11692. [PMID: 26646181 PMCID: PMC4739766 DOI: 10.7554/elife.11692] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2015] [Accepted: 12/06/2015] [Indexed: 12/30/2022] Open
Abstract
Death domains (DDs) mediate assembly of oligomeric complexes for activation of downstream signaling pathways through incompletely understood mechanisms. Here we report structures of complexes formed by the DD of p75 neurotrophin receptor (p75NTR) with RhoGDI, for activation of the RhoA pathway, with caspase recruitment domain (CARD) of RIP2 kinase, for activation of the NF-kB pathway, and with itself, revealing how DD dimerization controls access of intracellular effectors to the receptor. RIP2 CARD and RhoGDI bind to p75NTR DD at partially overlapping epitopes with over 100-fold difference in affinity, revealing the mechanism by which RIP2 recruitment displaces RhoGDI upon ligand binding. The p75NTR DD forms non-covalent, low-affinity symmetric dimers in solution. The dimer interface overlaps with RIP2 CARD but not RhoGDI binding sites, supporting a model of receptor activation triggered by separation of DDs. These structures reveal how competitive protein-protein interactions orchestrate the hierarchical activation of downstream pathways in non-catalytic receptors. DOI:http://dx.doi.org/10.7554/eLife.11692.001 Cells have proteins called receptors on their surface that can bind to specific molecules on the outside of the cell. Typically, this binding activates the receptor and the activated receptor then triggers some biochemical changes inside the cell. For many receptors, the portion of the receptor inside the cell is essentially an enzyme that can trigger a biochemical change by itself. Some receptors, however, lack any enzymatic activity, and it is often unclear how these ‘non-catalytic receptors’ trigger changes inside a cell. A protein called p75 neurotrophin receptor (or p75NTR for short) is a non-catalytic receptor that is expressed when neurons are injured and its activity leads to the death of the neurons and related cells. Inhibiting this non-catalytic receptor is an attractive strategy for limiting the damage caused by diseases of the nervous system. However, the molecular mechanisms behind the activity of p75NTR are not well understood. Previous biochemical studies set out to answer the question of how p75NTR engages with components of the signaling machinery inside the cell, and found several components that interact with this receptor. Now, Lin et al. have tried to gain a more detailed understanding of those interactions at a molecular level. This involved solving the three-dimensional structures of three protein complexes that involve part of p75NTR (called the “death domain”) and one of two signaling components (called RhoGDI and RIP2). Two of the protein complexes showed that RIP2 and RhoGDI bind to the receptor’s death domain at partially overlapping sites, although RIP2 binds about 100 times more strongly than RhoGDI.A third protein complex showed an interaction between two copies of the death domain, which involves a surface of the receptor that overlaps with RIP2’s, but not RhoGDI’s, binding site. These structures, together with the results of other experiments, allowed Lin et al. to propose a model that could explain how p75NTR is activated. First, the two death domains must be separated. Next, RIP2 is recruited to the receptor, and outcompetes and displaces RhoGDI. This change in protein-protein interactions switches the receptor’s signaling from one pathway to the other. Now that these structures are available, they can be used in future experiments to design specific changes in the receptor that would allow researchers to dissect its different activities. DOI:http://dx.doi.org/10.7554/eLife.11692.002
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Affiliation(s)
- Zhi Lin
- Department of Physiology, National University of Singapore, Singapore, Singapore.,Life Sciences Institute, National University of Singapore, Singapore, Singapore
| | - Jason Y Tann
- Department of Physiology, National University of Singapore, Singapore, Singapore.,Life Sciences Institute, National University of Singapore, Singapore, Singapore
| | - Eddy T H Goh
- Department of Physiology, National University of Singapore, Singapore, Singapore.,Life Sciences Institute, National University of Singapore, Singapore, Singapore
| | - Claire Kelly
- Department of Neuroscience, Karolinska Institute, Stockholm, Sweden
| | - Kim Buay Lim
- Department of Physiology, National University of Singapore, Singapore, Singapore.,Life Sciences Institute, National University of Singapore, Singapore, Singapore
| | - Jian Fang Gao
- Department of Physiology, National University of Singapore, Singapore, Singapore.,Life Sciences Institute, National University of Singapore, Singapore, Singapore
| | - Carlos F Ibanez
- Department of Physiology, National University of Singapore, Singapore, Singapore.,Life Sciences Institute, National University of Singapore, Singapore, Singapore.,Department of Neuroscience, Karolinska Institute, Stockholm, Sweden
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