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Staib-Lasarzik I, Gölz C, Bobkiewiecz W, Somnuke P, Sebastiani A, Thal SC, Schäfer MK. Sortilin is dispensable for secondary injury processes following traumatic brain injury in mice. Heliyon 2024; 10:e35198. [PMID: 39170542 PMCID: PMC11336488 DOI: 10.1016/j.heliyon.2024.e35198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 07/15/2024] [Accepted: 07/24/2024] [Indexed: 08/23/2024] Open
Abstract
Traumatic brain injury (TBI) is characterized by complex secondary injury processes involving the p75 neurotrophin receptor (p75NTR), which has been proposed as a possible therapeutic target. However, the pathogenic role of the p75NTR co-receptor sortilin in TBI has not been investigated. In this study, we examined whether sortilin contributes to acute and early processes of secondary injury using a murine controlled cortical impact (CCI) model of TBI. Initial expression analysis showed a down-regulation of sortilin mRNA levels 1 and 5 day post injury (dpi) and a reduced expression of sortilin protein 1 dpi. Next, a total of 40 SortilinΔExon14 loss-of-function mouse mutants (Sort1-/-) and wild-type (Sort1+/+) littermate mice were subjected to CCI and examined at 1 and 5 dpi. Neither sensorimotor deficits or brain lesion size nor CCI-induced cell death or calcium-dependent excitotoxicity as evaluated by TUNEL staining or Western blot analysis of alpha II spectrin breakdown products were different between Sort1-/- and Sort1+/+ mice. In addition, CCI induced the up-regulation of pro-inflammatory marker mRNA expression (Il6, Tnfa, Aif1, and Gfap) irrespectively of the genotype. Similarly, the mRNA expressions of neurotrophins (Bdnf, Ngf, Nt3), VPS10P domain receptors others than sortilin (Ngfr, Sorl1, Sorcs2), and the sortilin interactor progranulin were not affected by genotype. Our results suggest that sortilin is a modulatory rather than a critical factor in the acute and early brain tissue response after TBI.
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Affiliation(s)
- Irina Staib-Lasarzik
- Department of Anesthesiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Christina Gölz
- Department of Anesthesiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Wieslawa Bobkiewiecz
- Department of Anesthesiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Pawit Somnuke
- Department of Anesthesiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
| | - Anne Sebastiani
- Department of Anesthesiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Serge C. Thal
- Department of Anesthesiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Michael K.E. Schäfer
- Department of Anesthesiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
- Focus Program Translational Neurosciences (FTN) of the Johannes Gutenberg-University Mainz, Mainz, Germany
- Research Center for Immunotherapy, University Medical Center, Johannes Gutenberg-University Mainz, Mainz, Germany
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2
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Hino M, Nakanishi M, Nomoto H. The expression system affects the binding affinity between p75NTR and proNGF. Biochem Biophys Rep 2024; 38:101702. [PMID: 38596407 PMCID: PMC11001769 DOI: 10.1016/j.bbrep.2024.101702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 03/13/2024] [Accepted: 03/28/2024] [Indexed: 04/11/2024] Open
Abstract
ProNGF (nerve growth factor) is a precursor of NGF and a signaling peptide exerting opposite effects on neuronal cells, i.e., apoptotic or neuritogenic. The conflicting biological activity of proNGF depends on the relative levels of two membrane receptors, TrkA and p75NTR. The effect of proNGF depends on the expression levels of these receptor proteins and their affinity to proNGF. Since the affinity of proteins has been studied with various recombinant proteins, it is worth comparing the affinity of these proteins within one experiment with the same method. This study examined the affinity between a recombinant proNGF and p75NTR expressed in common systems: bacterial, insect, and mammalian cells. The extracellular domain of p75NTR expressed in the insect or mammalian systems bound to native mature NGF, with a higher affinity for the insect receptor. The uncleavable proNGF was expressed in the three systems and they showed neuritogenic activity in PC12 cells. These recombinant proteins were used to compare their binding affinity to p75NTR. The insect p75NTR showed a higher binding affinity to proNGF than the mammalian p75NTR. The insect p75NTR bound proNGF from the insect system with the highest affinity, then from the mammalian system, and the lowest from the bacterial system. Conversely, the mammalian p75NTR showed no such preference for proNGF. Because the recombinant proNGF and p75NTR from different expression systems are supposed to have the same amino acid sequences, these differences in the affinity depend likely on their post-translational modifications, most probably on their glycans. Each recombinant proNGF and p75NTR in various expression systems exhibited different mobilities on SDS-PAGE and reactivities with glycosidases and lectins.
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Affiliation(s)
- Mami Hino
- Laboratory of Biochemistry, School of Pharmaceutical Sciences, Matsuyama University, Matsuyama, Ehime, 790-8578, Japan
| | - Masayuki Nakanishi
- Laboratory of Biochemistry, School of Pharmaceutical Sciences, Matsuyama University, Matsuyama, Ehime, 790-8578, Japan
| | - Hiroshi Nomoto
- Laboratory of Biochemistry, School of Pharmaceutical Sciences, Matsuyama University, Matsuyama, Ehime, 790-8578, Japan
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3
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Makoudjou MA, Fico E, Rosso P, Triaca V, De Simone L, Rossetti D, Cattani F, Allegretti M, Tirassa P. ProNGF processing in adult rat tissues and bioactivity of NGF prodomain peptides. FEBS Open Bio 2024; 14:643-654. [PMID: 38429912 PMCID: PMC10988682 DOI: 10.1002/2211-5463.13768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 11/23/2023] [Accepted: 01/11/2024] [Indexed: 03/03/2024] Open
Abstract
The neurotrophin nerve growth factor (NGF) and its precursor proNGF are both bioactive and exert similar or opposite actions depending on the cell target and its milieu. The balance between NGF and proNGF is crucial for cell and tissue homeostasis and it is considered an indicator of pathological conditions. Proteolytical cleavage of proNGF to the mature form results in different fragments, whose function and/or bioactivity is still unclear. The present study was conducted to investigate the distribution of proNGF fragments derived from endogenous cleavage in brain and peripheral tissues of adult rats in the healthy condition and following inflammatory lipopolysaccharide (LPS) challenge. Different anti-proNGF antibodies were tested and the presence of short peptides corresponding to the prodomain sequence (pdNGFpep) was identified. Processing of proNGF was found to be tissue-specific and accumulation of pdNGFpeps was found in inflamed tissues, mainly in testis, intestine and heart, suggesting a possible correlation between organ functions and a response to insults and/or injury. The bioactivity of pdNGFpep was also demonstrated in vitro by using primary hippocampal neurons. Our study supports a biological function for the NGF precursor prodomain and indicates that short peptides from residues 1-60, differing from the 70-110 sequence, induce apoptosis, thereby opening the way for identification of new molecular targets to study pathological conditions.
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Affiliation(s)
- Marie Anne Makoudjou
- Cellular and Molecular Biology, Department of BiologyUniversity of Rome “Tor Vergata”RomeItaly
- Institute of Biochemistry and Cell Biology (IBBC)National Research Council (CNR)RomeItaly
| | - Elena Fico
- Institute of Biochemistry and Cell Biology (IBBC)National Research Council (CNR)RomeItaly
| | - Pamela Rosso
- Institute of Biochemistry and Cell Biology (IBBC)National Research Council (CNR)RomeItaly
| | - Viviana Triaca
- Institute of Biochemistry and Cell Biology (IBBC)National Research Council (CNR)Campus A. Buzzati‐Traverso, MonterotondoRomeItaly
| | | | | | | | | | - Paola Tirassa
- Institute of Biochemistry and Cell Biology (IBBC)National Research Council (CNR)RomeItaly
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4
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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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5
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Covaceuszach S, Lamba D. The NGF R100W Mutation, Associated with Hereditary Sensory Autonomic Neuropathy Type V, Specifically Affects the Binding Energetic Landscapes of NGF and of Its Precursor proNGF and p75NTR. BIOLOGY 2023; 12:biology12030364. [PMID: 36979056 PMCID: PMC10045213 DOI: 10.3390/biology12030364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 02/20/2023] [Accepted: 02/23/2023] [Indexed: 03/03/2023]
Abstract
Nerve Growth Factor (NGF), the prototype of the neurotrophin family, stimulates morphological differentiation and regulates neuronal gene expression by binding to TrkA and p75NTR receptors. It plays a critical role in maintaining the function and phenotype of peripheral sensory and sympathetic neurons and in mediating pain transmission and perception during adulthood. A point mutation in the NGFB gene (leading to the amino acid substitution R100W) is responsible for Hereditary Sensory and Autonomic Neuropathy type V (HSAN V), leading to a congenital pain insensitivity with no clear cognitive impairments, but with alterations in the NGF/proNGF balance. The available crystal structures of the p75NTR/NGF and 2p75NTR/proNGF complexes offer a starting point for Molecular Dynamics (MD) simulations in order to capture the impact of the R100W mutation on their binding energetic landscapes and to unveil the molecular determinants that trigger their different physiological and pathological outcomes. The present in silico studies highlight that the stability and the binding energetic fingerprints in the 2p75NTR/proNGF complex is not affected by R100W mutation, which on the contrary, deeply affects the energetic landscape, and thus the stability in the p75NTR/NGF complex. Overall, these findings present insights into the structural basis of the molecular mechanisms beyond the clinical manifestations of HSAN V patients.
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Affiliation(s)
- Sonia Covaceuszach
- Istituto di Cristallografia, Consiglio Nazionale delle Ricerche, 34149 Trieste, Italy
- Correspondence: (S.C.); (D.L.)
| | - Doriano Lamba
- Istituto di Cristallografia, Consiglio Nazionale delle Ricerche, 34149 Trieste, Italy
- Consorzio Interuniversitario “Istituto Nazionale Biostrutture e Biosistemi”, 00136 Roma, Italy
- Correspondence: (S.C.); (D.L.)
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6
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Paoletti F, Covaceuszach S, Cassetta A, Calabrese AN, Novak U, Konarev P, Grdadolnik J, Lamba D, Golič Grdadolnik S. Distinct conformational changes occur within the intrinsically unstructured pro-domain of pro-Nerve Growth Factor in the presence of ATP and Mg 2. Protein Sci 2023; 32:e4563. [PMID: 36605018 PMCID: PMC9878617 DOI: 10.1002/pro.4563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 11/24/2022] [Accepted: 01/03/2023] [Indexed: 01/07/2023]
Abstract
Nerve growth factor (NGF), the prototypical neurotrophic factor, is involved in the maintenance and growth of specific neuronal populations, whereas its precursor, proNGF, is involved in neuronal apoptosis. Binding of NGF or proNGF to TrkA, p75NTR , and VP10p receptors triggers complex intracellular signaling pathways that can be modulated by endogenous small-molecule ligands. Here, we show by isothermal titration calorimetry and NMR that ATP binds to the intrinsically disordered pro-peptide of proNGF with a micromolar dissociation constant. We demonstrate that Mg2+ , known to play a physiological role in neurons, modulates the ATP/proNGF interaction. An integrative structural biophysics analysis by small angle X-ray scattering and hydrogen-deuterium exchange mass spectrometry unveils that ATP binding induces a conformational rearrangement of the flexible pro-peptide domain of proNGF. This suggests that ATP may act as an allosteric modulator of the overall proNGF conformation, whose likely distinct biological activity may ultimately affect its physiological homeostasis.
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Affiliation(s)
- Francesca Paoletti
- Laboratory for Molecular Structural Dynamics, Theory DepartmentNational Institute of ChemistryLjubljanaSlovenia
| | | | - Alberto Cassetta
- Institute of Crystallography—C.N.R.—Trieste OutstationTriesteItaly
| | - Antonio N. Calabrese
- School of Molecular and Cellular Biology, Astbury Centre for Structural Molecular BiologyUniversity of LeedsLeedsUK
| | - Urban Novak
- Laboratory for Molecular Structural Dynamics, Theory DepartmentNational Institute of ChemistryLjubljanaSlovenia
| | - Petr Konarev
- A.V. Shubnikov Institute of Crystallography of Federal Scientific Research Centre “Crystallography and Photonics”Russian Academy of SciencesMoscowRussia
| | - Jože Grdadolnik
- Laboratory for Molecular Structural Dynamics, Theory DepartmentNational Institute of ChemistryLjubljanaSlovenia
| | - Doriano Lamba
- Institute of Crystallography—C.N.R.—Trieste OutstationTriesteItaly
- Interuniversity Consortium “Biostructures and Biosystems National Institute”RomeItaly
| | - Simona Golič Grdadolnik
- Laboratory for Molecular Structural Dynamics, Theory DepartmentNational Institute of ChemistryLjubljanaSlovenia
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7
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Mitok KA, Keller MP, Attie AD. Sorting through the extensive and confusing roles of sortilin in metabolic disease. J Lipid Res 2022; 63:100243. [PMID: 35724703 PMCID: PMC9356209 DOI: 10.1016/j.jlr.2022.100243] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 06/10/2022] [Accepted: 06/13/2022] [Indexed: 01/06/2023] Open
Abstract
Sortilin is a post-Golgi trafficking receptor homologous to the yeast vacuolar protein sorting receptor 10 (VPS10). The VPS10 motif on sortilin is a 10-bladed β-propeller structure capable of binding more than 50 proteins, covering a wide range of biological functions including lipid and lipoprotein metabolism, neuronal growth and death, inflammation, and lysosomal degradation. Sortilin has a complex cellular trafficking itinerary, where it functions as a receptor in the trans-Golgi network, endosomes, secretory vesicles, multivesicular bodies, and at the cell surface. In addition, sortilin is associated with hypercholesterolemia, Alzheimer's disease, prion diseases, Parkinson's disease, and inflammation syndromes. The 1p13.3 locus containing SORT1, the gene encoding sortilin, carries the strongest association with LDL-C of all loci in human genome-wide association studies. However, the mechanism by which sortilin influences LDL-C is unclear. Here, we review the role sortilin plays in cardiovascular and metabolic diseases and describe in detail the large and often contradictory literature on the role of sortilin in the regulation of LDL-C levels.
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Affiliation(s)
- Kelly A Mitok
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Mark P Keller
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Alan D Attie
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA.
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8
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The role of pro-domains in human growth factors and cytokines. Biochem Soc Trans 2021; 49:1963-1973. [PMID: 34495310 PMCID: PMC8589418 DOI: 10.1042/bst20200663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 08/17/2021] [Accepted: 08/19/2021] [Indexed: 11/30/2022]
Abstract
Many growth factors and cytokines are produced as larger precursors, containing pro-domains, that require proteolytic processing to release the bioactive ligand. These pro-domains can be significantly larger than the mature domains and can play an active role in the regulation of the ligands. Mining the UniProt database, we identified almost one hundred human growth factors and cytokines with pro-domains. These are spread across several unrelated protein families and vary in both their size and composition. The precise role of each pro-domain varies significantly between the protein families. Typically they are critical for controlling bioactivity and protein localisation, and they facilitate diverse mechanisms of activation. Significant gaps in our understanding remain for pro-domain function — particularly their fate once the bioactive ligand has been released. Here we provide an overview of pro-domain roles in human growth factors and cytokines, their processing, regulation and activation, localisation as well as therapeutic potential.
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9
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Dedoni S, Marras L, Olianas MC, Ingianni A, Onali P. Valproic acid upregulates the expression of the p75NTR/sortilin receptor complex to induce neuronal apoptosis. Apoptosis 2021; 25:697-714. [PMID: 32712736 PMCID: PMC7527367 DOI: 10.1007/s10495-020-01626-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The antiepileptic and mood stabilizer agent valproic acid (VPA) has been shown to exert anti-tumour effects and to cause neuronal damage in the developing brain through mechanisms not completely understood. In the present study we show that prolonged exposure of SH-SY5Y and LAN-1 human neuroblastoma cells to clinically relevant concentrations of VPA caused a marked induction of the protein and transcript levels of the common neurotrophin receptor p75NTR and its co-receptor sortilin, two promoters of apoptotic cell death in response to proneurotrophins. VPA induction of p75NTR and sortilin was associated with an increase in plasma membrane expression of the receptor proteins and was mimicked by cell treatment with several histone deacetylase (HDAC) inhibitors. VPA and HDAC1 knockdown decreased the level of EZH2, a core component of the polycomb repressive complex 2, and upregulated the transcription factor CASZ1, a positive regulator of p75NTR. CASZ1 knockdown attenuated VPA-induced p75NTR overexpression. Cell treatment with VPA favoured proNGF-induced p75NTR/sortilin interaction and the exposure to proNGF enhanced JNK activation and apoptotic cell death elicited by VPA. Depletion of p75NTR or addition of the sortilin agonist neurotensin to block proNGF/sortilin interaction reduced the apoptotic response to VPA and proNGF. Exposure of mouse cerebellar granule cells to VPA upregulated p75NTR and sortilin and induced apoptosis which was enhanced by proNGF. These results indicate that VPA upregulates p75NTR apoptotic cell signalling through an epigenetic mechanism involving HDAC inhibition and suggest that this effect may contribute to the anti-neuroblastoma and neurotoxic effects of VPA.
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Affiliation(s)
- Simona Dedoni
- Laboratory of Cellular and Molecular Pharmacology, Section of Neurosciences and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, 09042, Monserrato, CA, Italy
| | - Luisa Marras
- Section of Microbiology, Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy
| | - Maria C Olianas
- Laboratory of Cellular and Molecular Pharmacology, Section of Neurosciences and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, 09042, Monserrato, CA, Italy
| | - Angela Ingianni
- Section of Microbiology, Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy
| | - Pierluigi Onali
- Laboratory of Cellular and Molecular Pharmacology, Section of Neurosciences and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, 09042, Monserrato, CA, Italy.
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10
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Dougherty MC, Shibata SB, Hansen MR. The biological underpinnings of radiation therapy for vestibular schwannomas: Review of the literature. Laryngoscope Investig Otolaryngol 2021; 6:458-468. [PMID: 34195368 PMCID: PMC8223465 DOI: 10.1002/lio2.553] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 02/05/2021] [Accepted: 03/12/2021] [Indexed: 12/18/2022] Open
Abstract
OBJECTIVE Radiation therapy is a mainstay in the treatment of numerous neoplasms. Numerous publications have reported good clinical outcomes for primary radiation therapy for Vestibular Schwannomas (VS). However, there are relatively few pathologic specimens of VSs available to evaluate post-radiation, which has led to a relative dearth in research on the cellular mechanisms underlying the effects of radiation therapy on VSs. METHODS Here we review the latest literature on the complex biological effects of radiation therapy on these benign tumors-including resistance to oxidative stress, mechanisms of DNA damage repair, alterations in normal growth factor pathways, changes in surrounding vasculature, and alterations in immune responses following radiation. RESULTS Although VSs are highly radioresistant, radiotherapy is often successful in arresting their growth. CONCLUSION By better understanding the mechanisms underlying these effects, we could potentially harness such mechanisms in the future to potentiate the clinical effects of radiotherapy on VSs. LEVEL OF EVIDENCE N/A.
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Affiliation(s)
- Mark C. Dougherty
- Department of NeurosurgeryUniversity of Iowa Hospitals & ClinicsIowa CityIowaUSA
| | - Seiji B. Shibata
- Department of Otolaryngology, Keck School of Medicine of USCUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Marlan R. Hansen
- Department of Otolaryngology—Head & Neck SurgeryUniversity of Iowa Hospitals & ClinicsIowa CityIowaUSA
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11
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Covaceuszach S, Peche L, Konarev P, Lamba D. A combined evolutionary and structural approach to disclose the primary structural determinants essential for proneurotrophins biological functions. Comput Struct Biotechnol J 2021; 19:2891-2904. [PMID: 34094000 PMCID: PMC8144349 DOI: 10.1016/j.csbj.2021.05.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 05/03/2021] [Accepted: 05/03/2021] [Indexed: 12/24/2022] Open
Abstract
The neurotrophins, i.e., Nerve Growth Factor (NGF), Brain-Derived Neurotrophic Factor (BDNF), Neurotrophin 3 (NT3) and Neurotrophin 4 (NT4), are known to play a range of crucial functions in the developing and adult peripheral and central nervous systems. Initially synthesized as precursors, i.e., proneurotrophins (proNTs), that are cleaved to release C-terminal mature forms, they act through two types of receptors, the specific Trk receptors (Tropomyosin-related kinases) and the pan-neurotrophin receptor p75NTR, to initiate survival and differentiative responses. Recently, all the proNTs but proNT4 have been demonstrated to be not just inactive precursors, but signaling ligands that mediate opposing actions in fundamental aspects of the nervous system with respect to the mature counterparts through dual-receptor complexes formation with a member of the VPS10 family and p75NTR. Despite the functional relevance, the molecular determinants underpinning the interactions between the pro-domains and their receptors are still elusive probably due to their intrinsically disordered nature. Here we present an evolutionary approach coupled to an experimental study aiming to uncover the structural and dynamical basis of the biological function displayed by proNGF, proBDNF and proNT3 but missing in proNT4. A bioinformatic analysis allowed to elucidate the functional adaptability of the proNTs family in vertebrates, identifying conserved key structural features. The combined biochemical and SAXS experiments shed lights on the structure and dynamic behavior of the human proNTs in solution, giving insights on the evolutionary conserved structural motifs, essential for the multifaceted roles of proNTs in physiological as well as in pathological contexts.
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Affiliation(s)
- S. Covaceuszach
- Istituto di Cristallografia, Consiglio Nazionale delle Ricerche, Trieste, Italy
| | - L.Y. Peche
- Istituto di Cristallografia, Consiglio Nazionale delle Ricerche, Trieste, Italy
| | - P.V. Konarev
- A.V. Shubnikov Institute of Crystallography of Federal Scientific Research Centre “Crystallography and Photonics” of Russian Academy of Sciences, Moscow, Russia
| | - D. Lamba
- Istituto di Cristallografia, Consiglio Nazionale delle Ricerche, Trieste, Italy
- Interuniversity Consortium “Biostructures and Biosystems National Institute”, Roma, Italy
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12
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Li A, Feng L, Niu X, Zeng Q, Li B, You Z. Downregulation of OIP5-AS1 affects proNGF-induced pancreatic cancer metastasis by inhibiting p75NTR levels. Aging (Albany NY) 2021; 13:10688-10702. [PMID: 33820868 PMCID: PMC8064169 DOI: 10.18632/aging.202847] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 09/28/2020] [Indexed: 02/06/2023]
Abstract
We aimed to explore the mechanism by which long non-coding RNA (lncRNA) OIP5-AS1 affects proNGF (precursor nerve growth factor)-induced pancreatic cancer metastasis by targeting the miR-186-5p/NGFR axis. Bioinformatics was used to analyse whether OIP5-AS1 targets miR-186-5p/NGFR and their expression characteristics in pancreatic cancer. OIP5-AS1 and NGFR were overexpressed in pancreatic cancer, and their levels showed a significant positive correlation. Clinical trials also demonstrated that high expression of OIP5-AS1 and NGFR and low expression of miR-186-5p played a pro-cancer role in pancreatic cancer. MiR-186-5p inhibited the migration and invasion of colon cancer cells by targeting NGFR-regulated p75NTR. OIP5-AS1 regulated the action of miR-186-5p on NGFR mRNA and p75NTR by targeting miR-186-5p. Downregulation of NGFR inhibited the expression of p75NTR protein and blocked the role of proNGF in promoting the migration and invasion of pancreatic cancer cells. Animal experiments also showed that the knockdown of miR-186-5p promoted cancer via the expression of NGFR mRNA and p75NTR protein, while the downregulation of proNGF blocked the effects. OIP5-AS1, as a ceRNA, promotes the progression of pancreatic cancer by targeting miR-186-5p/NGFR and affecting the prognosis of patients, which may be related to the action of proNGF.
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Affiliation(s)
- Ang Li
- Department of Pancreatic Surgery, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Lei Feng
- Department of Biliary Surgery, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Xiaoya Niu
- Department of Biliary Surgery, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Qihui Zeng
- Department of Biliary Surgery, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Bei Li
- Department of Biliary Surgery, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Zhen You
- Department of Biliary Surgery, West China Hospital of Sichuan University, Chengdu 610041, China
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Ozalp O, Cark O, Azbazdar Y, Haykir B, Cucun G, Kucukaylak I, Alkan-Yesilyurt G, Sezgin E, Ozhan G. Nradd Acts as a Negative Feedback Regulator of Wnt/β-Catenin Signaling and Promotes Apoptosis. Biomolecules 2021; 11:100. [PMID: 33466728 PMCID: PMC7828832 DOI: 10.3390/biom11010100] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 01/05/2021] [Accepted: 01/11/2021] [Indexed: 12/16/2022] Open
Abstract
Wnt/β-catenin signaling controls many biological processes for the generation and sustainability of proper tissue size, organization and function during development and homeostasis. Consequently, mutations in the Wnt pathway components and modulators cause diseases, including genetic disorders and cancers. Targeted treatment of pathway-associated diseases entails detailed understanding of the regulatory mechanisms that fine-tune Wnt signaling. Here, we identify the neurotrophin receptor-associated death domain (Nradd), a homolog of p75 neurotrophin receptor (p75NTR), as a negative regulator of Wnt/β-catenin signaling in zebrafish embryos and in mammalian cells. Nradd significantly suppresses Wnt8-mediated patterning of the mesoderm and neuroectoderm during zebrafish gastrulation. Nradd is localized at the plasma membrane, physically interacts with the Wnt receptor complex and enhances apoptosis in cooperation with Wnt/β-catenin signaling. Our functional analyses indicate that the N-glycosylated N-terminus and the death domain-containing C-terminus regions are necessary for both the inhibition of Wnt signaling and apoptosis. Finally, Nradd can induce apoptosis in mammalian cells. Thus, Nradd regulates cell death as a modifier of Wnt/β-catenin signaling during development.
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Affiliation(s)
- Ozgun Ozalp
- Izmir Biomedicine and Genome Center (IBG), Dokuz Eylul University Health Campus, Inciralti-Balcova, 35340 Izmir, Turkey; (O.O.); (O.C.); (Y.A.); (B.H.); (G.C.); (I.K.); (G.A.-Y.)
- Izmir International Biomedicine and Genome Institute (IBG-Izmir), Dokuz Eylul University, Inciralti-Balcova, 35340 Izmir, Turkey
| | - Ozge Cark
- Izmir Biomedicine and Genome Center (IBG), Dokuz Eylul University Health Campus, Inciralti-Balcova, 35340 Izmir, Turkey; (O.O.); (O.C.); (Y.A.); (B.H.); (G.C.); (I.K.); (G.A.-Y.)
- Izmir International Biomedicine and Genome Institute (IBG-Izmir), Dokuz Eylul University, Inciralti-Balcova, 35340 Izmir, Turkey
| | - Yagmur Azbazdar
- Izmir Biomedicine and Genome Center (IBG), Dokuz Eylul University Health Campus, Inciralti-Balcova, 35340 Izmir, Turkey; (O.O.); (O.C.); (Y.A.); (B.H.); (G.C.); (I.K.); (G.A.-Y.)
- Izmir International Biomedicine and Genome Institute (IBG-Izmir), Dokuz Eylul University, Inciralti-Balcova, 35340 Izmir, Turkey
| | - Betul Haykir
- Izmir Biomedicine and Genome Center (IBG), Dokuz Eylul University Health Campus, Inciralti-Balcova, 35340 Izmir, Turkey; (O.O.); (O.C.); (Y.A.); (B.H.); (G.C.); (I.K.); (G.A.-Y.)
- Institute of Physiology, Switzerland and National Center of Competence in Research NCCR Kidney, University of Zurich, CH-8057 Zurich, Switzerland
| | - Gokhan Cucun
- Izmir Biomedicine and Genome Center (IBG), Dokuz Eylul University Health Campus, Inciralti-Balcova, 35340 Izmir, Turkey; (O.O.); (O.C.); (Y.A.); (B.H.); (G.C.); (I.K.); (G.A.-Y.)
- Izmir International Biomedicine and Genome Institute (IBG-Izmir), Dokuz Eylul University, Inciralti-Balcova, 35340 Izmir, Turkey
| | - Ismail Kucukaylak
- Izmir Biomedicine and Genome Center (IBG), Dokuz Eylul University Health Campus, Inciralti-Balcova, 35340 Izmir, Turkey; (O.O.); (O.C.); (Y.A.); (B.H.); (G.C.); (I.K.); (G.A.-Y.)
- Institute of Zoology-Developmental Biology, University of Cologne, 50674 Cologne, Germany
| | - Gozde Alkan-Yesilyurt
- Izmir Biomedicine and Genome Center (IBG), Dokuz Eylul University Health Campus, Inciralti-Balcova, 35340 Izmir, Turkey; (O.O.); (O.C.); (Y.A.); (B.H.); (G.C.); (I.K.); (G.A.-Y.)
| | - Erdinc Sezgin
- Science for Life Laboratory, Department of Women’s and Children’s Health, Karolinska Institutet, 17177 Stockholm, Sweden;
- MRC Weatherall Institute of Molecular Medicine, MRC Human Immunology Unit, University of Oxford, Oxford OX39DS, UK
| | - Gunes Ozhan
- Izmir Biomedicine and Genome Center (IBG), Dokuz Eylul University Health Campus, Inciralti-Balcova, 35340 Izmir, Turkey; (O.O.); (O.C.); (Y.A.); (B.H.); (G.C.); (I.K.); (G.A.-Y.)
- Izmir International Biomedicine and Genome Institute (IBG-Izmir), Dokuz Eylul University, Inciralti-Balcova, 35340 Izmir, Turkey
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Fang J, Wei Z, Zheng D, Ying T, Hong H, Hu D, Lin Y, Jiang X, Wu L, Lan T, Yang Z, Zhou X, Chen L. Recombinant Extracellular Domain (p75ECD) of the Neurotrophin Receptor p75 Attenuates Myocardial Ischemia-Reperfusion Injury by Inhibiting the p-JNK/Caspase-3 Signaling Pathway in Rat Microvascular Pericytes. J Am Heart Assoc 2020; 9:e016047. [PMID: 32567476 PMCID: PMC7670530 DOI: 10.1161/jaha.119.016047] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Background Pro-NTs (precursor of neurotrophins) and their receptor p75 are potential targets for preventing microvascular dysfunction induced by myocardial ischemia-reperfusion injury (IRI). p75ECD (ectodomain of neurotrophin receptor p75) may physiologically produce neurocytoprotective effects by scavenging pro-NTs. We therefore hypothesized that p75ECD may have a cardioprotective effect on IRI through microvascular mechanisms. Methods and Results Myocardial IRI was induced in Sprague-Dawley rats by occluding the left main coronary arteries for 45 minutes before a subsequent relaxation. Compared with the ischemia-reperfusion group, an intravenous injection of p75ECD (3 mg/kg) 5 minutes before reperfusion reduced the myocardial infarct area at 24 hours after reperfusion (by triphenyltetrazolium chloride, 44.9±3.9% versus 34.6±5.7%, P<0.05); improved the left ventricular ejection fraction (by echocardiography), with less myocardial fibrosis (by Masson's staining), and prevented microvascular dysfunction (by immunofluorescence) at 28 days after reperfusion; and reduced myocardial pro-NTs expression at 24 hours and 28 days after reperfusion (by Western blotting). A simulative IRI model using rat microvascular pericytes was established in vitro by hypoxia-reoxygenation (2/6 hours) combined with pro-NTs treatment (3 nmol/L) at R. p75ECD (3 μg/mL) given at R improved pericyte survival (by methyl thiazolyl tetrazolium assay) and attenuated apoptosis (by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling). In the reperfused hearts and hypoxia-reoxygenation +pro-NTs-injured pericytes, p75ECD inhibited the expression of p-JNK (phospho of c-Jun N-terminal kinase)/caspase-3 (by Western blotting). SP600125, an inhibitor of JNK, did not enhance the p75ECD-induced infarct-sparing effects and pericyte protection. Conclusions p75ECD may attenuate myocardial IRI via pro-NTs reduction-induced inhibition of p-JNK/caspase-3 pathway of microvascular pericytes in rats.
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Affiliation(s)
- Jun Fang
- Department of Cardiology Fujian Heart Medical Center Fujian Institute of Coronary Heart Disease Fujian Medical University Union Hospital Fuzhou P. R. China
| | - ZhiXiong Wei
- Department of Cardiology Fujian Heart Medical Center Fujian Institute of Coronary Heart Disease Fujian Medical University Union Hospital Fuzhou P. R. China
| | - DeDong Zheng
- Department of Cardiology Fujian Heart Medical Center Fujian Institute of Coronary Heart Disease Fujian Medical University Union Hospital Fuzhou P. R. China
| | - Teng Ying
- Department of Cardiology Fujian Heart Medical Center Fujian Institute of Coronary Heart Disease Fujian Medical University Union Hospital Fuzhou P. R. China
| | - HuaShan Hong
- Fujian Key Laboratory of Vascular Aging Department of Geriatrics Fujian Institute of Geriatrics Fujian Medical University Union Hospital Fuzhou P. R. China
| | - DanQing Hu
- Department of Cardiology Fujian Heart Medical Center Fujian Institute of Coronary Heart Disease Fujian Medical University Union Hospital Fuzhou P. R. China
| | - YunLing Lin
- Department of Cardiology Fujian Heart Medical Center Fujian Institute of Coronary Heart Disease Fujian Medical University Union Hospital Fuzhou P. R. China
| | - XiaoLiang Jiang
- Institute of Laboratory Animal Science Chinese Academy of Medical Sciences & Comparative Medicine Centre, Peking Union Medical Collage, and Beijing Collaborative Innovation Center for Cardiovascular Disorders Beijing P. R. China
| | - LingZhen Wu
- Department of Cardiology Fujian Heart Medical Center Fujian Institute of Coronary Heart Disease Fujian Medical University Union Hospital Fuzhou P. R. China
| | - TingXiang Lan
- Department of Cardiology Fujian Heart Medical Center Fujian Institute of Coronary Heart Disease Fujian Medical University Union Hospital Fuzhou P. R. China
| | - ZhiWei Yang
- Institute of Laboratory Animal Science Chinese Academy of Medical Sciences & Comparative Medicine Centre, Peking Union Medical Collage, and Beijing Collaborative Innovation Center for Cardiovascular Disorders Beijing P. R. China
| | - XinFu Zhou
- Neuroregeneration Laboratory Division of Health Sciences School of Pharmacy and Medical Sciences University of South Australia Adelaide South Australia Australia
| | - LiangLong Chen
- Department of Cardiology Fujian Heart Medical Center Fujian Institute of Coronary Heart Disease Fujian Medical University Union Hospital Fuzhou P. R. China
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Yang J, Tan J, Zheng L, Lu CX, Hou WQ, Liu Y, Li QF, Li JX, Cheng D, Luo X, Zhang J. Plasma BDNF and TrkB mRNA in PBMCs Are Correlated With Anti-depressive Effects of 12-Weeks Supervised Exercise During Protracted Methamphetamine Abstinence. Front Mol Neurosci 2020; 13:20. [PMID: 32210759 PMCID: PMC7069447 DOI: 10.3389/fnmol.2020.00020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 01/31/2020] [Indexed: 12/28/2022] Open
Abstract
Purpose: The aim of this study was to evaluate the potential neurotrophic factors and expression of neurotrophin receptors in peripheral blood mononuclear cells linked with the antidepressant action of exercise intervention during protracted methamphetamine (METH) abstinence. Materials and Methods: A total of 72 male METH addicts, including 47 individuals with depression and 25 individuals without depression, were recruited in this study. Individuals with depression were divided into the depression control group and the depression exercised group. Consequently, 12 weeks of supervised exercise intervention was applied. Depression and anxiety were analyzed; plasma brain-derived neurotrophic factor (BDNF), neuronal growth factor (NGF), neurotrophin-3 (NT-3), NT-4, and proBDNF levels were tested using enzyme-linked immunosorbent assay; the mRNA expressions of TrkA, TrkB-FL, TrkB-T1, TrkCB, and P75NTR in peripheral blood mononuclear cells were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Results: NT-4 plasma levels were correlated with depression (r = −0.330, p = 0.005), which remained significant after Bonferroni correction. In addition, the BDNF and NT-3 levels in the plasma were significantly correlated with depression (r = −0.268, p = 0.023; r = −0.259, p = 0.028), but did not reach significance after Bonferroni correction. The BDNF, NT-3, and NT-4 plasma levels were significantly different between the depressive control group and the depressive exercise group using pre-exercise values as the covariate. The fold changes in TrkB-FL and TrkB-T1 mRNA in peripheral blood mononuclear cells between the post-exercise and pre-exercise demonstrated a remarkable decrease (fold change = −11.056 and −39.055). Conclusions: Exercise intervention can alleviate depression and anxiety during protracted METH abstinence. Decrease in BDNF and the expression of TrkB in peripheral blood mononuclear cells occur following the exercise intervention.
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Affiliation(s)
- Jue Yang
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China.,Franklin College of Arts and Sciences, University of Georgia, Athens, GA, United States
| | - Jun Tan
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Lan Zheng
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Chun Xia Lu
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Wen Qi Hou
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Yi Liu
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Qiu Fang Li
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Jin Xiu Li
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Dan Cheng
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Xu Luo
- Hunan Judicial Police Vocational College, Changsha, China
| | - Jun Zhang
- Hunan Judicial Police Vocational College, Changsha, China
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Lohia R, Salari R, Brannigan G. Sequence specificity despite intrinsic disorder: How a disease-associated Val/Met polymorphism rearranges tertiary interactions in a long disordered protein. PLoS Comput Biol 2019; 15:e1007390. [PMID: 31626641 PMCID: PMC6821141 DOI: 10.1371/journal.pcbi.1007390] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 10/30/2019] [Accepted: 09/10/2019] [Indexed: 11/24/2022] Open
Abstract
The role of electrostatic interactions and mutations that change charge states in intrinsically disordered proteins (IDPs) is well-established, but many disease-associated mutations in IDPs are charge-neutral. The Val66Met single nucleotide polymorphism (SNP) in precursor brain-derived neurotrophic factor (BDNF) is one of the earliest SNPs to be associated with neuropsychiatric disorders, and the underlying molecular mechanism is unknown. Here we report on over 250 μs of fully-atomistic, explicit solvent, temperature replica-exchange molecular dynamics (MD) simulations of the 91 residue BDNF prodomain, for both the V66 and M66 sequence. The simulations were able to correctly reproduce the location of both local and non-local secondary structure changes due to the Val66Met mutation, when compared with NMR spectroscopy. We find that the change in local structure is mediated via entropic and sequence specific effects. We developed a hierarchical sequence-based framework for analysis and conceptualization, which first identifies “blobs” of 4-15 residues representing local globular regions or linkers. We use this framework within a novel test for enrichment of higher-order (tertiary) structure in disordered proteins; the size and shape of each blob is extracted from MD simulation of the real protein (RP), and used to parameterize a self-avoiding heterogenous polymer (SAHP). The SAHP version of the BDNF prodomain suggested a protein segmented into three regions, with a central long, highly disordered polyampholyte linker separating two globular regions. This effective segmentation was also observed in full simulations of the RP, but the Val66Met substitution significantly increased interactions across the linker, as well as the number of participating residues. The Val66Met substitution replaces β-bridging between V66 and V94 (on either side of the linker) with specific side-chain interactions between M66 and M95. The protein backbone in the vicinity of M95 is then free to form β-bridges with residues 31-41 near the N-terminus, which condenses the protein. A significant role for Met/Met interactions is consistent with previously-observed non-local effects of the Val66Met SNP, as well as established interactions between the Met66 sequence and a Met-rich receptor that initiates neuronal growth cone retraction. Intrinsically disordered proteins are proteins that have no well-defined structure in at least one functional form. Mutations in one amino acid may still affect their function significantly, especially in subtle ways with cumulative adverse effects on health. Here we report on molecular dynamics simulations of a protein that is critical for neuronal health throughout adulthood (brain-derived neurotrophic factor). We investigate the effects of a mutation carried by 30% of human population, which has been widely studied for its association with aging-related and stress-related disorders, reduced volume of the hippocampus, and variations in episodic memory. We identify a molecular mechanism in which the mutation may change the global conformations of the protein and its ability to bind to receptors.
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Affiliation(s)
- Ruchi Lohia
- Center for Computational and Integrative Biology, Rutgers University, Camden, New Jersey, United States of America
| | - Reza Salari
- Center for Computational and Integrative Biology, Rutgers University, Camden, New Jersey, United States of America
| | - Grace Brannigan
- Center for Computational and Integrative Biology, Rutgers University, Camden, New Jersey, United States of America
- Department of Physics, Rutgers University, Camden, New Jersey, United States of America
- * E-mail:
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Bothwell M. Recent advances in understanding context-dependent mechanisms controlling neurotrophin signaling and function. F1000Res 2019; 8:F1000 Faculty Rev-1658. [PMID: 31583078 PMCID: PMC6758832 DOI: 10.12688/f1000research.19174.1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/11/2019] [Indexed: 01/01/2023] Open
Abstract
Complex mechanisms control the signaling of neurotrophins through p75 NTR and Trk receptors, allowing cellular responses that are highly context dependent, particularly in the nervous system and particularly with regard to the neurotrophin brain-derived neurotrophic factor (BDNF). Recent reports describe a variety of sophisticated regulatory mechanisms that contribute to such functional flexibility. Mechanisms described include regulation of trafficking of alternative BDNF transcripts, regulation of post-translational processing and secretion of BDNF, engagement of co-receptors that influence localization and signaling of p75 NTR and Trk receptors, and control of trafficking of receptors in the endocytic pathway and during anterograde and retrograde axonal transport.
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Affiliation(s)
- Mark Bothwell
- Department of Physiology & Biophysics, University of Washington Medical Center, Seattle, WA, 98195-7290, USA
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19
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Investigating the Conformational Response of the Sortilin Receptor upon Binding Endogenous Peptide- and Protein Ligands by HDX-MS. Structure 2019; 27:1103-1113.e3. [PMID: 31104815 DOI: 10.1016/j.str.2019.04.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 02/28/2019] [Accepted: 04/10/2019] [Indexed: 11/20/2022]
Abstract
Sortilin is a multifunctional neuronal receptor involved in sorting of neurotrophic factors and apoptosis signaling. So far, structural characterization of sortilin and its endogenous ligands has been limited to crystallographic studies of sortilin in complex with the neuropeptide neurotensin. Here, we use hydrogen/deuterium exchange mass spectrometry to investigate the conformational response of sortilin to binding biological ligands including the peptides neurotensin and the sortilin propeptide and the proteins progranulin and pro-nerve growth factor-β. The results show that the ligands use two binding sites inside the cavity of the β-propeller of sortilin. However, ligands have distinct differences in their conformational impact on the receptor. Interestingly, the protein ligands induce conformational stabilization in a remote membrane-proximal domain, hinting at an unknown conformational link between the ligand binding region and this membrane-proximal region of sortilin. Our findings improve our structural understanding of sortilin and how it mediates diverse ligand-dependent functions important in neurobiology.
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20
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Xu J, Song J, Yang X, Guo J, Wang T, Zhuo W. ProNGF siRNA inhibits cell proliferation and invasion of pancreatic cancer cells and promotes anoikis. Biomed Pharmacother 2019; 111:1066-1073. [PMID: 30841420 DOI: 10.1016/j.biopha.2019.01.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 12/21/2018] [Accepted: 01/01/2019] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND Precursor of nerve growth factor (proNGF) was previously considered biologically inactive; however, it has recently been identified as having important roles in the pathology of cancer development. AIM This study aimed to explore the therapeutic effects of proNGF siRNA on the proliferation, invasion, and anoikis of pancreatic cancer cells and determine the functions of proNGF. METHODS Pancreatic ductal adenocarcinoma (PDAC) and paired paracancerous tissue samples were collected from 60 patients for evaluation of proNGF expression by immunohistochemistry staining, qPCR, and western blotting. PDAC cell proliferation, migration, apoptosis, and anoikis following proNGF siRNA knockdown were investigated in two pancreatic cancer cell lines, Panc-1 and Bxpc-3, using BrdU incorporation assays, EdU staining, Ki-67 immunofluorescence (IF) staining, wound-healing assays, transwell invasion assays, and EthD-1 IF staining. Autophagy-related proteins were also measured by western blotting. RESULTS Levels of proNGF protein were higher in pancreatic cancer tissues and cells lines than those in paracancerous tissues and normal pancreatic duct epithelial cells, respectively. In vitro, ProNGF knockdown by siRNA led to significantly reduced cell proliferation, remarkably inhibited wound-healing, and reduced the number of invaded PDAC cells in migration and transwell assays. Treatment with proNGF siRNA also downregulated ATG5 and Beclin 1 protein levels, increased those of P62, and increased EthD-1 staining in PDAC cells. CONCLUSION ProNGF expression is elevated in PDAC tissues and cell lines, and proNGF siRNA can inhibit cell proliferation, migration, and invasion, and promote anoikis of pancreatic cancer cells, in which decreased proNGF may participate.
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Affiliation(s)
- Jianbiao Xu
- Second Department of General Surgery, The First People's Hospital of Yunnan Province, Kunming 650032, China; The Affiliated Hospital of Kunming University of Science and Technology, Kunming 650032, China
| | - Jianlin Song
- Second Department of General Surgery, The First People's Hospital of Yunnan Province, Kunming 650032, China; The Affiliated Hospital of Kunming University of Science and Technology, Kunming 650032, China
| | - Xiaochun Yang
- The Affiliated Hospital of Kunming University of Science and Technology, Kunming 650032, China; Department of Ophthalmology, The First People's Hospital of Yunnan Province, Kunming 650032, China.
| | - Jianhui Guo
- Second Department of General Surgery, The First People's Hospital of Yunnan Province, Kunming 650032, China; The Affiliated Hospital of Kunming University of Science and Technology, Kunming 650032, China.
| | - Tongmin Wang
- Second Department of General Surgery, The First People's Hospital of Yunnan Province, Kunming 650032, China; The Affiliated Hospital of Kunming University of Science and Technology, Kunming 650032, China
| | - Weidong Zhuo
- Second Department of General Surgery, The First People's Hospital of Yunnan Province, Kunming 650032, China; The Affiliated Hospital of Kunming University of Science and Technology, Kunming 650032, China
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ProNGF increases breast tumor aggressiveness through functional association of TrkA with EphA2. Cancer Lett 2019; 449:196-206. [PMID: 30771434 DOI: 10.1016/j.canlet.2019.02.019] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 02/07/2019] [Accepted: 02/10/2019] [Indexed: 12/19/2022]
Abstract
ProNGF expression has been linked to several types of cancers including breast cancer, and we have previously shown that proNGF stimulates breast cancer invasion in an autocrine manner through membrane receptors sortilin and TrkA. However, little is known regarding TrkA-associated protein partners upon proNGF stimulation. By proteomic analysis and proximity ligation assays, we found that proNGF binding to sortilin induced sequential formation of the functional sortilin/TrkA/EphA2 complex, leading to TrkA-phosphorylation dependent Akt activation and EphA2-dependent Src activation. EphA2 inhibition using siRNA approach abolished proNGF-stimulated clonogenic growth of breast cancer cell lines. Combinatorial targeting of TrkA and EphA2 dramatically reduced colony formation in vitro, primary tumor growth and metastatic dissemination towards the brain in vivo. Finally, proximity ligation assay in breast tumor samples revealed that increased TrkA/EphA2 proximity ligation assay signals were correlated with a decrease of overall survival in patients. All together, these data point out the importance of TrkA/EphA2 functional association in proNGF-induced tumor promoting effects, and provide a rationale to target proNGF/TrkA/EphA2 axis by alternative methods other than the simple use of tyrosine kinase inhibitors in breast cancer.
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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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Liu S, Guo W, Zhou H, Tang L, Feng S, Zhong JH, Zhou XF. proBDNF inhibits the proliferation and migration of OLN‑93 oligodendrocytes. Mol Med Rep 2018; 18:3809-3817. [PMID: 30132570 PMCID: PMC6131500 DOI: 10.3892/mmr.2018.9407] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 05/03/2018] [Indexed: 01/11/2023] Open
Abstract
In contrast with mature brain-derived neurotrophic factor (mBDNF), proBDNF induces cell apoptosis. However, the function of proBDNF in oligodendrocytes remains unclear. In the present study, the OLN-93 oligodendroglia cell line was utilized as an in vitro model to analyse the functions of proBDNF in oligodendroglia. p75NTR, sortilin and proBDNF were expressed in cultured OLN-93 cells. It was indicated that proBDNF inhibited OLN-93 cell proliferation in a dose-dependent manner as determined using the MTT assay and BrdU staining. Furthermore, proBDNF suppressed the migration of OLN-93 cells as demonstrated using the scratch assay. proBDNF also decreased cell viability and promoted apoptosis as indicated by activated cysteine-aspartic acid protease-3 (caspase-3) immunocytochemistry. Notably, anti-proBDNF treatment neutralized the effect of proBDNF and resulted in increased cell proliferation and migration and decreased apoptosis. However, these effects were not observed in the presence of recombinant p75NTR extracellular domain-human FC fusion protein and p75NTR antibody, indicating that proBDNF imparts its inhibitory effects on oligodendrocytes through the p75NTR signal pathway.
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Affiliation(s)
- Shen Liu
- School of Pharmacy and Medical Science and Sansom Institute, Division of Health Sciences, University of South Australia, Adelaide SA5000, Australia
| | - Wei Guo
- Orthopaedic Department of Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Hengxing Zhou
- Orthopaedic Department of Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Liang Tang
- Orthopaedic Department of Tianjin Haihe Hospital, Tianjin 300000, P.R. China
| | - Shiqing Feng
- Orthopaedic Department of Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Jin-Hua Zhong
- School of Pharmacy and Medical Science and Sansom Institute, Division of Health Sciences, University of South Australia, Adelaide SA5000, Australia
| | - Xin-Fu Zhou
- School of Pharmacy and Medical Science and Sansom Institute, Division of Health Sciences, University of South Australia, Adelaide SA5000, Australia
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The ProNGF/p75NTR pathway induces tau pathology and is a therapeutic target for FTLD-tau. Mol Psychiatry 2018; 23:1813-1824. [PMID: 29867188 DOI: 10.1038/s41380-018-0071-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Revised: 01/26/2018] [Accepted: 03/26/2018] [Indexed: 11/09/2022]
Abstract
Tau pathology is characterized as a form of frontotemporal lobar degeneration (FTLD) known as FTLD-tau. The underlying pathogenic mechanisms are not known and no therapeutic interventions are currently available. Here, we report that the neurotrophin receptor p75NTR plays a critical role in the pathogenesis of FTLD-tau. The expression of p75NTR and the precursor of nerve growth factor (proNGF) were increased in the brains of FTLD-tau patients and mice (P301L transgenic). ProNGF-induced tau phosphorylation via p75NTR in vitro, which was associated with the AKT/glycogen synthase kinase (GSK)3β pathway. Genetic reduction of p75NTR in P301L mice rescued the memory deficits, alleviated tau hyperphosphorylation and restored the activity of the AKT/GSK3β pathway. Treatment of the P301L mice with the soluble p75NTR extracellular domain (p75ECD-Fc), which can antagonize neurotoxic ligands of p75NTR, effectively improved memory behavior and suppressed tau pathology. This suggests that p75NTR plays a crucial role in tau paGSKthology and represents a potential druggable target for FTLD-tau and related tauopathies.
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25
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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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26
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Kennedy AE, Laamanen CA, Ross MS, Vohra R, Boreham DR, Scott JA, Ross GM. Nerve growth factor inhibitor with novel-binding domain demonstrates nanomolar efficacy in both cell-based and cell-free assay systems. Pharmacol Res Perspect 2018; 5. [PMID: 28971611 PMCID: PMC5625151 DOI: 10.1002/prp2.339] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 03/30/2017] [Accepted: 04/20/2017] [Indexed: 12/15/2022] Open
Abstract
Nerve growth factor (NGF), a member of the neurotrophin family, is known to regulate the development and survival of a select population of neurons through the binding and activation of the TrkA receptor. Elevated levels of NGF have been associated with painful pathologies such as diabetic neuropathy and fibromyalgia. However, completely inhibiting the NGF signal could hold significant side effects, such as those observed in a genetic condition called congenital insensitivity to pain and anhidrosis (CIPA). Previous methods of screening for NGF‐inhibitors used labeling techniques which have the potential to alter molecular interactions. SPR spectroscopy and NGF‐dependent cellular assays were utilized to identify a novel NGF‐inhibitor, BVNP‐0197 (IC50 = 90 nmol/L), the first NGF‐inhibitor described with a high nanomolar NGF inhibition efficiency. The present study utilizes molecular modeling flexible docking to identify a novel binding domain in the loop II/IV cleft of NGF.
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Affiliation(s)
- Allison E Kennedy
- Northern Ontario School of Medicine, Sudbury, Ontario, Canada.,Laurentian University, Biomolecular Sciences Program, Sudbury, Ontario, Canada
| | - Corey A Laamanen
- Northern Ontario School of Medicine, Sudbury, Ontario, Canada.,Laurentian University, Bharti School of Engineering, Sudbury, Ontario, Canada
| | - Mitchell S Ross
- Northern Ontario School of Medicine, Sudbury, Ontario, Canada
| | - Rahul Vohra
- Northern Ontario School of Medicine, Sudbury, Ontario, Canada.,Sussex Research Laboratories Inc., Ottawa, Ontario, Canada
| | | | - John A Scott
- Northern Ontario School of Medicine, Sudbury, Ontario, Canada.,Laurentian University, Bharti School of Engineering, Sudbury, Ontario, Canada
| | - Gregory M Ross
- Northern Ontario School of Medicine, Sudbury, Ontario, Canada
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27
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Medina-Cucurella AV, Zhu Y, Bowen SJ, Bergeron LM, Whitehead TA. Pro region engineering of nerve growth factor by deep mutational scanning enables a yeast platform for conformational epitope mapping of anti-NGF monoclonal antibodies. Biotechnol Bioeng 2018; 115:1925-1937. [PMID: 29663315 DOI: 10.1002/bit.26706] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 03/29/2018] [Accepted: 04/03/2018] [Indexed: 01/19/2023]
Abstract
Nerve growth factor (NGF) plays a central role in multiple chronic pain conditions. As such, anti-NGF monoclonal antibodies (mAbs) that function by antagonizing NGF downstream signaling are leading drug candidates for non-opioid pain relief. To evaluate anti-canine NGF (cNGF) mAbs we sought a yeast surface display platform of cNGF. Both mature cNGF and pro-cNGF displayed on the yeast surface but bound conformationally sensitive mAbs at most 2.5-fold in mean fluorescence intensity above background, suggesting that cNGF was mostly misfolded. To improve the amount of folded, displayed cNGF, we used comprehensive mutagenesis, FACS, and deep sequencing to identify point mutants in the pro-region of canine NGF that properly enhance the folded protein displayed on the yeast surface. Out of 1,737 tested single point mutants in the pro region, 49 increased the amount of NGF recognized by conformationally sensitive mAbs. These gain-of-function mutations cluster around residues A-61-P-26. Gain-of-function mutants were additive, and a construct containing three mutations increased amount of folded cNGF to 23-fold above background. Using this new cNGF construct, fine conformational epitopes for tanezumab and three anti-cNGF mAbs were evaluated. The epitope revealed by the yeast experiments largely overlapped with the tanezumab epitope previously determined by X-ray crystallography. The other mAbs showed site-specific differences with tanezumab. As the number of binding epitopes of functionally neutralizing anti-NGF mAbs on NGF are limited, subtle differences in the individual interacting residues on NGF that bind each mAb contribute to the understanding of each antibody and variations in its neutralizing activity. These results demonstrate the potential of deep sequencing-guided protein engineering to improve the production of folded surface-displayed protein, and the resulting cNGF construct provides a platform to map conformational epitopes for other anti-neurotrophin mAbs.
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Affiliation(s)
- Angélica V Medina-Cucurella
- Department of Chemical Engineering and Materials Science, Michigan State University Engineering Building, East Lansing, Michigan
| | - Yaqi Zhu
- Zoetis Global Therapeutic Research, Veterinary Medicine Research and Development, Kalamazoo, Michigan
| | - Scott J Bowen
- Zoetis Global Therapeutic Research, Veterinary Medicine Research and Development, Kalamazoo, Michigan
| | - Lisa M Bergeron
- Zoetis Global Therapeutic Research, Veterinary Medicine Research and Development, Kalamazoo, Michigan
| | - Timothy A Whitehead
- Department of Chemical Engineering and Materials Science, Michigan State University Engineering Building, East Lansing, Michigan.,Department of Biosystems and Agricultural Engineering, Michigan State University, East Lansing, Michigan.,Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, Michigan
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28
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Xu SY, Jiang J, Pan A, Yan C, Yan XX. Sortilin: a new player in dementia and Alzheimer-type neuropathology. Biochem Cell Biol 2018; 96:491-497. [PMID: 29687731 DOI: 10.1139/bcb-2018-0023] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Age-related dementias are now a major mortality factor among most human populations in the world, with Alzheimer's disease (AD) being the leading dementia-causing neurodegenerative disease. The pathogenic mechanism underlying dementia disorders, and AD in particular, remained largely unknown. Efforts to develop drugs targeting the disease's hallmark lesions, such as amyloid plaque and tangle pathologies, have been unsuccessful so far. The vacuolar protein sorting 10p (Vps10p) family plays a critical role in membrane signal transduction and protein sorting and trafficking between intracellular compartments. Data emerging during the past few years point to an involvement of this family in the development of AD. Specifically, the Vps10p member sortilin has been shown to participate in amyloid plaque formation, tau phosphorylation, abnormal protein sorting and apoptosis. In this minireview, we update some latest findings from animal experiments and human brain studies suggesting that abnormal sortilin expression is associated with AD-type neuropathology, warranting further research that might lead to novel targets for the development of AD therapies.
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Affiliation(s)
- Shu-Yin Xu
- a Department of Anatomy and Neurobiology, Xiangya School of Medicine, Central South University, Changsha, Hunan 410013, China
| | - Juan Jiang
- a Department of Anatomy and Neurobiology, Xiangya School of Medicine, Central South University, Changsha, Hunan 410013, China
| | - Aihua Pan
- a Department of Anatomy and Neurobiology, Xiangya School of Medicine, Central South University, Changsha, Hunan 410013, China
| | - Cai Yan
- a Department of Anatomy and Neurobiology, Xiangya School of Medicine, Central South University, Changsha, Hunan 410013, China.,b Department of Histology and Embryology, Xiangya School of Medicine, Central South University, Changsha, Hunan 410013, China
| | - Xiao-Xin Yan
- a Department of Anatomy and Neurobiology, Xiangya School of Medicine, Central South University, Changsha, Hunan 410013, China
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29
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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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30
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Greenwood SG, Montroull L, Volosin M, Scharfman HE, Teng KK, Light M, Torkin R, Maxfield F, Hempstead BL, Friedman WJ. A Novel Neuroprotective Mechanism for Lithium That Prevents Association of the p75 NTR-Sortilin Receptor Complex and Attenuates proNGF-Induced Neuronal Death In Vitro and In Vivo. eNeuro 2018; 5:ENEURO.0257-17.2017. [PMID: 29349290 PMCID: PMC5771681 DOI: 10.1523/eneuro.0257-17.2017] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 11/17/2017] [Accepted: 11/21/2017] [Indexed: 12/12/2022] Open
Abstract
Neurotrophins play critical roles in the survival, maintenance and death of neurons. In particular, proneurotrophins have been shown to mediate cell death following brain injury induced by status epilepticus (SE) in rats. Previous studies have shown that pilocarpine-induced seizures lead to increased levels of proNGF, which binds to the p75NTR-sortilin receptor complex to elicit apoptosis. A screen to identify compounds that block proNGF binding and uptake into cells expressing p75 and sortilin identified lithium citrate as a potential inhibitor of proNGF and p75NTR-mediated cell death. In this study, we demonstrate that low, submicromolar doses of lithium citrate effectively inhibited proNGF-induced cell death in cultured neurons and protected hippocampal neurons following pilocarpine-induced SE in vivo. We analyzed specific mechanisms by which lithium citrate afforded neuroprotection and determined that lithium citrate prevented the association and internalization of the p75NTR-sortilin receptor complex. Our results demonstrate a novel mechanism by which low-dose treatments of lithium citrate are effective in attenuating p75NTR-mediated cell death in vitro and in vivo.
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Affiliation(s)
| | - Laura Montroull
- Department of Biological Science, Rutgers University, Newark, NJ 07102
| | - Marta Volosin
- Department of Biological Science, Rutgers University, Newark, NJ 07102
| | | | - Kenneth K. Teng
- Department of Medicine, Weill Cornell Medical College, New York, NY
| | - Matthew Light
- Department of Medicine, Weill Cornell Medical College, New York, NY
| | - Risa Torkin
- Department of Medicine, Weill Cornell Medical College, New York, NY
| | | | | | - Wilma J. Friedman
- Department of Biological Science, Rutgers University, Newark, NJ 07102
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31
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Januliene D, Andersen JL, Nielsen JA, Quistgaard EM, Hansen M, Strandbygaard D, Moeller A, Petersen CM, Madsen P, Thirup SS. Acidic Environment Induces Dimerization and Ligand Binding Site Collapse in the Vps10p Domain of Sortilin. Structure 2017; 25:1809-1819.e3. [DOI: 10.1016/j.str.2017.09.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 08/21/2017] [Accepted: 09/25/2017] [Indexed: 12/30/2022]
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32
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Leloup N, Lössl P, Meijer DH, Brennich M, Heck AJR, Thies-Weesie DME, Janssen BJC. Low pH-induced conformational change and dimerization of sortilin triggers endocytosed ligand release. Nat Commun 2017; 8:1708. [PMID: 29167428 PMCID: PMC5700061 DOI: 10.1038/s41467-017-01485-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 09/19/2017] [Indexed: 11/24/2022] Open
Abstract
Low pH-induced ligand release and receptor recycling are important steps for endocytosis. The transmembrane protein sortilin, a β-propeller containing endocytosis receptor, internalizes a diverse set of ligands with roles in cell differentiation and homeostasis. The molecular mechanisms of pH-mediated ligand release and sortilin recycling are unresolved. Here we present crystal structures that show the sortilin luminal segment (s-sortilin) undergoes a conformational change and dimerizes at low pH. The conformational change, within all three sortilin luminal domains, provides an altered surface and the dimers sterically shield a large interface while bringing the two s-sortilin C-termini into close proximity. Biophysical and cell-based assays show that members of two different ligand families, (pro)neurotrophins and neurotensin, preferentially bind the sortilin monomer. This indicates that sortilin dimerization and conformational change discharges ligands and triggers recycling. More generally, this work may reveal a double mechanism for low pH-induced ligand release by endocytosis receptors. Sortilin is an endocytosis receptor with a luminal β-propeller domain. Here the authors present the structures of the β-propeller domain at neutral and acidic pH, which reveal that sortilin dimerises and undergoes conformational changes at low pH and further propose a model for low pH-induced ligand release by endocytosis receptors.
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Affiliation(s)
- Nadia Leloup
- Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Faculty of Science, Utrecht University, 3584 CH, Utrecht, The Netherlands
| | - Philip Lössl
- Biomolecular Mass Spectrometry & Proteomics and Netherlands Proteomics Center, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, 3584 CH, Utrecht, The Netherlands
| | - Dimphna H Meijer
- Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Faculty of Science, Utrecht University, 3584 CH, Utrecht, The Netherlands
| | - Martha Brennich
- European Molecular Biology Laboratory, Grenoble Outstation, Grenoble, 38000, France
| | - Albert J R Heck
- Biomolecular Mass Spectrometry & Proteomics and Netherlands Proteomics Center, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, 3584 CH, Utrecht, The Netherlands
| | - Dominique M E Thies-Weesie
- Van't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University, 3584 CH, Utrecht, The Netherlands
| | - Bert J C Janssen
- Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Faculty of Science, Utrecht University, 3584 CH, Utrecht, The Netherlands.
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33
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Schwarz E. Cystine knot growth factors and their functionally versatile proregions. Biol Chem 2017; 398:1295-1308. [PMID: 28771427 DOI: 10.1515/hsz-2017-0163] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 07/16/2017] [Indexed: 12/23/2022]
Abstract
The cystine knot disulfide pattern has been found to be widespread in nature, since it has been detected in proteins from plants, marine snails, spiders and mammals. Cystine knot proteins are secreted proteins. Their functions range from defense mechanisms as toxins, e.g. ion channel or enzyme inhibitors, to hormones, blood factors and growth factors. Cystine knot proteins can be divided into two superordinate groups. (i) The cystine knot peptides, also referred to - with other non-cystine knot proteins - as knottins, with linear and cyclic polypeptide chains. (ii) The cystine knot growth factor family, which is in the focus of this article. The disulfide ring structure of the cystine knot peptides is made up by the half-cystines 1-4 and 2-5, and the threading disulfide bond is formed by the half-cystines, 3-6. In the growth factor group, the disulfides of half-cystines 1 and 4 pass the ring structure formed by the half-cystines 2-5 and 3-6. In this review, special emphasis will be devoted to the growth factor cystine knot proteins and their proregions. The latter have shifted into the focus of scientific interest as their important biological roles are just to be unravelled.
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34
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Carleton LA, Chakravarthy R, van der Sloot AM, Mnich K, Serrano L, Samali A, Gorman AM. Generation of rationally-designed nerve growth factor (NGF) variants with receptor specificity. Biochem Biophys Res Commun 2017; 495:700-705. [PMID: 29108999 DOI: 10.1016/j.bbrc.2017.11.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 11/01/2017] [Indexed: 10/18/2022]
Abstract
Nerve growth factor (NGF) is the prototypic member of the neurotrophin family and binds two receptors, TrkA and the 75 kDa neurotrophin receptor (p75NTR), through which diverse and sometimes opposing effects are mediated. Using the FoldX protein design algorithm, we generated eight NGF variants with different point mutations predicted to have altered binding to TrkA or p75NTR. Of these, the I31R NGF variant exhibited specific binding to p75NTR. The generation of this NGF variant with selective affinity for p75NTR can be used to enhance understanding of neurotrophin receptor imbalance in diseases and identifies a key targetable residue for the development of small molecules to disrupt binding of NGF to TrkA with potential uses in chronic pain.
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Affiliation(s)
| | | | - Almer M van der Sloot
- EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation, Barcelona, Spain; Institute for Research in Immunology and Cancer, University of Montréal, Montreal, QC, Canada
| | | | - Luis Serrano
- EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation, Barcelona, Spain; Universitat Pompeu Fabra, 08003 Barcelona, Spain; Institució Catalana de Recerca i Estudis Avançats, Pg. Lluís Companys 23, 08010 Barcelona, Spain
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35
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Trabjerg E, Kartberg F, Christensen S, Rand KD. Conformational characterization of nerve growth factor-β reveals that its regulatory pro-part domain stabilizes three loop regions in its mature part. J Biol Chem 2017; 292:16665-16676. [PMID: 28798232 DOI: 10.1074/jbc.m117.803320] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 08/07/2017] [Indexed: 11/06/2022] Open
Abstract
Nerve growth factor-β (NGF) is essential for the correct development of the nervous system. NGF exists in both a mature form and a pro-form (proNGF). The two forms have opposing effects on neurons: NGF induces proliferation, whereas proNGF induces apoptosis via binding to a receptor complex of the common neurotrophin receptor (p75NTR) and sortilin. The overexpression of both proNGF and sortilin has been associated with several neurodegenerative diseases. Insights into the conformational differences between proNGF and NGF are central to a better understanding of the opposing mechanisms of action of NGF and proNGF on neurons. However, whereas the structure of NGF has been determined by X-ray crystallography, the structural details for proNGF remain elusive. Here, using a sensitive MS-based analytical method to measure the hydrogen/deuterium exchange of proteins in solution, we analyzed the conformational properties of proNGF and NGF. We detected the presence of a localized higher-order structure motif in the pro-part of proNGF. Furthermore, by comparing the hydrogen/deuterium exchange in the mature part of NGF and proNGF, we found that the presence of the pro-part in proNGF causes a structural stabilization of three loop regions in the mature part, possibly through a direct molecular interaction. Moreover, using tandem MS analyses, we identified two N-linked and two O-linked glycosylations in the pro-part of proNGF. These results advance our knowledge of the conformational properties of proNGF and NGF and help provide a rationale for the diverse biological effects of NGF and proNGF at the molecular level.
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Affiliation(s)
- Esben Trabjerg
- From the Department of Pharmacy, University of Copenhagen, 2100 Copenhagen E, Denmark and.,the Department of Biologics, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark
| | - Fredrik Kartberg
- the Department of Biologics, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark
| | - Søren Christensen
- the Department of Biologics, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark
| | - Kasper D Rand
- From the Department of Pharmacy, University of Copenhagen, 2100 Copenhagen E, Denmark and
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36
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Zhang J, Liu R, Kuang HY, Gao XY, Liu HL. Protective treatments and their target retinal ganglion cells in diabetic retinopathy. Brain Res Bull 2017; 132:53-60. [DOI: 10.1016/j.brainresbull.2017.05.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Accepted: 05/10/2017] [Indexed: 12/19/2022]
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37
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Haddad Y, Adam V, Heger Z. Trk Receptors and Neurotrophin Cross-Interactions: New Perspectives Toward Manipulating Therapeutic Side-Effects. Front Mol Neurosci 2017; 10:130. [PMID: 28515680 PMCID: PMC5414483 DOI: 10.3389/fnmol.2017.00130] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 04/18/2017] [Indexed: 12/02/2022] Open
Abstract
Some therapeutic side-effects result from simultaneous activation of homolog receptors by the same ligand. Tropomyosin receptor kinases (TrkA, TrkB and TrkC) play a major role in the development and biology of neurons through neurotrophin signaling. The wide range of cross-interactions between Trk receptors and neurotrophins vary in selectivity, affinity and function. In this study, we discuss new perspectives to the manipulation of side-effects via a better understanding of the cross-interactions at the molecular level, derived by computational methods. Available crystal structures of Trk receptors and neurotrophins are a valuable resource for exploitation via molecular mechanics (MM) and dynamics (MD). The study of the energetics and dynamics of neurotrophins or neurotrophic peptides interacting with Trk receptors will provide insight to structural regions that may be candidates for drug targeting and signaling pathway selection.
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Affiliation(s)
- Yazan Haddad
- Department of Chemistry and Biochemistry, Mendel University in BrnoBrno, Czechia.,Central European Institute of Technology, Brno University of TechnologyBrno, Czechia
| | - Vojtěch Adam
- Department of Chemistry and Biochemistry, Mendel University in BrnoBrno, Czechia.,Central European Institute of Technology, Brno University of TechnologyBrno, Czechia
| | - Zbyněk Heger
- Department of Chemistry and Biochemistry, Mendel University in BrnoBrno, Czechia.,Central European Institute of Technology, Brno University of TechnologyBrno, Czechia
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38
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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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39
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Zanin JP, Unsain N, Anastasia A. Growth factors and hormones pro-peptides: the unexpected adventures of the BDNF prodomain. J Neurochem 2017; 141:330-340. [PMID: 28218971 DOI: 10.1111/jnc.13993] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 02/08/2017] [Accepted: 02/13/2017] [Indexed: 12/26/2022]
Abstract
Most growth factors and hormones are synthesized as pre-pro-proteins which are processed to the biologically active mature protein. The pre- and prodomains are cleaved from the precursor protein in the secretory pathway or, in some cases, extracellularly. The canonical functions of these prodomains are to assist in folding and stabilization of the mature domain, to direct intra and extracellular localization, to facilitate storage, and to regulate bioavailability of their mature counterpart. Recently, exciting evidence has revealed that prodomains of certain growth factors, after cleaved from the precursor pro-protein, can act as independent active signaling molecules. In this review, we discuss the various classical functions of prodomains, and the biological consequences of these pro-peptides acting as ligands. We will focus our attention on the brain-derived neurotrophic factor prodomain (pBDNF), which has been recently described as a novel secreted ligand influencing neuronal morphology and physiology.
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Affiliation(s)
- Juan Pablo Zanin
- Department of Biological Sciences, Rutgers University, Newark, New Jersey, USA
| | - Nicolás Unsain
- Instituto de Investigación Médica Mercedes y Martin Ferreyra, (INIMEC-CONICET-Universidad Nacional de Córdoba), Córdoba, Argentina
| | - Agustin Anastasia
- Instituto de Investigación Médica Mercedes y Martin Ferreyra, (INIMEC-CONICET-Universidad Nacional de Córdoba), Córdoba, Argentina
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Cobianchi S, Arbat-Plana A, López-Álvarez VM, Navarro X. Neuroprotective Effects of Exercise Treatments After Injury: The Dual Role of Neurotrophic Factors. Curr Neuropharmacol 2017; 15:495-518. [PMID: 27026050 PMCID: PMC5543672 DOI: 10.2174/1570159x14666160330105132] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 02/19/2016] [Accepted: 03/03/2016] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Shared connections between physical activity and neuroprotection have been studied for decades, but the mechanisms underlying this effect of specific exercise were only recently brought to light. Several evidences suggest that physical activity may be a reasonable and beneficial method to improve functional recovery in both peripheral and central nerve injuries and to delay functional decay in neurodegenerative diseases. In addition to improving cardiac and immune functions, physical activity may represent a multifunctional approach not only to improve cardiocirculatory and immune functions, but potentially modulating trophic factors signaling and, in turn, neuronal function and structure at times that may be critical for neurodegeneration and regeneration. METHODS Research content related to the effects of physical activity and specific exercise programs in normal and injured nervous system have been reviewed. RESULTS Sustained exercise, particularly if applied at moderate intensity and early after injury, exerts anti-inflammatory and pro-regenerative effects, and may boost cognitive and motor functions in aging and neurological disorders. However, newest studies show that exercise modalities can differently affect the production and function of brain-derived neurotrophic factor and other neurotrophins involved in the generation of neuropathic conditions. These findings suggest the possibility that new exercise strategies can be directed to nerve injuries with therapeutical benefits. CONCLUSION Considering the growing burden of illness worldwide, understanding of how modulation of neurotrophic factors contributes to exercise-induced neuroprotection and regeneration after peripheral nerve and spinal cord injuries is a relevant topic for research, and represents the beginning of a new non-pharmacological therapeutic approach for better rehabilitation of neural disorders.
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Affiliation(s)
- Stefano Cobianchi
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, Universitat Autonoma de Barcelona, Bellaterra, Spain
- Centro de Investigacion Biomedica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain
| | - Ariadna Arbat-Plana
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, Universitat Autonoma de Barcelona, Bellaterra, Spain
- Centro de Investigacion Biomedica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain
| | - Víctor M. López-Álvarez
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, Universitat Autonoma de Barcelona, Bellaterra, Spain
- Centro de Investigacion Biomedica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain
| | - Xavier Navarro
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, Universitat Autonoma de Barcelona, Bellaterra, Spain
- Centro de Investigacion Biomedica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain
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Paoletti F, de Chiara C, Kelly G, Covaceuszach S, Malerba F, Yan R, Lamba D, Cattaneo A, Pastore A. Conformational Rigidity within Plasticity Promotes Differential Target Recognition of Nerve Growth Factor. Front Mol Biosci 2016; 3:83. [PMID: 28083536 PMCID: PMC5183593 DOI: 10.3389/fmolb.2016.00083] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Accepted: 12/02/2016] [Indexed: 12/23/2022] Open
Abstract
Nerve Growth Factor (NGF), the prototype of the neurotrophin family, is essential for maintenance and growth of different neuronal populations. The X-ray crystal structure of NGF has been known since the early '90s and shows a β-sandwich fold with extensive loops that are involved in the interaction with its binding partners. Understanding the dynamical properties of these loops is thus important for molecular recognition. We present here a combined solution NMR/molecular dynamics study which addresses the question of whether and how much the long loops of NGF are flexible and describes the N-terminal intrinsic conformational tendency of the unbound NGF molecule. NMR titration experiments allowed identification of a previously undetected epitope of the anti-NGF antagonist antibody αD11 which will be of crucial importance for future drug lead discovery. The present study thus recapitulates all the available structural information and unveils the conformational versatility of the relatively rigid NGF loops upon functional ligand binding.
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Affiliation(s)
- Francesca Paoletti
- Neurotrophic Factors and Neurodegenerative Diseases Unit, European Brain Research, Rita Levi-Montalcini FoundationRome, Italy; Scuola Normale SuperiorePisa, Italy
| | | | - Geoff Kelly
- Medical Research Council (MRC) Biomedical NMR Centre, The Francis Crick Institute London, UK
| | - Sonia Covaceuszach
- Istituto di Cristallografia, Consiglio Nazionale delle Ricerche (CNR), Sede Secondaria di Basovizza Trieste, Italy
| | - Francesca Malerba
- Neurotrophic Factors and Neurodegenerative Diseases Unit, European Brain Research, Rita Levi-Montalcini FoundationRome, Italy; Scuola Normale SuperiorePisa, Italy
| | - Robert Yan
- Maurice Wohl Institute, Department of Basic and Clinical Neuroscience, King's College London London, UK
| | - Doriano Lamba
- Istituto di Cristallografia, Consiglio Nazionale delle Ricerche (CNR), Sede Secondaria di Basovizza Trieste, Italy
| | - Antonino Cattaneo
- Neurotrophic Factors and Neurodegenerative Diseases Unit, European Brain Research, Rita Levi-Montalcini FoundationRome, Italy; Scuola Normale SuperiorePisa, Italy
| | - Annalisa Pastore
- Maurice Wohl Institute, Department of Basic and Clinical Neuroscience, King's College LondonLondon, UK; Molecular Medicine Department, University of PaviaPavia, Italy
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Pediaditakis I, Kourgiantaki A, Prousis KC, Potamitis C, Xanthopoulos KP, Zervou M, Calogeropoulou T, Charalampopoulos I, Gravanis A. BNN27, a 17-Spiroepoxy Steroid Derivative, Interacts With and Activates p75 Neurotrophin Receptor, Rescuing Cerebellar Granule Neurons from Apoptosis. Front Pharmacol 2016; 7:512. [PMID: 28082899 PMCID: PMC5183592 DOI: 10.3389/fphar.2016.00512] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 12/12/2016] [Indexed: 12/02/2022] Open
Abstract
Neurotrophin receptors mediate a plethora of signals affecting neuronal survival. The p75 pan-neurotrophin receptor controls neuronal cell fate after its selective activation by immature and mature isoforms of all neurotrophins. It also exerts pleiotropic effects interacting with a variety of ligands in different neuronal or non-neuronal cells. In the present study, we explored the biophysical and functional interactions of a blood-brain-barrier (BBB) permeable, C17-spiroepoxy steroid derivative, BNN27, with p75NTR receptor. BNN27 was recently shown to bind to NGF high-affinity receptor, TrkA. We now tested the p75NTR-mediated effects of BNN27 in mouse Cerebellar Granule Neurons (CGNs), expressing p75NTR, but not TrkA receptors. Our findings show that BNN27 physically interacts with p75NTR receptors in specific amino-residues of its extracellular domain, inducing the recruitment of p75NTR receptor to its effector protein RIP2 and the simultaneous release of RhoGDI in primary neuronal cells. Activation of the p75NTR receptor by BNN27 reverses serum deprivation-induced apoptosis of CGNs resulting in the decrease of the phosphorylation of pro-apoptotic JNK kinase and of the cleavage of Caspase-3, effects completely abolished in CGNs, isolated from p75NTR null mice. In conclusion, BNN27 represents a lead molecule for the development of novel p75NTR ligands, controlling specific p75NTR-mediated signaling of neuronal cell fate, with potential applications in therapeutics of neurodegenerative diseases and brain trauma.
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Affiliation(s)
- Iosif Pediaditakis
- Department of Pharmacology, School of Medicine, University of CreteHeraklion, Greece; Institute of Molecular Biology and Biotechnology, Foundation of Research and Technology-HellasHeraklion, Greece
| | - Alexandra Kourgiantaki
- Department of Pharmacology, School of Medicine, University of CreteHeraklion, Greece; Institute of Molecular Biology and Biotechnology, Foundation of Research and Technology-HellasHeraklion, Greece
| | - Kyriakos C Prousis
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation Athens, Greece
| | - Constantinos Potamitis
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation Athens, Greece
| | - Kleanthis P Xanthopoulos
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation Athens, Greece
| | - Maria Zervou
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation Athens, Greece
| | - Theodora Calogeropoulou
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation Athens, Greece
| | | | - Achille Gravanis
- Department of Pharmacology, School of Medicine, University of CreteHeraklion, Greece; Institute of Molecular Biology and Biotechnology, Foundation of Research and Technology-HellasHeraklion, Greece
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Abstract
We review the evolution and structure of members of the transforming growth factor β (TGF-β) family, antagonistic or agonistic modulators, and receptors that regulate TGF-β signaling in extracellular environments. The growth factor (GF) domain common to all family members and many of their antagonists evolved from a common cystine knot growth factor (CKGF) domain. The CKGF superfamily comprises six distinct families in primitive metazoans, including the TGF-β and Dan families. Compared with Wnt/Frizzled and Notch/Delta families that also specify body axes, cell fate, tissues, and other families that contain CKGF domains that evolved in parallel, the TGF-β family was the most fruitful in evolution. Complexes between the prodomains and GFs of the TGF-β family suggest a new paradigm for regulating GF release by conversion from closed- to open-arm procomplex conformations. Ternary complexes of the final step in extracellular signaling show how TGF-β GF dimers bind type I and type II receptors on the cell surface, and enable understanding of much of the specificity and promiscuity in extracellular signaling. However, structures suggest that when GFs bind repulsive guidance molecule (RGM) family coreceptors, type I receptors do not bind until reaching an intracellular, membrane-enveloped compartment, blurring the line between extra- and intracellular signaling. Modulator protein structures show how structurally diverse antagonists including follistatins, noggin, and members of the chordin family bind GFs to regulate signaling; complexes with the Dan family remain elusive. Much work is needed to understand how these molecular components assemble to form signaling hubs in extracellular environments in vivo.
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Affiliation(s)
- Andrew P Hinck
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15260
| | - Thomas D Mueller
- Department of Plant Physiology and Biophysics, Julius-von-Sachs Institute of the University Wuerzburg, D-97082 Wuerzburg, Germany
| | - Timothy A Springer
- Program in Cellular and Molecular Medicine and Division of Hematology, Department of Medicine, Boston Children's Hospital, Boston, Massachusetts 02115
- Department of Biological Chemistry and Pharmacology, Harvard Medical School, Boston, Massachusetts 02115
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Abstract
Brain-derived neurotrophic factor (BDNF) belongs to a family of small secreted proteins that also include nerve growth factor, neurotrophin 3, and neurotrophin 4. BDNF stands out among all neurotrophins by its high expression levels in the brain and its potent effects at synapses. Several aspects of BDNF biology such as transcription, processing, and secretion are regulated by synaptic activity. Such observations prompted the suggestion that BDNF may regulate activity-dependent forms of synaptic plasticity such as long-term potentiation (LTP), a sustained enhancement of excitatory synaptic efficacy thought to underlie learning and memory. Here, we will review the evidence pointing to a fundamental role of this neurotrophin in LTP, especially within the hippocampus. Prominent questions in the field, including the release and action sites of BDNF during LTP, as well as the signaling and molecular mechanisms involved, will also be addressed. The diverse effects of BDNF at excitatory synapses are determined by the activation of TrkB receptors and downstream signaling pathways, and the functions, typically opposing in nature, of its immature form (proBDNF). The activation of p75NTR receptors by proBDNF and the implications for long-term depression will also be addressed. Finally, we discuss the synergy between TrkB and glucocorticoid receptor signaling to determine cellular responses to stress.
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Affiliation(s)
- G Leal
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - C R Bramham
- K.G. Jebsen Center for Neuropsychiatric Disorders, University of Bergen, Bergen, Norway
| | - C B Duarte
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal; University of Coimbra, Coimbra, Portugal.
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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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46
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Pramanik S, Sulistio YA, Heese K. Neurotrophin Signaling and Stem Cells-Implications for Neurodegenerative Diseases and Stem Cell Therapy. Mol Neurobiol 2016; 54:7401-7459. [PMID: 27815842 DOI: 10.1007/s12035-016-0214-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 10/11/2016] [Indexed: 02/07/2023]
Abstract
Neurotrophins (NTs) are members of a neuronal growth factor protein family whose action is mediated by the tropomyosin receptor kinase (TRK) receptor family receptors and the p75 NT receptor (p75NTR), a member of the tumor necrosis factor (TNF) receptor family. Although NTs were first discovered in neurons, recent studies have suggested that NTs and their receptors are expressed in various types of stem cells mediating pivotal signaling events in stem cell biology. The concept of stem cell therapy has already attracted much attention as a potential strategy for the treatment of neurodegenerative diseases (NDs). Strikingly, NTs, proNTs, and their receptors are gaining interest as key regulators of stem cells differentiation, survival, self-renewal, plasticity, and migration. In this review, we elaborate the recent progress in understanding of NTs and their action on various stem cells. First, we provide current knowledge of NTs, proNTs, and their receptor isoforms and signaling pathways. Subsequently, we describe recent advances in the understanding of NT activities in various stem cells and their role in NDs, particularly Alzheimer's disease (AD) and Parkinson's disease (PD). Finally, we compile the implications of NTs and stem cells from a clinical perspective and discuss the challenges with regard to transplantation therapy for treatment of AD and PD.
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Affiliation(s)
- Subrata Pramanik
- Graduate School of Biomedical Science and Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul, 133-791, Republic of Korea
| | - Yanuar Alan Sulistio
- Graduate School of Biomedical Science and Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul, 133-791, Republic of Korea
| | - Klaus Heese
- Graduate School of Biomedical Science and Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul, 133-791, Republic of Korea.
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47
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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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48
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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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Abstract
UNLABELLED The p75 neurotrophin receptor (p75(NTR)) is a multifunctional receptor that participates in many critical processes in the nervous system, ranging from apoptosis to synaptic plasticity and morphological events. It is a member of the tumor necrosis factor receptor (TNFR) superfamily, whose members undergo trimeric oligomerization. Interestingly, p75(NTR) interacts with dimeric ligands (i.e., proneurotrophins or mature neurotrophins), but several of the intracellular adaptors that mediate p75(NTR) signaling are trimeric (i.e., TNFR-associated factor 6 or TRAF6). Consequently, the active receptor signaling unit remains uncertain. To identify the functional receptor complex, we evaluated its oligomerization in vitro and in mice brain tissues using a combination of biochemical techniques. We found that the most abundant homotypic arrangement for p75(NTR) is a trimer and that monomers and trimers coexist at the cell surface. Interestingly, trimers are not required for ligand-independent or ligand-dependent p75(NTR) activation in a growth cone retraction functional assay. However, monomers are capable of inducing acute morphological effects in neurons. We propose that p75(NTR) activation is regulated by its oligomerization status and its levels of expression. These results indicate that the oligomeric state of p75(NTR) confers differential responses and offers an explanation for the diverse and contradictory actions of this receptor in the nervous system. SIGNIFICANCE STATEMENT The p75 neurotrophin receptor (p75(NTR)) regulates a wide range of cellular functions, including apoptosis, neuronal processes remodeling, and synaptic plasticity. The goal of our work was to inquire whether oligomers of the receptor are required for function. Here we report that p75(NTR) predominantly assembles as a trimer, similar to other tumor necrosis factor receptors. Interestingly, monomers and trimers coexist at the cell surface, but trimers are not required for p75(NTR) activation in a functional assay. However, monomers are capable of inducing acute morphological effects in neurons. Identification of the oligomerization state of p75(NTR) begins to provide insights to the mechanisms of signal initiation of this noncatalytic receptor, as well as to develop therapeutic interventions to diminish its activity.
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50
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Burns ML, Malott TM, Metcalf KJ, Puguh A, Chan JR, Shusta EV. Pro-region engineering for improved yeast display and secretion of brain derived neurotrophic factor. Biotechnol J 2015; 11:425-36. [PMID: 26580314 DOI: 10.1002/biot.201500360] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 08/21/2015] [Accepted: 10/19/2015] [Indexed: 11/11/2022]
Abstract
Brain derived neurotrophic factor (BDNF) is a promising therapeutic candidate for a variety of neurological diseases. However, it is difficult to produce as a recombinant protein. In its native mammalian context, BDNF is first produced as a pro-protein with subsequent proteolytic removal of the pro-region to yield mature BDNF protein. Therefore, in an attempt to improve yeast as a host for heterologous BDNF production, the BDNF pro-region was first evaluated for its effects on BDNF surface display and secretion. Addition of the wild-type pro-region to yeast BDNF production constructs improved BDNF folding both as a surface-displayed and secreted protein in terms of binding its natural receptors TrkB and p75, but titers remained low. Looking to further enhance the chaperone-like functions provided by the pro-region, two rounds of directed evolution were performed, yielding mutated pro-regions that further improved the display and secretion properties of BDNF. Subsequent optimization of the protease recognition site was used to control whether the produced protein was in pro- or mature BDNF forms. Taken together, we have demonstrated an effective strategy for improving BDNF compatibility with yeast protein engineering and secretion platforms.
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Affiliation(s)
- Michael L Burns
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Thomas M Malott
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Kevin J Metcalf
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Arthya Puguh
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Jonah R Chan
- Department of Neurology, Program in Neuroscience, University of California, San Francisco, San Francisco, California, USA
| | - Eric V Shusta
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin, USA.
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