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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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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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3
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VPS10P Domain Receptors: Sorting Out Brain Health and Disease. Trends Neurosci 2020; 43:870-885. [DOI: 10.1016/j.tins.2020.08.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 07/23/2020] [Accepted: 08/11/2020] [Indexed: 12/13/2022]
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4
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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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5
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Zamani M, Eslami M, Nezafat N, Hosseini SV, Ghasemi Y. Evaluating the effect of BDNF Val66Met polymorphism on complex formation with HAP1 and Sortilin1 via structural modeling. Comput Biol Chem 2019; 78:282-289. [PMID: 30602138 DOI: 10.1016/j.compbiolchem.2018.12.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 12/24/2018] [Accepted: 12/24/2018] [Indexed: 10/27/2022]
Abstract
Brain derived neurotrophic factor (BDNF) has a critical role in the neurogenesis, differentiation, survival of the neurons, regulation of the appetite, and energy homeostasis. Two key proteins, Huntingtin associated protein-1 (HAP1) and sortilin1, regulate the intracellular trafficking and stabilization of the precursor proBDNF through interaction with its prodomain region and mark it for secretion. Evidence suggests that the most frequent single nucleotide polymorphism (SNP) of BDNF gene (rs6265) has been associated with different psychiatric, neurodegenerative and eating disorders. In this study, structural bioinformatics and molecular dynamics (MD) simulations were applied, in order to get precise insights into the impact of Val66Met polymorphism on the proBDNF structure and its interaction with HAP1 and Sortilin1. Homology modeling, structure validation, refinement and also protein-protein docking were performed using appropriate servers. The stability, the fluctuations and the compactness of protein complexes were measured by MD simulation parameters including root mean square deviation (RMSD), root mean square fluctuation (RMSF) and Radius of gyration (Rg), respectively. The mutant proBDNF complexes with HAP1 and Sortilin1 revealed higher RMSD and RMSF values and also variable Rg over time compared with wild-type proBDNF. These computational results indicated that, wild-type proBDNF possessed more stable structure in binding with HAP1 and Sortilin1 compared with its mutant form. Therefore, Val66Met SNP could be deleterious due to making structural changes. It may cause a decrease in proBDNF secretion, which could possibly lead to different psychiatric, neurodegenerative and eating disorders. Further experimental lab studies are required for a more accurate conclusion.
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Affiliation(s)
- Mozhdeh Zamani
- Colorectal Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mahboobeh Eslami
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Science, Shiraz, Iran
| | - Navid Nezafat
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Science, Shiraz, Iran; Department of Pharmaceutical Biotechnology, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz, Iran.
| | | | - Younes Ghasemi
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Science, Shiraz, Iran; Department of Pharmaceutical Biotechnology, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz, Iran; Department of Medical Biotechnology, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran.
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6
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Goettsch C, Kjolby M, Aikawa E. Sortilin and Its Multiple Roles in Cardiovascular and Metabolic Diseases. Arterioscler Thromb Vasc Biol 2017; 38:19-25. [PMID: 29191923 DOI: 10.1161/atvbaha.117.310292] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 11/16/2017] [Indexed: 12/24/2022]
Abstract
Cardiovascular disease is a leading cause of morbidity and mortality in the Western world. Studies of sortilin's influence on cardiovascular and metabolic diseases goes far beyond the genome-wide association studies that have revealed an association between cardiovascular diseases and the 1p13 locus that encodes sortilin. Emerging evidence suggests a significant role of sortilin in the pathogenesis of vascular and metabolic diseases; this includes type II diabetes mellitus via regulation of insulin resistance, atherosclerosis through arterial wall inflammation and calcification, and dysregulated lipoprotein metabolism. Sortilin is also known for its functional role in neurological disorders. It serves as a key receptor for cytokines, lipids, and enzymes and participates in pathological cargo loading to and trafficking of extracellular vesicles. This article provides a comprehensive review of sortilin's contributions to cardiovascular and metabolic diseases but focuses particularly on atherosclerosis. We summarize recent clinical findings that suggest that sortilin may be a cardiovascular risk biomarker and also discuss sortilin as a potential drug target.
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Affiliation(s)
- Claudia Goettsch
- From the Department of Internal Medicine I-Cardiology, RWTH Aachen University, Germany (C.G.); The Danish Research Institute of Translational Neuroscience, Nordic European Molecular Biology Laboratory Partnership for Molecular Medicine, Danish Diabetes Academy, Denmark (M.K.); Department of Biomedicine (M.K.) and Department of Cardiology (M.K.), Aarhus University, Denmark; and Center for Interdisciplinary Cardiovascular Sciences (E.A.) and Center for Excellence in Vascular Biology, Division of Cardiovascular Medicine (E.A.), Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Mads Kjolby
- From the Department of Internal Medicine I-Cardiology, RWTH Aachen University, Germany (C.G.); The Danish Research Institute of Translational Neuroscience, Nordic European Molecular Biology Laboratory Partnership for Molecular Medicine, Danish Diabetes Academy, Denmark (M.K.); Department of Biomedicine (M.K.) and Department of Cardiology (M.K.), Aarhus University, Denmark; and Center for Interdisciplinary Cardiovascular Sciences (E.A.) and Center for Excellence in Vascular Biology, Division of Cardiovascular Medicine (E.A.), Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Elena Aikawa
- From the Department of Internal Medicine I-Cardiology, RWTH Aachen University, Germany (C.G.); The Danish Research Institute of Translational Neuroscience, Nordic European Molecular Biology Laboratory Partnership for Molecular Medicine, Danish Diabetes Academy, Denmark (M.K.); Department of Biomedicine (M.K.) and Department of Cardiology (M.K.), Aarhus University, Denmark; and Center for Interdisciplinary Cardiovascular Sciences (E.A.) and Center for Excellence in Vascular Biology, Division of Cardiovascular Medicine (E.A.), Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
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7
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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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8
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PROneurotrophins and CONSequences. Mol Neurobiol 2017; 55:2934-2951. [DOI: 10.1007/s12035-017-0505-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 03/21/2017] [Indexed: 01/12/2023]
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9
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Carlo AS, Nykjaer A, Willnow TE. Sorting receptor sortilin-a culprit in cardiovascular and neurological diseases. J Mol Med (Berl) 2014; 92:905-11. [PMID: 24838608 DOI: 10.1007/s00109-014-1152-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 02/19/2014] [Indexed: 11/30/2022]
Abstract
Sortilin is a sorting receptor that directs target proteins, such as growth factors, signaling receptors, and enzymes, to their destined location in secretory or endocytic compartments of cells. The activity of sortilin is essential for proper function of not only neurons but also non-neuronal cell types, and receptor (dys)function emerges as a major cause of malignancies, including hypercholesterolemia, retinal degeneration, neuronal cell loss in stroke and spinal cord injury, or Alzheimer's disease and other neurodegenerative disorders. In this article, we describe the molecular mechanisms of sortilin action in protein sorting and signaling and how modulation of receptor function may offer novel therapeutic strategies for treatment of common diseases of the cardiovascular and nervous systems.
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Affiliation(s)
- Anne-Sophie Carlo
- Max-Delbrueck-Center for Molecular Medicine, Robert-Roessle-Strasse 10, 13125, Berlin, Germany
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10
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Small-molecule modulation of neurotrophin receptors: a strategy for the treatment of neurological disease. Nat Rev Drug Discov 2013; 12:507-25. [PMID: 23977697 DOI: 10.1038/nrd4024] [Citation(s) in RCA: 198] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Neurotrophins and their receptors modulate multiple signalling pathways to regulate neuronal survival and to maintain axonal and dendritic networks and synaptic plasticity. Neurotrophins have potential for the treatment of neurological diseases. However, their therapeutic application has been limited owing to their poor plasma stability, restricted nervous system penetration and, importantly, the pleiotropic actions that derive from their concomitant binding to multiple receptors. One strategy to overcome these limitations is to target individual neurotrophin receptors — such as tropomyosin receptor kinase A (TRKA), TRKB, TRKC, the p75 neurotrophin receptor or sortilin — with small-molecule ligands. Such small molecules might also modulate various aspects of these signalling pathways in ways that are distinct from the programmes triggered by native neurotrophins. By departing from conventional neurotrophin signalling, these ligands might provide novel therapeutic options for a broad range of neurological indications.
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11
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Sloves PJ, Delhaye S, Mouveaux T, Werkmeister E, Slomianny C, Hovasse A, Dilezitoko Alayi T, Callebaut I, Gaji R, Schaeffer-Reiss C, Van Dorsselear A, Carruthers V, Tomavo S. Toxoplasma Sortilin-like Receptor Regulates Protein Transport and Is Essential for Apical Secretory Organelle Biogenesis and Host Infection. Cell Host Microbe 2012; 11:515-27. [DOI: 10.1016/j.chom.2012.03.006] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Revised: 02/02/2012] [Accepted: 03/28/2012] [Indexed: 12/16/2022]
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12
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Sortilin participates in light-dependent photoreceptor degeneration in vivo. PLoS One 2012; 7:e36243. [PMID: 22558402 PMCID: PMC3338683 DOI: 10.1371/journal.pone.0036243] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2011] [Accepted: 04/03/2012] [Indexed: 11/20/2022] Open
Abstract
Both proNGF and the neurotrophin receptor p75 (p75NTR) are known to regulate photoreceptor cell death caused by exposure of albino mice to intense illumination. ProNGF-induced apoptosis requires the participation of sortilin as a necessary p75NTR co-receptor, suggesting that sortilin may participate in the photoreceptor degeneration triggered by intense lighting. We report here that light-exposed albino mice showed sortilin, p75NTR, and proNGF expression in the outer nuclear layer, the retinal layer where photoreceptor cell bodies are located. In addition, cone progenitor-derived 661W cells subjected to intense illumination expressed sortilin and p75NTR and released proNGF into the culture medium. Pharmacological blockade of sortilin with either neurotensin or the “pro” domain of proNGF (pro-peptide) favored the survival of 661W cells subjected to intense light. In vivo, the pro-peptide attenuated retinal cell death in light-exposed albino mice. We propose that an auto/paracrine proapoptotic mechanism based on the interaction of proNGF with the receptor complex p75NTR/sortilin participates in intense light-dependent photoreceptor cell death. We therefore propose sortilin as a putative target for intervention in hereditary retinal dystrophies.
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Nykjaer A, Willnow TE. Sortilin: a receptor to regulate neuronal viability and function. Trends Neurosci 2012; 35:261-70. [DOI: 10.1016/j.tins.2012.01.003] [Citation(s) in RCA: 149] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Revised: 01/08/2012] [Accepted: 01/10/2012] [Indexed: 11/26/2022]
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Prediction of B-cell linear epitopes with a combination of support vector machine classification and amino acid propensity identification. J Biomed Biotechnol 2011; 2011:432830. [PMID: 21876642 PMCID: PMC3163029 DOI: 10.1155/2011/432830] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Accepted: 06/28/2011] [Indexed: 12/29/2022] Open
Abstract
Epitopes are antigenic determinants that are useful because they induce B-cell antibody production and stimulate T-cell activation. Bioinformatics can enable rapid, efficient prediction of potential epitopes. Here, we designed a novel B-cell linear epitope prediction system called LEPS, Linear Epitope Prediction by Propensities and Support Vector Machine, that combined physico-chemical propensity identification and support vector machine (SVM) classification. We tested the LEPS on four datasets: AntiJen, HIV, a newly generated PC, and AHP, a combination of these three datasets. Peptides with globally or locally high physicochemical propensities were first identified as primitive linear epitope (LE) candidates. Then, candidates were classified with the SVM based on the unique features of amino acid segments. This reduced the number of predicted epitopes and enhanced the positive prediction value (PPV). Compared to four other well-known LE prediction systems, the LEPS achieved the highest accuracy (72.52%), specificity (84.22%), PPV (32.07%), and Matthews' correlation coefficient (10.36%).
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15
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Zheng Y, Brady OA, Meng PS, Mao Y, Hu F. C-terminus of progranulin interacts with the beta-propeller region of sortilin to regulate progranulin trafficking. PLoS One 2011; 6:e21023. [PMID: 21698296 PMCID: PMC3115958 DOI: 10.1371/journal.pone.0021023] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Accepted: 05/17/2011] [Indexed: 12/29/2022] Open
Abstract
Progranulin haplo-insufficiency is a main cause of frontotemporal lobar degeneration (FTLD) with TDP-43 aggregates. Previous studies have shown that sortilin regulates progranulin trafficking and is a main determinant of progranulin level in the brain. In this study, we mapped the binding site between progranulin and sortilin. Progranulin binds to the beta-propeller region of sortilin through its C-terminal tail. The C-terminal progranulin fragment is fully sufficient for sortilin binding and progranulin C-terminal peptide displaces progranulin binding to sortilin. Deletion of the last 3 residues of progranulin (QLL) abolishes its binding to sortilin and also sortilin dependent regulation of progranulin trafficking. Since progranulin haplo-insufficiency results in FTLD, these results may provide important insights into future studies of progranulin trafficking and signaling and progranulin based therapy for FTLD.
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Affiliation(s)
- Yanqiu Zheng
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, United States of America
| | - Owen A. Brady
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, United States of America
| | - Peter S. Meng
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, United States of America
| | - Yuxin Mao
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, United States of America
| | - Fenghua Hu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, United States of America
- * E-mail:
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