1
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Mitok KA, Schueler KL, King SM, Orr J, Ryan KA, Keller MP, Krauss RM, Mitchell BD, Shuldiner AR, Attie AD. Missense variants in SORT1 are associated with LDL-C in an Amish population. J Lipid Res 2023; 64:100468. [PMID: 37913995 PMCID: PMC10711479 DOI: 10.1016/j.jlr.2023.100468] [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: 08/09/2023] [Revised: 10/23/2023] [Accepted: 10/26/2023] [Indexed: 11/03/2023] Open
Abstract
Common noncoding variants at the human 1p13.3 locus associated with SORT1 expression are among those most strongly associated with low-density lipoprotein cholesterol (LDL-C) in human genome-wide association studies. However, validation studies in mice and cell lines have produced variable results regarding the directionality of the effect of SORT1 on LDL-C. This, together with the fact that the 1p13.3 variants are associated with expression of several genes, has raised the question of whether SORT1 is the causal gene at this locus. Using whole exome sequencing in members of an Amish population, we identified coding variants in SORT1 that are associated with increased (rs141749679, K302E) and decreased (rs149456022, Q225H) LDL-C. Further, analysis of plasma lipoprotein particle subclasses by ion mobility in a subset of rs141749679 (K302E) carriers revealed higher levels of large LDL particles compared to noncarriers. In contrast to the effect of these variants in the Amish, the sortilin K302E mutation introduced into a C57BL/6J mouse via CRISPR/Cas9 resulted in decreased non-high-density lipoprotein cholesterol, and the sortilin Q225H mutation did not alter cholesterol levels in mice. This is indicative of different effects of these mutations on cholesterol metabolism in the two species. To our knowledge, this is the first evidence that naturally occurring coding variants in SORT1 are associated with LDL-C, thus supporting SORT1 as the gene responsible for the association of the 1p13.3 locus with LDL-C.
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Affiliation(s)
- Kelly A Mitok
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Kathryn L Schueler
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Sarah M King
- Department of Pediatrics, University of California-San Francisco, San Francisco, CA, USA
| | - Joseph Orr
- Department of Pediatrics, University of California-San Francisco, San Francisco, CA, USA
| | - Kathleen A Ryan
- Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Mark P Keller
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Ronald M Krauss
- Department of Pediatrics, University of California-San Francisco, San Francisco, CA, USA
| | - Braxton D Mitchell
- Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Alan R Shuldiner
- Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA; Regeneron Genetics Center, Tarrytown, NY, USA
| | - Alan D Attie
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA.
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2
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Leppert HG, Anderson JT, Timm KJ, Davoli C, Pratt MA, Booth CD, White KA, Rechtzigel MJ, Meyerink BL, Johnson TB, Brudvig JJ, Weimer JM. Sortilin inhibition treats multiple neurodegenerative lysosomal storage disorders. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.22.559064. [PMID: 37790379 PMCID: PMC10543011 DOI: 10.1101/2023.09.22.559064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Lysosomal storage disorders (LSDs) are a genetically and clinically diverse group of diseases characterized by lysosomal dysfunction. Batten disease is a family of severe LSDs primarily impacting the central nervous system. Here we show that AF38469, a small molecule inhibitor of sortilin, improves lysosomal and glial pathology across multiple LSD models. Live-cell imaging and comparative transcriptomics demonstrates that the transcription factor EB (TFEB), an upstream regulator of lysosomal biogenesis, is activated upon treatment with AF38469. Utilizing CLN2 and CLN3 Batten disease mouse models, we performed a short-term efficacy study and show that treatment with AF38469 prevents the accumulation of lysosomal storage material and the development of neuroinflammation, key disease associated pathologies. Tremor phenotypes, an early behavioral phenotype in the CLN2 disease model, were also completely rescued. These findings reveal sortilin inhibition as a novel and highly efficacious therapeutic modality for the treatment of multiple forms of Batten disease.
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Affiliation(s)
- Hannah G. Leppert
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD
| | | | - Kaylie J. Timm
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD
| | - Cristina Davoli
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD
| | - Melissa A. Pratt
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD
| | - Clarissa D. Booth
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD
| | | | | | | | - Tyler B. Johnson
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD
| | - Jon J. Brudvig
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD
- Department of Pediatrics, Sanford School of Medicine, University of South Dakota, Sioux Falls, SD, USA
| | - Jill M. Weimer
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD
- Department of Pediatrics, Sanford School of Medicine, University of South Dakota, Sioux Falls, SD, USA
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3
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Huang B, Abedi M, Ahn G, Coventry B, Sappington I, Wang R, Schlichthaerle T, Zhang JZ, Wang Y, Goreshnik I, Chiu CW, Chazin-Gray A, Chan S, Gerben S, Murray A, Wang S, O'Neill J, Yeh R, Misquith A, Wolf A, Tomasovic LM, Piraner DI, Gonzalez MJD, Bennett NR, Venkatesh P, Satoe D, Ahlrichs M, Dobbins C, Yang W, Wang X, Vafeados D, Mout R, Shivaei S, Cao L, Carter L, Stewart L, Spangler JB, Bernardes GJL, Roybal KT, Greisen P, Li X, Bertozzi C, Baker D. Designed Endocytosis-Triggering Proteins mediate Targeted Degradation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.19.553321. [PMID: 37781607 PMCID: PMC10541094 DOI: 10.1101/2023.08.19.553321] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/03/2023]
Abstract
Endocytosis and lysosomal trafficking of cell surface receptors can be triggered by interaction with endogenous ligands. Therapeutic approaches such as LYTAC1,2 and KineTAC3, have taken advantage of this to target specific proteins for degradation by fusing modified native ligands to target binding proteins. While powerful, these approaches can be limited by possible competition with the endogenous ligand(s), the requirement in some cases for chemical modification that limits genetic encodability and can complicate manufacturing, and more generally, there may not be natural ligands which stimulate endocytosis through a given receptor. Here we describe general protein design approaches for designing endocytosis triggering binding proteins (EndoTags) that overcome these challenges. We present EndoTags for the IGF-2R, ASGPR, Sortillin, and Transferrin receptors, and show that fusing these tags to proteins which bind to soluble or transmembrane protein leads to lysosomal trafficking and target degradation; as these receptors have different tissue distributions, the different EndoTags could enable targeting of degradation to different tissues. The modularity and genetic encodability of EndoTags enables AND gate control for higher specificity targeted degradation, and the localized secretion of degraders from engineered cells. The tunability and modularity of our genetically encodable EndoTags should contribute to deciphering the relationship between receptor engagement and cellular trafficking, and they have considerable therapeutic potential as targeted degradation inducers, signaling activators for endocytosis-dependent pathways, and cellular uptake inducers for targeted antibody drug and RNA conjugates.
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Affiliation(s)
- Buwei Huang
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Mohamad Abedi
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Green Ahn
- Department of Chemistry, Stanford University, Stanford, CA, USA
| | - Brian Coventry
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
- Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA
| | - Isaac Sappington
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Rong Wang
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Thomas Schlichthaerle
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Jason Z Zhang
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Yujia Wang
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Inna Goreshnik
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
- Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA
| | - Ching Wen Chiu
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Adam Chazin-Gray
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Sidney Chan
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Stacey Gerben
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Analisa Murray
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Shunzhi Wang
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | | | | | | | | | - Luke M Tomasovic
- Departments of Biomedical Engineering and Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, USA
- Medical Scientist Training Program, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Dan I Piraner
- Department of Microbiology and Immunology, University of California San Francisco
| | | | - Nathaniel R Bennett
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Preetham Venkatesh
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Danny Satoe
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Maggie Ahlrichs
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Craig Dobbins
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Wei Yang
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Xinru Wang
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Dionne Vafeados
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Rubul Mout
- Harvard Medical School, Harvard University, Boston, Massachusetts, USA
| | - Shirin Shivaei
- Division of Biology and Bioengineering, California Institute of Technology, Pasadena, CA, USA
| | - Longxing Cao
- School of Life Sciences, Westlake University, Hangzhou, China
| | - Lauren Carter
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Lance Stewart
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Jamie B Spangler
- Departments of Biomedical Engineering and Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Gonçalo J L Bernardes
- Division of Biology and Bioengineering, California Institute of Technology, Pasadena, CA, USA
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Kole T Roybal
- Department of Microbiology and Immunology, University of California San Francisco
| | | | - Xiaochun Li
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Carolyn Bertozzi
- Department of Chemistry, Stanford University, Stanford, CA, USA
- Division of Biology and Bioengineering, California Institute of Technology, Pasadena, CA, USA
- Sarafan ChEM-H, Stanford University, Stanford, CA 94305, USA
| | - David Baker
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
- Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA
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4
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Athiyarath V, Mathew LA, Zhao Y, Khazeber R, Ramamurty U, Sureshan KM. Rational design and topochemical synthesis of polymorphs of a polymer. Chem Sci 2023; 14:5132-5140. [PMID: 37206383 PMCID: PMC10189859 DOI: 10.1039/d3sc00053b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 04/13/2023] [Indexed: 05/21/2023] Open
Abstract
Packing a polymer in different ways can give polymorphs of the polymer having different properties. β-Turn forming peptides such as 2-aminoisobutyric acid (Aib)-rich peptides adopt several conformations by varying the dihedral angles. Aiming at this, a β-turn-forming peptide monomer would give different polymorphs and these polymorphs upon topochemical polymerization would yield polymorphs of the polymer, we designed an Aib-rich monomer N3-(Aib)3-NHCH2-C[triple bond, length as m-dash]CH. This monomer crystallizes as two polymorphs and one hydrate. In all forms, the peptide adopts β-turn conformations and arranges in a head-to-tail manner with their azide and alkyne units proximally placed in a ready-to-react alignment. On heating, both the polymorphs undergo topochemical azide-alkyne cycloaddition polymerization. Polymorph I polymerized in a single-crystal-to-single-crystal (SCSC) fashion and the single-crystal X-ray diffraction analysis of the polymer revealed its screw-sense reversing helical structure. Polymorph II maintains its crystallinity during polymerization but gradually becomes amorphous upon storage. The hydrate III undergoes a dehydrative transition to polymorph II. Nanoindentation studies revealed that different polymorphs of the monomer and the corresponding polymers exhibited different mechanical properties, in accordance with their crystal packing. This work demonstrates the promising future of the marriage of polymorphism and topochemistry for obtaining polymorphs of polymers.
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Affiliation(s)
- Vignesh Athiyarath
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram Kerala 695551 India
| | - Liby Ann Mathew
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram Kerala 695551 India
| | - Yakai Zhao
- School of Mechanical and Aerospace Engineering, Nanyang Technological University 639798 Singapore
| | - Ravichandran Khazeber
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram Kerala 695551 India
| | - Upadrasta Ramamurty
- School of Mechanical and Aerospace Engineering, Nanyang Technological University 639798 Singapore
| | - Kana M Sureshan
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram Kerala 695551 India
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5
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Rodríguez FD, Sánchez ML, Coveñas R. Neurotensin and Alcohol Use Disorders: Towards a Pharmacological Treatment. Int J Mol Sci 2023; 24:ijms24108656. [PMID: 37240004 DOI: 10.3390/ijms24108656] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/06/2023] [Accepted: 05/10/2023] [Indexed: 05/28/2023] Open
Abstract
Harmful alcohol use is responsible for a group of disorders collectively named alcohol use disorders (AUDs), according to the DSM-5 classification. The damage induced by alcohol depends on the amount, time, and consumption patterns (continuous and heavy episodic drinking). It affects individual global well-being and social and familial environments with variable impact. Alcohol addiction manifests with different degrees of organ and mental health detriment for the individual, exhibiting two main traits: compulsive drinking and negative emotional states occurring at withdrawal, frequently causing relapse episodes. Numerous individual and living conditions, including the concomitant use of other psychoactive substances, lie in the complexity of AUD. Ethanol and its metabolites directly impact the tissues and may cause local damage or alter the homeostasis of brain neurotransmission, immunity scaffolding, or cell repair biochemical pathways. Brain modulator and neurotransmitter-assembled neurocircuitries govern reward, reinforcement, social interaction, and consumption of alcohol behaviors in an intertwined manner. Experimental evidence supports the participation of neurotensin (NT) in preclinical models of alcohol addiction. For example, NT neurons in the central nucleus of the amygdala projecting to the parabrachial nucleus strengthen alcohol consumption and preference. In addition, the levels of NT in the frontal cortex were found to be lower in rats bred to prefer alcohol to water in a free alcohol-water choice compared to wild-type animals. NT receptors 1 and 2 seem to be involved in alcohol consumption and alcohol effects in several models of knockout mice. This review aims to present an updated picture of the role of NT systems in alcohol addiction and the possible use of nonpeptide ligands modulating the activity of the NT system, applied to experimental animal models of harmful drinking behavior mimicking alcohol addiction leading to health ruin in humans.
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Affiliation(s)
- Francisco D Rodríguez
- Department of Biochemistry and Molecular Biology, Faculty of Chemical Sciences, University of Salamanca, 37008 Salamanca, Spain
- Group GIR-USAL: BMD (Bases Moleculares del Desarrollo), University of Salamanca, 37008 Salamanca, Spain
| | - Manuel Lisardo Sánchez
- Laboratory of Neuroanatomy of the Peptidergic Systems, Institute of Neurosciences of Castilla and León (INCYL), University of Salamanca, C/Pintor Fernando Gallego 1, 37007 Salamanca, Spain
| | - Rafael Coveñas
- Group GIR-USAL: BMD (Bases Moleculares del Desarrollo), University of Salamanca, 37008 Salamanca, Spain
- Laboratory of Neuroanatomy of the Peptidergic Systems, Institute of Neurosciences of Castilla and León (INCYL), University of Salamanca, C/Pintor Fernando Gallego 1, 37007 Salamanca, Spain
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6
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Avvisato R, Jankauskas SS, Varzideh F, Kansakar U, Mone P, Santulli G. Sortilin and hypertension. Curr Opin Nephrol Hypertens 2023; 32:134-140. [PMID: 36683537 PMCID: PMC9976622 DOI: 10.1097/mnh.0000000000000866] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
PURPOSE OF REVIEW The current review aims to present the latest scientific updates on the role of Sortilin in the pathophysiology of hypertension. RECENT FINDINGS The main focus of this systematic overview is on the functional contribution of Sortilin to the pathogenesis of hypertension. Sortilin is a glycoprotein mostly known for its actions as a trafficking molecule directing proteins to specific secretory or endocytic compartments of the cell. Emerging evidence indicates that Sortilin is associated with pathological conditions, including inflammation, arteriosclerosis, dyslipidemia, insulin resistance, and vascular calcification. Most recently, Sortilin has been shown to finely control endothelial function and to drive hypertension by modulating sphingolipid/ceramide homeostasis and by triggering oxidative stress. SUMMARY The latest findings linking Sortilin and hypertension that are herein discussed can inspire novel areas of research which could eventually lead to the discovery of new therapeutic strategies in cardiovascular medicine.
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Affiliation(s)
- Roberta Avvisato
- Department of Medicine, Division of Cardiology, Wilf Family Cardiovascular Research Institute, Einstein Institute for Aging Research and
- Department of Molecular Pharmacology, Einstein-Mount Sinai Diabetes Research Center (ES-DRC), Fleischer Institute for Diabetes and Metabolism (FIDAM), Institute for Neuroimmunology and Inflammation, Albert Einstein College of Medicine, New York, New York, USA
| | - Stanislovas S. Jankauskas
- Department of Medicine, Division of Cardiology, Wilf Family Cardiovascular Research Institute, Einstein Institute for Aging Research and
- Department of Molecular Pharmacology, Einstein-Mount Sinai Diabetes Research Center (ES-DRC), Fleischer Institute for Diabetes and Metabolism (FIDAM), Institute for Neuroimmunology and Inflammation, Albert Einstein College of Medicine, New York, New York, USA
| | - Fahimeh Varzideh
- Department of Medicine, Division of Cardiology, Wilf Family Cardiovascular Research Institute, Einstein Institute for Aging Research and
- Department of Molecular Pharmacology, Einstein-Mount Sinai Diabetes Research Center (ES-DRC), Fleischer Institute for Diabetes and Metabolism (FIDAM), Institute for Neuroimmunology and Inflammation, Albert Einstein College of Medicine, New York, New York, USA
| | - Urna Kansakar
- Department of Medicine, Division of Cardiology, Wilf Family Cardiovascular Research Institute, Einstein Institute for Aging Research and
- Department of Molecular Pharmacology, Einstein-Mount Sinai Diabetes Research Center (ES-DRC), Fleischer Institute for Diabetes and Metabolism (FIDAM), Institute for Neuroimmunology and Inflammation, Albert Einstein College of Medicine, New York, New York, USA
| | - Pasquale Mone
- Department of Medicine, Division of Cardiology, Wilf Family Cardiovascular Research Institute, Einstein Institute for Aging Research and
- Department of Molecular Pharmacology, Einstein-Mount Sinai Diabetes Research Center (ES-DRC), Fleischer Institute for Diabetes and Metabolism (FIDAM), Institute for Neuroimmunology and Inflammation, Albert Einstein College of Medicine, New York, New York, USA
| | - Gaetano Santulli
- Department of Medicine, Division of Cardiology, Wilf Family Cardiovascular Research Institute, Einstein Institute for Aging Research and
- Department of Molecular Pharmacology, Einstein-Mount Sinai Diabetes Research Center (ES-DRC), Fleischer Institute for Diabetes and Metabolism (FIDAM), Institute for Neuroimmunology and Inflammation, Albert Einstein College of Medicine, New York, New York, USA
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7
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Dimerization of the Alzheimer's disease pathogenic receptor SORLA regulates its association with retromer. Proc Natl Acad Sci U S A 2023; 120:e2212180120. [PMID: 36652482 PMCID: PMC9942828 DOI: 10.1073/pnas.2212180120] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
SORL1, the gene encoding the large multidomain SORLA protein, has emerged as only the fourth gene that when mutated can by itself cause Alzheimer's disease (AD), and as a gene reliably linked to both the early- and late-onset forms of the disease. SORLA is known to interact with the endosomal trafficking regulatory complex called retromer in regulating the recycling of endosomal cargo, including the amyloid precursor protein (APP) and the glutamate receptor GluA1. Nevertheless, SORLA's precise structural-functional relationship in endosomal recycling tubules remains unknown. Here, we address these outstanding questions by relying on crystallographic and artificial-intelligence evidence to generate a structural model for how SORLA folds and fits into retromer-positive endosomal tubules, where it is found to dimerize via both SORLA's fibronectin-type-III (3Fn)- and VPS10p-domains. Moreover, we identify a SORLA fragment comprising the 3Fn-, transmembrane, and cytoplasmic domains that has the capacity to form a dimer, and to enhance retromer-dependent recycling of APP by decreasing its amyloidogenic processing. Collectively, these observations generate a model for how SORLA dimer (and possibly polymer) formation can function in stabilizing and enhancing retromer function at endosome tubules. These findings can inform investigation of the many AD-associated SORL1 variants for evidence of pathogenicity and can guide discovery of novel drugs for the disease.
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8
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Salasova A, Monti G, Andersen OM, Nykjaer A. Finding memo: versatile interactions of the VPS10p-Domain receptors in Alzheimer’s disease. Mol Neurodegener 2022; 17:74. [PMID: 36397124 PMCID: PMC9673319 DOI: 10.1186/s13024-022-00576-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Accepted: 10/17/2022] [Indexed: 11/19/2022] Open
Abstract
The family of VPS10p-Domain (D) receptors comprises five members named SorLA, Sortilin, SorCS1, SorCS2 and SorCS3. While their physiological roles remain incompletely resolved, they have been recognized for their signaling engagements and trafficking abilities, navigating a number of molecules between endosome, Golgi compartments, and the cell surface. Strikingly, recent studies connected all the VPS10p-D receptors to Alzheimer’s disease (AD) development. In addition, they have been also associated with diseases comorbid with AD such as diabetes mellitus and major depressive disorder. This systematic review elaborates on genetic, functional, and mechanistic insights into how dysfunction in VPS10p-D receptors may contribute to AD etiology, AD onset diversity, and AD comorbidities. Starting with their functions in controlling cellular trafficking of amyloid precursor protein and the metabolism of the amyloid beta peptide, we present and exemplify how these receptors, despite being structurally similar, regulate various and distinct cellular events involved in AD. This includes a plethora of signaling crosstalks that impact on neuronal survival, neuronal wiring, neuronal polarity, and synaptic plasticity. Signaling activities of the VPS10p-D receptors are especially linked, but not limited to, the regulation of neuronal fitness and apoptosis via their physical interaction with pro- and mature neurotrophins and their receptors. By compiling the functional versatility of VPS10p-D receptors and their interactions with AD-related pathways, we aim to further propel the AD research towards VPS10p-D receptor family, knowledge that may lead to new diagnostic markers and therapeutic strategies for AD patients.
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9
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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: 16] [Impact Index Per Article: 8.0] [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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10
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Wang S, Jiang Q, Loor JJ, Gao C, Yang M, Tian Y, Fan W, Zhang B, Li M, Xu C, Yang W. Role of sortilin 1 (SORT1) on fatty acid–mediated cholesterol metabolism in primary calf hepatocytes. J Dairy Sci 2022; 105:7773-7786. [DOI: 10.3168/jds.2022-22108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 05/20/2022] [Indexed: 11/19/2022]
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11
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Eising S, Esch B, Wälte M, Vargas Duarte P, Walter S, Ungermann C, Bohnert M, Fröhlich F. A lysosomal biogenesis map reveals the cargo spectrum of yeast vacuolar protein targeting pathways. J Cell Biol 2022; 221:213011. [PMID: 35175277 PMCID: PMC8859911 DOI: 10.1083/jcb.202107148] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 12/20/2021] [Accepted: 01/18/2022] [Indexed: 12/15/2022] Open
Abstract
The lysosome is the major catabolic organelle in the cell that has been established as a key metabolic signaling center. Mutations in many lysosomal proteins have catastrophic effects and cause neurodegeneration, cancer, and age-related diseases. The vacuole is the lysosomal analog of Saccharomyces cerevisiae that harbors many evolutionary conserved proteins. Proteins reach vacuoles via the Vps10-dependent endosomal vacuolar protein sorting pathway, via the alkaline phosphatase (ALP or AP-3) pathway, and via the cytosol-to-vacuole transport (CVT) pathway. A systematic understanding of the cargo spectrum of each pathway is completely lacking. Here, we use quantitative proteomics of purified vacuoles to generate the yeast lysosomal biogenesis map. This dataset harbors information on the cargo-receptor relationship of almost all vacuolar proteins. We map binding motifs of Vps10 and the AP-3 complex and identify a novel cargo of the CVT pathway under nutrient-rich conditions. Our data show how organelle purification and quantitative proteomics can uncover fundamental insights into organelle biogenesis.
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Affiliation(s)
- Sebastian Eising
- Molecular Membrane Biology Group, Department of Biology/Chemistry, Osnabrück University, Osnabrück, Germany
| | - Bianca Esch
- Molecular Membrane Biology Group, Department of Biology/Chemistry, Osnabrück University, Osnabrück, Germany
| | - Mike Wälte
- Institute of Cell Dynamics and Imaging, University of Münster, Münster, Germany
| | - Prado Vargas Duarte
- Biochemistry Section, Department of Biology/Chemistry, Osnabrück University, Osnabrück, Germany
| | - Stefan Walter
- Center of Cellular Nanoanalytics Osnabrück, Osnabrück University, Osnabrück, Germany
| | - Christian Ungermann
- Biochemistry Section, Department of Biology/Chemistry, Osnabrück University, Osnabrück, Germany.,Center of Cellular Nanoanalytics Osnabrück, Osnabrück University, Osnabrück, Germany
| | - Maria Bohnert
- Institute of Cell Dynamics and Imaging, University of Münster, Münster, Germany.,Cells in Motion Interfaculty Centre, University of Münster, Münster, Germany
| | - Florian Fröhlich
- Molecular Membrane Biology Group, Department of Biology/Chemistry, Osnabrück University, Osnabrück, Germany.,Biochemistry Section, Department of Biology/Chemistry, Osnabrück University, Osnabrück, Germany
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12
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Cryo-EM structures reveal distinct apo conformations of sortilin-related receptor SORLA. Biochem Biophys Res Commun 2022; 600:75-79. [DOI: 10.1016/j.bbrc.2022.01.108] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Accepted: 01/26/2022] [Indexed: 01/12/2023]
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13
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Artemieva LE, Mineev KS, Arseniev AS, Goncharuk SA. Expression, purification and characterization of SORCS2 intracellular domain for structural studies. Protein Expr Purif 2022; 193:106058. [PMID: 35114376 DOI: 10.1016/j.pep.2022.106058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 12/21/2021] [Accepted: 01/28/2022] [Indexed: 10/19/2022]
Abstract
Neurotrophin signaling pathways are one of the major cascades in neuronal development and involved in many key processes including proliferation, differentiation, apoptosis, synaptic plasticity, axonal growth. In addition to the main classes of neurotrophin receptors, Trk and P75NTR, there are many auxiliary proteins, which can also bind neurotrophins and regulate the signaling pathways. The versatility of interactions between them could explain multiple and completely opposite biological outcomes such as cell survival or apoptosis. Membrane protein SorCS2, a vacuolar protein sorting 10 protein-domain receptor, interacts with P75NTR and controls the activity of Trk receptors. The abnormal functioning of SorCS2 is associated with neurodegenerative diseases, such as Alzheimer's and Huntington's disease. But the mechanism of SorCS2 activation and basis of the interaction with P75NTR has remained elusive. Herein, we describe two efficient approaches for the intracellular domain of the SorCS2 production employing bacterial and cell-free expression systems, as well as purification and refolding protocols. Finally, we characterized the purified protein by DLS and NMR and demonstrated that the protein sample is suitable for structural studies.
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Affiliation(s)
- L E Artemieva
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, Russia; Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - K S Mineev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, Russia
| | - A S Arseniev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, Russia
| | - S A Goncharuk
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, Russia.
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14
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Eggert S, Kins S, Endres K, Brigadski T. Brothers in arms: proBDNF/BDNF and sAPPα/Aβ-signaling and their common interplay with ADAM10, TrkB, p75NTR, sortilin, and sorLA in the progression of Alzheimer's disease. Biol Chem 2022; 403:43-71. [PMID: 34619027 DOI: 10.1515/hsz-2021-0330] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 09/16/2021] [Indexed: 12/22/2022]
Abstract
Brain-derived neurotrophic factor (BDNF) is an important modulator for a variety of functions in the central nervous system (CNS). A wealth of evidence, such as reduced mRNA and protein level in the brain, cerebrospinal fluid (CSF), and blood samples of Alzheimer's disease (AD) patients implicates a crucial role of BDNF in the progression of this disease. Especially, processing and subcellular localization of BDNF and its receptors TrkB and p75 are critical determinants for survival and death in neuronal cells. Similarly, the amyloid precursor protein (APP), a key player in Alzheimer's disease, and its cleavage fragments sAPPα and Aβ are known for their respective roles in neuroprotection and neuronal death. Common features of APP- and BDNF-signaling indicate a causal relationship in their mode of action. However, the interconnections of APP- and BDNF-signaling are not well understood. Therefore, we here discuss dimerization properties, localization, processing by α- and γ-secretase, relevance of the common interaction partners TrkB, p75, sorLA, and sortilin as well as shared signaling pathways of BDNF and sAPPα.
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Affiliation(s)
- Simone Eggert
- Department of Human Biology and Human Genetics, University of Kaiserslautern, Erwin-Schrödinger-Str. 13, D-67663 Kaiserslautern, Germany
| | - Stefan Kins
- Department of Human Biology and Human Genetics, University of Kaiserslautern, Erwin-Schrödinger-Str. 13, D-67663 Kaiserslautern, Germany
| | - Kristina Endres
- Department of Psychiatry and Psychotherapy, University Medical Center, Johannes Gutenberg-University Mainz, D-55131 Mainz, Germany
| | - Tanja Brigadski
- Department of Informatics and Microsystem Technology, University of Applied Sciences Kaiserslautern, D-66482 Zweibrücken, Germany
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15
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Sánchez ML, Coveñas R. The Neurotensinergic System: A Target for Cancer Treatment. Curr Med Chem 2021; 29:3231-3260. [PMID: 34711154 DOI: 10.2174/0929867328666211027124328] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 08/19/2021] [Accepted: 08/26/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND The scientific interest regarding the involvement of peptides in cancer has increased in the last years. In tumor cells the overexpression of peptides and their receptors is known and new therapeutic targets for the treatment of cancer have been suggested. The overexpression of the neurotensinergic system has been associated with poor prognosis, tumor size, higher tumor aggressiveness, increased relapse risk and worse sensitivity to chemotherapy agents. OBJECTIVE The aim of this review is to update the findings regarding the involvement of the neurotensinergic system in cancer to suggest anticancer therapeutic strategies targeting this system. The neurotensin (NT) precursor, NT and its receptors (NTR) and the involvement of the neurotensinergic system in lung, breast, prostate, gastric, colon, liver and pancreatic cancers, glioblastoma, neuroendocrine tumors and B-cell leukemia will be mentioned and discussed as well as the signaling pathways mediated by NT. Some research lines to be developed in the future will be suggested such as: molecules regulating the expression of the NT precursor, influence of the diet in the development of tumors, molecules and signaling pathways activated by NT and antitumor therapeutic strategies targeting the neurotensinergic system. CONCLUSION NT, via the NTR, exerts oncogenic (tumor cell proliferation, invasion, migration, angiogenesis) and antiapoptotic effects, whereas NTR antagonists inhibit these effects. NTR expression can be used as a diagnostic tool/therapeutic target and the administration of NTR antagonists as antitumor drugs could be a therapeutic strategy to treat tumors overexpressing NTR.
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Affiliation(s)
- Manuel Lisardo Sánchez
- University of Salamanca, Laboratory of Neuroanatomy of the Peptidergic Systems (Lab. 14), Institute of Neurosciences of Castilla y León (INCYL), Salamanca. Spain
| | - Rafael Coveñas
- University of Salamanca, Laboratory of Neuroanatomy of the Peptidergic Systems (Lab. 14), Institute of Neurosciences of Castilla y León (INCYL), Salamanca. Spain
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16
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Wang Y, Wang J, Zuo YC, Jiang J, Tu T, Yan XX, Liu F. Elevation of CSF Sortilin Following Subarachnoid Hemorrhage in Patients and Experimental Model Rats. Neuroscience 2021; 470:23-36. [PMID: 34273414 DOI: 10.1016/j.neuroscience.2021.07.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 07/04/2021] [Accepted: 07/06/2021] [Indexed: 10/20/2022]
Abstract
Subarachnoid hemorrhage (SAH) can cause acute neuronal injury and chronic neurocognitive deficits; biomarkers reflecting its associated neuronal injury are of potential prognostic value. Sortilin, a member of the vacuolar protein sorting 10p (Vps10p) family, is enriched in neurons and is likely involved in neurodegenerative diseases. Here, we explored sortilin in the cerebrospinal fluid (CSF) as a potential biomarker for early neuronal injury after SAH. Sortilin levels in the CSF of SAH patients (n = 11) and controls (n = 6) were analyzed by immunoblot. SAH rats surviving 3-72 h (h) were evaluated neurologically, with their brain and CSF samples examined histologically and biochemically. Sortilin protein ~100 kDa was detected in the CSF from SAH patients only, with its levels correlated to Hunt-Hess scale. Rats in the SAH groups showed poorer Garcia score and beam balancing capability than sham controls. Sortilin ~100 kDa was detectable in the CSF of the SAH, but not sham, animals. Levels of sortilin ~100 kDa and fragments ~40 kDa in cortical lysates were elevated in the SAH relative to control rats. Levels of cortical glial fibrillary acidic protein (GFAP) were also elevated in the SAH rats. In immunohistochemistry, the pattern of sortilin labeling in the brain was largely comparable between the SAH and control rats, whereas an increased astrocytic GFAP immunolabeling was evident in the former. Together, these results suggest that SAH can cause an early and remarkable rise of sortilin products in CSF, likely reflecting neuronal change. Sortilin could be further explored as a potential biomarker in some brain disorders.
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Affiliation(s)
- Yiping Wang
- Department of Neurosurgery, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong 519000, China
| | - Jikai Wang
- Department of Neurosurgery, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong 519000, China
| | - Yu-Chun Zuo
- Department of Neurosurgery, Xiangya Hospital Central South University, Changsha, Hunan 410008, China
| | - Juan Jiang
- Department of Anatomy and Neurobiology, Central South University Xiangya School of Medicine, Changsha, Hunan 410013, China
| | - Tian Tu
- Department of Anatomy and Neurobiology, Central South University Xiangya School of Medicine, Changsha, Hunan 410013, China
| | - Xiao-Xin Yan
- Department of Anatomy and Neurobiology, Central South University Xiangya School of Medicine, Changsha, Hunan 410013, China.
| | - Fei Liu
- Department of Neurosurgery, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong 519000, China.
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17
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Balogh RK, Németh E, Jones NC, Hoffmann SV, Jancsó A, Gyurcsik B. A study on the secondary structure of the metalloregulatory protein CueR: effect of pH, metal ions and DNA. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2021; 50:491-500. [PMID: 33907862 DOI: 10.1007/s00249-021-01539-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 01/13/2021] [Accepted: 04/14/2021] [Indexed: 11/30/2022]
Abstract
The response of CueR towards environmental changes in solution was investigated. CueR is a bacterial metal ion selective transcriptional metalloregulator protein, which controls the concentration of copper ions in the cell. Although several articles have been devoted to the discussion of the structural and functional features of this protein, CueR has not previously been extensively characterized in solution. Here, we studied the effect of change in pH, temperature, and the presence of specific or non-specific binding partners on the secondary structure of CueR with circular dichroism (CD) spectroscopy. A rather peculiar reversible pH-dependent secondary structure transformation was observed, elucidated and supplemented with pKa estimation by PROPKA and CpHMD simulations suggesting an important role of His(76) and His(94) in this process. CD experiments revealed that the presence of DNA prevents this structural switch, suggesting that DNA locks CueR in the α-helical-rich form. In contrast to the non-cognate metal ions HgII, CdII and ZnII, the presence of the cognate AgI ion affects the secondary structure of CueR, most probably by stabilizing the metal ion and DNA-binding domains of the protein.
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Affiliation(s)
- Ria K Balogh
- Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm tér 7, Szeged, 6720, Hungary
| | - Eszter Németh
- Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm tér 7, Szeged, 6720, Hungary.,Institute of Enzymology, Genome Stability Research Group, Research Centre for Natural Sciences, Magyar tudósok körútja 2, Budapest, 1117, Hungary
| | - Nykola C Jones
- ISA, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000, Aarhus C, Denmark
| | - Søren Vrønning Hoffmann
- ISA, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000, Aarhus C, Denmark
| | - Attila Jancsó
- Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm tér 7, Szeged, 6720, Hungary
| | - Béla Gyurcsik
- Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm tér 7, Szeged, 6720, Hungary.
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18
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Watanabe H, Yabe-Wada T, Onai N, Unno M. Detailed Structure of Mouse Interferon α2 and Its Interaction with Sortilin. J Biochem 2021; 170:265-273. [PMID: 33769476 DOI: 10.1093/jb/mvab038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 03/19/2021] [Indexed: 11/14/2022] Open
Abstract
Interferon α (IFNα) is a type I interferon, an essential cytokine employed by the immune system to fight viruses. Although a number of the structures of type I interferons have been reported, most of the known structures of IFNα are in complex with its receptors. There are only two examples of structures of free IFNα: one is a dimeric X-ray structure without side-chain information; and another is an NMR structure of human IFNα. Although we have shown that Sortilin is involved in the secretion of IFNα, the details of the molecular interaction and the secretion mechanism remain unclear. Recently, we solved the X-ray structure of mouse Sortilin, but the structure of mouse IFNα remained unknown. In the present study, we determined the crystal structure of mouse IFNα2 at 2.1 Å resolution and investigated its interaction with Sortilin. Docking simulations suggested that Arg22 of mouse IFNα2 is important for the interaction with mouse Sortilin. Mutation of Arg22 to alanine facilitated IFNα2 secretion, as determined by flow cytometry, highlighting the contribution of this residue to the interaction with Sortilin. These results suggest an important role for Arg22 in mouse IFNα for Sortilin-mediated IFNα trafficking.
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Affiliation(s)
- Honoka Watanabe
- Graduate School of Science and Engineering, Ibaraki University, Hitachi, Ibaraki 316-8511, Japan.,Frontier Research Center for Applied Atomic Sciences, Ibaraki University, Tokai Naka, Ibaraki 319-1106, Japan
| | - Toshiki Yabe-Wada
- Department of Immunology, Kanazawa Medical University, Kahoku Uchinada, Ishikawa 920-0293, Japan
| | - Nobuyuki Onai
- Department of Immunology, Kanazawa Medical University, Kahoku Uchinada, Ishikawa 920-0293, Japan
| | - Masaki Unno
- Graduate School of Science and Engineering, Ibaraki University, Hitachi, Ibaraki 316-8511, Japan.,Frontier Research Center for Applied Atomic Sciences, Ibaraki University, Tokai Naka, Ibaraki 319-1106, Japan
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19
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Kataria A, Patel AK, Kundu B. Distinct functional properties of secretory l-asparaginase Rv1538c involved in phagosomal survival of Mycobacterium tuberculosis. Biochimie 2021; 182:1-12. [PMID: 33412160 DOI: 10.1016/j.biochi.2020.12.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 12/15/2020] [Accepted: 12/28/2020] [Indexed: 11/17/2022]
Abstract
The emergence of drug-resistant Mycobacterium tuberculosis (Mtb) stains has escalated the need for developing more efficient drugs and therapeutic strategies against tuberculosis. Here we functionally annotate a secretory mycobacterial asparaginase Rv1538c (MtA) and describe its biochemical properties. MtA primarily existed as dimer along with a minor population of multimers. Circular dichroism and fluorescence spectroscopy demonstrated a compact structure in Tris HCl buffer at pH 8.0. Under these conditions it also displayed optimum activity. It retained ∼40% activity at pH 5.5, supporting its physiological relevance in acidic phagosomal environment. MtA contravened classical Michaelis-Menten kinetics and exhibited product inhibition profile, yielding a Kcat of 869.4 s-1 and an apparent Km of 8.36 mM. We report the presence of several antigenic epitopes and a C-terminal YXXXD/E motif in MtA, hinting towards its potential to interact or influence host immune system. This was supported by our observation of morphological changes in MtA-treated human B lymphoblasts. We propose that MtA is a dual purpose enzyme used by Mtb to survive inside its host by; 1) ammonia-mediated neutralization of the phagosomal acidic pH and 2) inducing stress to primary immune cells and compromising the host immune response. Overall, this study contributes to our understanding of the biological role of mycobacterial asparaginase opening avenues for developing effective TB therapeutics.
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Affiliation(s)
- Arti Kataria
- Kusuma School of Biological Sciences, IIT Delhi, Hauz Khas, New Delhi, India, 110016
| | - Ashok Kumar Patel
- Kusuma School of Biological Sciences, IIT Delhi, Hauz Khas, New Delhi, India, 110016
| | - Bishwajit Kundu
- Kusuma School of Biological Sciences, IIT Delhi, Hauz Khas, New Delhi, India, 110016.
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20
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Sparks RP, Arango AS, Jenkins JL, Guida WC, Tajkhorshid E, Sparks CE, Sparks JD, Fratti RA. An Allosteric Binding Site on Sortilin Regulates the Trafficking of VLDL, PCSK9, and LDLR in Hepatocytes. Biochemistry 2020; 59:4321-4335. [PMID: 33153264 DOI: 10.1021/acs.biochem.0c00741] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
ApoB lipoproteins (apo B-Lp) are produced in hepatocytes, and their secretion requires the cargo receptor sortilin. We examined the secretion of apo B-Lp-containing very low-density lipoprotein (VLDL), an LDL progenitor. Sortilin also regulates the trafficking of the subtilase PCSK9, which when secreted binds the LDL receptor (LDLR), resulting in its endocytosis and destruction at the lysosome. We show that the site 2 binding compound (cpd984) has multiple effects in hepatocytes, including (1) enhanced Apo-Lp secretion, (2) increased cellular PCSK9 retention, and (3) augmented levels of LDLR at the plasma membrane. We postulate that cpd984 enhances apo B-Lp secretion in part through binding the lipid phosphatidylinositol 3,4,5-trisphosphate (PIP3), which is present at higher levels on circulating VLDL form fed rats relative to after fasting. We attribute the enhanced VLDL secretion to its increased binding affinity for sortilin site 1 induced by cpd984 binding site 2. This hinders PCSK9 binding and secretion, which would subsequently prevent its binding to LDLR leading to its degradation. This suggests that site 2 is an allosteric regulator of site 1 binding. This effect is not limited to VLDL, as cpd984 augments binding of the neuropeptide neurotensin (NT) to sortilin site 1. Molecular dynamics simulations demonstrate that the C-terminus of NT (Ct-NT) stably binds site 1 through an electrostatic interaction. This was bolstered by the ability of Ct-NT to disrupt lower-affinity interactions between sortilin and the site 1 ligand PIP3. Together, these data show that binding cargo at sortilin site 1 is allosterically regulated through site 2 binding, with important ramifications for cellular lipid homeostasis involving proteins such as PCSK9 and LDLR.
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Affiliation(s)
- Robert P Sparks
- Department of Biochemistry, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Andres S Arango
- Center for Biophysics and Quantitative Biology, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Jermaine L Jenkins
- Structural Biology & Biophysics Facility, University of Rochester Medical Center, Rochester, New York 14642, United States
| | - Wayne C Guida
- Department of Chemistry, University of South Florida, Tampa, Florida 33620, United States
| | - Emad Tajkhorshid
- Department of Biochemistry, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States.,Center for Biophysics and Quantitative Biology, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States.,Beckman Institute for Advanced Science & Technology, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Charles E Sparks
- Department of Pathology & Laboratory Medicine, University of Rochester Medical Center, Rochester, New York 14642, United States
| | - Janet D Sparks
- Department of Pathology & Laboratory Medicine, University of Rochester Medical Center, Rochester, New York 14642, United States
| | - Rutilio A Fratti
- Department of Biochemistry, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States.,Center for Biophysics and Quantitative Biology, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States
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21
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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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22
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Chataigner LMP, Leloup N, Janssen BJC. Structural Perspectives on Extracellular Recognition and Conformational Changes of Several Type-I Transmembrane Receptors. Front Mol Biosci 2020; 7:129. [PMID: 32850948 PMCID: PMC7427315 DOI: 10.3389/fmolb.2020.00129] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 06/02/2020] [Indexed: 12/19/2022] Open
Abstract
Type-I transmembrane proteins represent a large group of 1,412 proteins in humans with a multitude of functions in cells and tissues. They are characterized by an extracellular, or luminal, N-terminus followed by a single transmembrane helix and a cytosolic C-terminus. The domain composition and structures of the extracellular and intercellular segments differ substantially amongst its members. Most of the type-I transmembrane proteins have roles in cell signaling processes, as ligands or receptors, and in cellular adhesion. The extracellular segment often determines specificity and can control signaling and adhesion. Here we focus on recent structural understanding on how the extracellular segments of several diverse type-I transmembrane proteins engage in interactions and can undergo conformational changes for their function. Interactions at the extracellular side by proteins on the same cell or between cells are enhanced by the transmembrane setting. Extracellular conformational domain rearrangement and structural changes within domains alter the properties of the proteins and are used to regulate signaling events. The combination of structural properties and interactions can support the formation of larger-order assemblies on the membrane surface that are important for cellular adhesion and intercellular signaling.
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Affiliation(s)
- Lucas M. P. Chataigner
- Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Nadia Leloup
- Structural Biology and Protein Biochemistry, Morphic Therapeutic, Waltham, MA, United States
| | - Bert J. C. Janssen
- Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Faculty of Science, Utrecht University, Utrecht, Netherlands
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23
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Vasanthakumar T, Rubinstein JL. Structure and Roles of V-type ATPases. Trends Biochem Sci 2020; 45:295-307. [PMID: 32001091 DOI: 10.1016/j.tibs.2019.12.007] [Citation(s) in RCA: 95] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 12/05/2019] [Accepted: 12/31/2019] [Indexed: 12/19/2022]
Abstract
V-ATPases are membrane-embedded protein complexes that function as ATP hydrolysis-driven proton pumps. V-ATPases are the primary source of organellar acidification in all eukaryotes, making them essential for many fundamental cellular processes. Enzymatic activity can be modulated by regulated and reversible disassembly of the complex, and several subunits of mammalian V-ATPase have multiple isoforms that are differentially localized. Although the biochemical properties of the different isoforms are currently unknown, mutations in specific subunit isoforms have been associated with various diseases, making V-ATPases potential drug targets. V-ATPase structure and activity have been best characterized in Saccharomyces cerevisiae, where recent structures have revealed details about the dynamics of the enzyme, the proton translocation pathway, and conformational changes associated with regulated disassembly and autoinhibition.
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Affiliation(s)
- Thamiya Vasanthakumar
- The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada; Department of Biochemistry, The University of Toronto, Toronto, ON M5S 1A8, Canada.
| | - John L Rubinstein
- The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada; Department of Biochemistry, The University of Toronto, Toronto, ON M5S 1A8, Canada; Department of Medical Biophysics, The University of Toronto, Toronto, ON M5G 1L7, Canada.
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24
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Boyken SE, Benhaim MA, Busch F, Jia M, Bick MJ, Choi H, Klima JC, Chen Z, Walkey C, Mileant A, Sahasrabuddhe A, Wei KY, Hodge EA, Byron S, Quijano-Rubio A, Sankaran B, King NP, Lippincott-Schwartz J, Wysocki VH, Lee KK, Baker D. De novo design of tunable, pH-driven conformational changes. Science 2019; 364:658-664. [PMID: 31097662 DOI: 10.1126/science.aav7897] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 04/24/2019] [Indexed: 01/03/2023]
Abstract
The ability of naturally occurring proteins to change conformation in response to environmental changes is critical to biological function. Although there have been advances in the de novo design of stable proteins with a single, deep free-energy minimum, the design of conformational switches remains challenging. We present a general strategy to design pH-responsive protein conformational changes by precisely preorganizing histidine residues in buried hydrogen-bond networks. We design homotrimers and heterodimers that are stable above pH 6.5 but undergo cooperative, large-scale conformational changes when the pH is lowered and electrostatic and steric repulsion builds up as the network histidine residues become protonated. The transition pH and cooperativity can be controlled through the number of histidine-containing networks and the strength of the surrounding hydrophobic interactions. Upon disassembly, the designed proteins disrupt lipid membranes both in vitro and after being endocytosed in mammalian cells. Our results demonstrate that environmentally triggered conformational changes can now be programmed by de novo protein design.
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Affiliation(s)
- Scott E Boyken
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA.,Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | - Mark A Benhaim
- Department of Medicinal Chemistry, University of Washington, Seattle, WA 98195, USA
| | - Florian Busch
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Mengxuan Jia
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Matthew J Bick
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA.,Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | - Heejun Choi
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA
| | - Jason C Klima
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA.,Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | - Zibo Chen
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA.,Institute for Protein Design, University of Washington, Seattle, WA 98195, USA.,Graduate Program in Biological Physics, Structure, and Design, University of Washington, Seattle, WA, USA
| | - Carl Walkey
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA.,Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | - Alexander Mileant
- Department of Medicinal Chemistry, University of Washington, Seattle, WA 98195, USA.,Graduate Program in Biological Physics, Structure, and Design, University of Washington, Seattle, WA, USA
| | - Aniruddha Sahasrabuddhe
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Kathy Y Wei
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA.,Institute for Protein Design, University of Washington, Seattle, WA 98195, USA.,Department of Bioengineering, University of California, Berkeley, CA 94720, USA
| | - Edgar A Hodge
- Department of Medicinal Chemistry, University of Washington, Seattle, WA 98195, USA
| | - Sarah Byron
- Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | - Alfredo Quijano-Rubio
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA.,Institute for Protein Design, University of Washington, Seattle, WA 98195, USA.,Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Banumathi Sankaran
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720
| | - Neil P King
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA.,Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | | | - Vicki H Wysocki
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Kelly K Lee
- Department of Medicinal Chemistry, University of Washington, Seattle, WA 98195, USA.,Graduate Program in Biological Physics, Structure, and Design, University of Washington, Seattle, WA, USA
| | - David Baker
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA. .,Institute for Protein Design, University of Washington, Seattle, WA 98195, USA.,Howard Hughes Medical Institute, University of Washington, Seattle, WA 98195, USA
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25
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Chaves G, Stanley J, Pourmand N. Mutant Huntingtin Affects Diabetes and Alzheimer's Markers in Human and Cell Models of Huntington's Disease. Cells 2019; 8:E962. [PMID: 31450785 PMCID: PMC6769852 DOI: 10.3390/cells8090962] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 08/14/2019] [Accepted: 08/21/2019] [Indexed: 02/07/2023] Open
Abstract
A higher incidence of diabetes was observed among family members of individuals affected by Huntington's Disease with no follow-up studies investigating the genetic nature of the observation. Using a genome-wide association study (GWAS), RNA sequencing (RNA-Seq) analysis and western blotting of Rattus norvegicus and human, we were able to identify that the gene family of sortilin receptors was affected in Huntington's Disease patients. We observed that less than 5% of SNPs were of statistical significance and that sortilins and HLA/MHC gene expression or SNPs were associated with mutant huntingtin (mHTT). These results suggest that ST14A cells derived from R. norvegicus are a reliable model of HD, since sortilins were identified through analysis of the transcriptome in these cells. These findings help highlight the genes involved in mechanisms targeted by diabetes drugs, such as glucose transporters as well as proteins controlling insulin release related to mHTT. To the best of our knowledge, this is the first GWAS using RNA-Seq data from both ST14A rat HD cell model and human Huntington's Disease.
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Affiliation(s)
- Gepoliano Chaves
- Department of Biomolecular Engineering, University of California, Santa Cruz, CA 95064, USA
| | - John Stanley
- Department of Biomolecular Engineering, University of California, Santa Cruz, CA 95064, USA
| | - Nader Pourmand
- Department of Biomolecular Engineering, University of California, Santa Cruz, CA 95064, USA.
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26
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Abstract
PURPOSE OF REVIEW Sortilin, encoded SORT1 gene at chromosome 1p13.3, is a multiligand receptor that traffics protein from the Golgi to the endosomes, secretory vesicles, and the cell surface. Genome-wide association studies (GWAS) revealed an association between sortilin and reduced plasma LDL-cholesterol (LDL-C) as well as reduced coronary artery disease (CAD). This review explores the various lipid metabolism pathways that are affected by alterations in sortilin expression. RECENT FINDINGS The effects of increased hepatic sortilin on plasma LDL-C levels are mediated by increased clearance of LDL-C and decreased very LDL (VLDL) secretion because of increased autophagy-mediated lysosomal degradation of apolipoproteinB100. Sort1 knockout models have shown opposite VLDL secretion phenotypes as well as whole body lipid metabolism in response to diet challenges, leading to confusion about the true role of sortilin in the liver and other tissues. SUMMARY The regulation of VLDL secretion by hepatic sortilin is complex and remains incompletely understood. Further investigation to determine the specific conditions under which both hepatic sortilin and total body sortilin cause changes in lipid metabolism pathways is needed.
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Affiliation(s)
- Donna M Conlon
- Division of Translational Medicine and Human Genetics, Department of Medicine, University of Pennsylvania, Philadelphia, USA
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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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Mazella J, Borsotto M, Heurteaux C. The Involvement of Sortilin/NTSR3 in Depression as the Progenitor of Spadin and Its Role in the Membrane Expression of TREK-1. Front Pharmacol 2019; 9:1541. [PMID: 30670975 PMCID: PMC6331531 DOI: 10.3389/fphar.2018.01541] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 12/17/2018] [Indexed: 12/31/2022] Open
Abstract
The molecular identification of sortilin, also called neurotensin receptor-3, from three different biochemical approaches already predicted the involvement of the protein in numerous biological and cellular functions. The first important observation was that sortilin is synthesized as a precursor that is converted to a mature protein after cleavage by the protein convertase furin in late Golgi compartments. This maturation leads to the formation of a 44 amino acid peptide, the propeptide (PE). The release of this peptide when matured sortilin reached the plasma membrane remained to be demonstrated. Sortilin has been also shown to be shedded by matrix metalloproteases releasing a large extracellular fragment identified as soluble sortilin. Therefore, sortilin has been shown to interact with several proteins and receptors confirming its role in the sorting of cellular components to the plasma membrane and/or to the lysosomal pathway. Interestingly, sortilin physically interacts with the two pore domain potassium channel TREK-1 and the PE as well as its synthetic analog spadin is able to block the activation of TREK-1 highlighting their role in the depression pathology. The present review describes the advance of research that led to these results and how both the soluble form of sortilin and the sortilin-derived PE have been detected in human serum and whose levels are affected in patients with major depressive disorder (MDD). The use of spadin as an antidepressant and the further role of soluble sortilin and of sortilin-derived PE as potential biomarkers during depression statement and/or remission of the pathology are considered and discussed in this review.
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Affiliation(s)
- Jean Mazella
- CNRS, UMR 7275, Institut de Pharmacologie Moléculaire et Cellulaire, Université Côte d'Azur, Valbonne, France
| | - Marc Borsotto
- CNRS, UMR 7275, Institut de Pharmacologie Moléculaire et Cellulaire, Université Côte d'Azur, Valbonne, France
| | - Catherine Heurteaux
- CNRS, UMR 7275, Institut de Pharmacologie Moléculaire et Cellulaire, Université Côte d'Azur, Valbonne, France
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29
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Kim CL, Jung MY, Kim YS, Jang JW, Lee GM. Improving the production of recombinant human bone morphogenetic protein-4 in Chinese hamster ovary cell cultures by inhibition of undesirable endocytosis. Biotechnol Bioeng 2018; 115:2565-2575. [PMID: 30011067 DOI: 10.1002/bit.26798] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 06/30/2018] [Accepted: 07/11/2018] [Indexed: 12/17/2023]
Abstract
Endocytic regulation serves a critical role in modulating the extracellular level of signaling molecules, such as bone morphogenetic proteins (BMPs). Unfortunately, endocytosis may result in poor yields of recombinant human BMP-4 (rhBMP-4) from Chinese hamster ovary (CHO) cell cultures. When rhBMP-4 was incubated with CHO cells, rhBMP-4 was actively internalized into cells. Cell surface bound heparan sulfate proteoglycans (HSPGs) served as the major receptors for rhBMP-4 internalization. Removal of cell surface heparan sulfate (HS) by heparinases or reduction of HSPG synthesis by knockdown of xylosyltransferase2 (xylt2) in CHO cells decreased internalization of rhBMP-4. In addition, treatment with endocytosis inhibitors (chlorpromazine, genistein, and dynasore) identified a clathrin- and dynamin-dependent endocytic pathway as the major route for rhBMP-4 internalization. To enhance product yield by minimizing rhBMP-4 internalization in recombinant CHO (rCHO) cell cultures, we have tested various strategies to reduce HSPG synthesis (knockdown of xylt2 and sodium chlorate treatment) or inhibit the binding of rhBMP-4 to cell-surface-bound HSPGs (supplementation with heparin or dextran sulfate [DS]). Among these approaches, DS, which is a linear anionic sulfated polysaccharide with similarity to HS chains, was the most effective in enhancing rhBMP-4 production in rCHO cell cultures. Compared with the control cultures, DS addition to the culture medium (1.0 g/L) resulted in 1.4-fold and 2.3-fold increases in maximum rhBMP-4 concentration in batch and fed-batch cultures, respectively. Taken together, the addition of DS, an effective competitor of HSPGs, improved rhBMP-4 production in rCHO cell cultures through blockage of rhBMP-4 internalization.
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Affiliation(s)
- Che Lin Kim
- Department of Biological Sciences, KAIST, Daejeon, Republic of Korea
| | - Mi Yeong Jung
- Institute of Biomaterial and Medical Engineering, Cellumed, Seoul, Republic of Korea
| | - Young Sik Kim
- Institute of Biomaterial and Medical Engineering, Cellumed, Seoul, Republic of Korea
| | - Ju Woong Jang
- Institute of Biomaterial and Medical Engineering, Cellumed, Seoul, Republic of Korea
| | - Gyun Min Lee
- Department of Biological Sciences, KAIST, Daejeon, Republic of Korea
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30
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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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31
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Yabe‐Wada T, Matsuba S, Unno M, Onai N. Crystal structure of the ligand‐free form of the Vps10 ectodomain of dimerized Sortilin at acidic
pH. FEBS Lett 2018; 592:2647-2657. [DOI: 10.1002/1873-3468.13181] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 06/18/2018] [Accepted: 06/29/2018] [Indexed: 12/12/2022]
Affiliation(s)
| | - Shintaro Matsuba
- Department of Immunology Kanazawa Medical University Uchinada Japan
| | - Masaki Unno
- Graduate School of Science and Engineering Ibaraki University Japan
| | - Nobuyuki Onai
- Department of Immunology Kanazawa Medical University Uchinada Japan
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32
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Blechingberg J, Poulsen ASA, Kjølby M, Monti G, Allen M, Ivarsen AK, Lincoln SJ, Thotakura G, Vægter CB, Ertekin-Taner N, Nykjær A, Andersen OM. An alternative transcript of the Alzheimer's disease risk gene SORL1 encodes a truncated receptor. Neurobiol Aging 2018; 71:266.e11-266.e24. [PMID: 30078640 DOI: 10.1016/j.neurobiolaging.2018.06.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 06/03/2018] [Accepted: 06/18/2018] [Indexed: 10/28/2022]
Abstract
SORL1 encodes a 250-kDa protein named sorLA, a functional sorting receptor for the amyloid precursor protein (APP). Several single nucleotide polymorphisms of the gene SORL1, encoding sorLA, are genetically associated with Alzheimer's disease (AD). In the existing literature, SORL1 is insufficiently described at the transcriptional level, and there is very limited amount of functional data defining different transcripts. We have characterized a SORL1 transcript containing a novel exon 30B. The transcript is expressed in most brain regions with highest expression in the temporal lobe and hippocampus. Exon 30B is spliced to exon 31, leading to a mature transcript that encodes an 829 amino acid sorLA receptor. This receptor variant lacks the binding site for APP and is unlikely to function in APP sorting. This transcript is expressed in equal amounts in the cerebellum from AD and non-AD individuals. Our data describe a transcript that encodes a truncated sorLA receptor, suggesting novel neuronal functions for sorLA and that alternative transcription provides a mechanism for SORL1 activity regulation.
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Affiliation(s)
- Jenny Blechingberg
- Danish Research Institute of Translational Neuroscience (DANDRITE) Nordic-EMBL Partnership, Aarhus, Denmark
| | | | - Mads Kjølby
- Danish Research Institute of Translational Neuroscience (DANDRITE) Nordic-EMBL Partnership, Aarhus, Denmark; Danish Diabetes Academy, Novo Nordisk Foundation, Aarhus University, Aarhus, Denmark
| | - Giulia Monti
- Danish Research Institute of Translational Neuroscience (DANDRITE) Nordic-EMBL Partnership, Aarhus, Denmark
| | - Mariet Allen
- Department of Neuroscience, Mayo Clinic, FL, USA
| | - Anne Kathrine Ivarsen
- Danish Research Institute of Translational Neuroscience (DANDRITE) Nordic-EMBL Partnership, Aarhus, Denmark
| | | | | | - Christian B Vægter
- Danish Research Institute of Translational Neuroscience (DANDRITE) Nordic-EMBL Partnership, Aarhus, Denmark
| | | | - Anders Nykjær
- Danish Research Institute of Translational Neuroscience (DANDRITE) Nordic-EMBL Partnership, Aarhus, Denmark; The Lundbeck Foundation Research Center MIND, Aarhus, Denmark; The Danish Research Foundation Center PROMEMO, Department of Biomedicine, Aarhus, Denmark; Department of Neurosurgery, Aarhus University Hospital, Aarhus, Denmark
| | - Olav M Andersen
- Danish Research Institute of Translational Neuroscience (DANDRITE) Nordic-EMBL Partnership, Aarhus, Denmark.
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