1
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Schilling KM, Jorwal P, Ubilla-Rodriguez NC, Assafa TE, Gatdula JRP, Vultaggio JS, Harris DA, Millhauser GL. N-glycosylation is a potent regulator of prion protein neurotoxicity. J Biol Chem 2023; 299:105101. [PMID: 37507020 PMCID: PMC10469999 DOI: 10.1016/j.jbc.2023.105101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 07/05/2023] [Accepted: 07/25/2023] [Indexed: 07/30/2023] Open
Abstract
The C-terminal domain of the cellular prion protein (PrPC) contains two N-linked glycosylation sites, the occupancy of which impacts disease pathology. In this study, we demonstrate that glycans at these sites are required to maintain an intramolecular interaction with the N-terminal domain, mediated through a previously identified copper-histidine tether, which suppresses the neurotoxic activity of PrPC. NMR and electron paramagnetic resonance spectroscopy demonstrate that the glycans refine the structure of the protein's interdomain interaction. Using whole-cell patch-clamp electrophysiology, we further show that cultured cells expressing PrP molecules with mutated glycosylation sites display large, spontaneous inward currents, a correlate of PrP-induced neurotoxicity. Our findings establish a structural basis for the role of N-linked glycans in maintaining a nontoxic, physiological fold of PrPC.
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Affiliation(s)
- Kevin M Schilling
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California, USA
| | - Pooja Jorwal
- Department of Biochemistry, Chobanian & Avedisian School of Medicine, Boston University, Boston, Massachusetts, USA
| | | | - Tufa E Assafa
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California, USA
| | - Jean R P Gatdula
- Department of Biochemistry, Chobanian & Avedisian School of Medicine, Boston University, Boston, Massachusetts, USA
| | - Janelle S Vultaggio
- Department of Biochemistry, Chobanian & Avedisian School of Medicine, Boston University, Boston, Massachusetts, USA
| | - David A Harris
- Department of Biochemistry, Chobanian & Avedisian School of Medicine, Boston University, Boston, Massachusetts, USA.
| | - Glenn L Millhauser
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California, USA.
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2
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Alves Conceição C, Assis de Lemos G, Barros CA, Vieira TCRG. What is the role of lipids in prion conversion and disease? Front Mol Neurosci 2023; 15:1032541. [PMID: 36704327 PMCID: PMC9871914 DOI: 10.3389/fnmol.2022.1032541] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 12/19/2022] [Indexed: 01/12/2023] Open
Abstract
The molecular cause of transmissible spongiform encephalopathies (TSEs) involves the conversion of the cellular prion protein (PrPC) into its pathogenic form, called prion scrapie (PrPSc), which is prone to the formation of amorphous and amyloid aggregates found in TSE patients. Although the mechanisms of conversion of PrPC into PrPSc are not entirely understood, two key points are currently accepted: (i) PrPSc acts as a seed for the recruitment of native PrPC, inducing the latter's conversion to PrPSc; and (ii) other biomolecules, such as DNA, RNA, or lipids, can act as cofactors, mediating the conversion from PrPC to PrPSc. Interestingly, PrPC is anchored by a glycosylphosphatidylinositol molecule in the outer cell membrane. Therefore, interactions with lipid membranes or alterations in the membranes themselves have been widely investigated as possible factors for conversion. Alone or in combination with RNA molecules, lipids can induce the formation of PrP in vitro-produced aggregates capable of infecting animal models. Here, we discuss the role of lipids in prion conversion and infectivity, highlighting the structural and cytotoxic aspects of lipid-prion interactions. Strikingly, disorders like Alzheimer's and Parkinson's disease also seem to be caused by changes in protein structure and share pathogenic mechanisms with TSEs. Thus, we posit that comprehending the process of PrP conversion is relevant to understanding critical events involved in a variety of neurodegenerative disorders and will contribute to developing future therapeutic strategies for these devastating conditions.
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Affiliation(s)
- Cyntia Alves Conceição
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil,National Institute of Science and Technology for Structural Biology and Bioimaging, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gabriela Assis de Lemos
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil,National Institute of Science and Technology for Structural Biology and Bioimaging, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Caroline Augusto Barros
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil,National Institute of Science and Technology for Structural Biology and Bioimaging, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Tuane C. R. G. Vieira
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil,National Institute of Science and Technology for Structural Biology and Bioimaging, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil,*Correspondence: Tuane C. R. G. Vieira, ✉
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3
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Hanna CC, Kriegesmann J, Dowman LJ, Becker CFW, Payne RJ. Chemische Synthese und Semisynthese von lipidierten Proteinen. ANGEWANDTE CHEMIE (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 134:e202111266. [PMID: 38504765 PMCID: PMC10947004 DOI: 10.1002/ange.202111266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Indexed: 11/11/2022]
Abstract
AbstractLipidierung ist eine ubiquitäre Modifikation von Peptiden und Proteinen, die entweder co‐ oder posttranslational auftreten kann. Für die Vielzahl von Lipidklassen wurde gezeigt, dass diese viele entscheidende biologische Aktivitäten, z. B. die Regulierung der Signalweiterleitung, Zell‐Zell‐Adhäsion sowie die Anlagerung von Proteinen an Lipid‐Rafts und Phospholipidmembranen, beeinflussen. Während die Natur Enzyme nutzt, um Lipidmodifikationen in Proteine einzubringen, ist ihre Nutzung für die chemoenzymatische Herstellung von lipidierten Proteinen häufig ineffizient. Eine Alternative ist die Kombination moderner synthetischer und semisynthetischer Techniken, um lipidierte Proteine in reiner und homogen modifizierter Form zu erhalten. Dieser Aufsatz erörtert Fortschritte in der Entwicklung der Lipidierungs‐ und Ligationschemie und deren Anwendung in der Synthese und Semisynthese homogen lipidierter Proteine, die es ermöglichen, den Einfluss dieser Modifikationen auf die Proteinstruktur und ‐funktion zu untersuchen.
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Affiliation(s)
- Cameron C. Hanna
- School of ChemistryThe University of SydneySydneyNSW2006Australien
| | - Julia Kriegesmann
- Institut für Biologische ChemieFakultät für ChemieUniversität WienWienÖsterreich
| | - Luke J. Dowman
- School of ChemistryThe University of SydneySydneyNSW2006Australien
- Australian Research Council Centre of Excellence for Innovations in Peptide and Protein ScienceThe University of SydneySydneyNSW2006Australien
| | | | - Richard J. Payne
- School of ChemistryThe University of SydneySydneyNSW2006Australien
- Australian Research Council Centre of Excellence for Innovations in Peptide and Protein ScienceThe University of SydneySydneyNSW2006Australien
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4
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Hanna C, Kriegesmann J, Dowman L, Becker C, Payne RJ. Chemical Synthesis and Semisynthesis of Lipidated Proteins. Angew Chem Int Ed Engl 2021; 61:e202111266. [PMID: 34611966 PMCID: PMC9303669 DOI: 10.1002/anie.202111266] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Indexed: 11/24/2022]
Abstract
Lipidation is a ubiquitous modification of peptides and proteins that can occur either co‐ or post‐translationally. An array of different lipid classes can adorn proteins and has been shown to influence a number of crucial biological activities, including the regulation of signaling, cell–cell adhesion events, and the anchoring of proteins to lipid rafts and phospholipid membranes. Whereas nature employs a range of enzymes to install lipid modifications onto proteins, the use of these for the chemoenzymatic generation of lipidated proteins is often inefficient or impractical. An alternative is to harness the power of modern synthetic and semisynthetic technologies to access lipid‐modified proteins in a pure and homogeneously modified form. This Review aims to highlight significant advances in the development of lipidation and ligation chemistry and their implementation in the synthesis and semisynthesis of homogeneous lipidated proteins that have enabled the influence of these modifications on protein structure and function to be uncovered.
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Affiliation(s)
- Cameron Hanna
- The University of Sydney, Chemistry, 2006, Sydney, AUSTRALIA
| | - Julia Kriegesmann
- University of Vienna: Universitat Wien, Institute of Biological Chemistry, Vienna, AUSTRIA
| | - Luke Dowman
- The University of Sydney, School of Chemistry, 2006, Sydney, AUSTRALIA
| | - Christian Becker
- University of Vienna Faculty of Chemistry: Universitat Wien Fakultat fur Chemie, Institute of Biological Chemistry, Vienna, AUSTRIA
| | - Richard James Payne
- The University of Sydney, School of Chemistry, Eastern Avenue, 2006, Sydney, AUSTRALIA
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5
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Hackl S, Ng XW, Lu D, Wohland T, Becker CFW. Cytoskeleton-dependent clustering of membrane-bound prion protein on the cell surface. J Biol Chem 2021; 296:100359. [PMID: 33539927 PMCID: PMC7988330 DOI: 10.1016/j.jbc.2021.100359] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 01/26/2021] [Accepted: 01/28/2021] [Indexed: 12/23/2022] Open
Abstract
Prion diseases are a group of neurodegenerative disorders that infect animals and humans with proteinaceous particles called prions. Prions consist of scrapie prion protein (PrPSc), a misfolded version of the cellular prion protein (PrPC). During disease progression, PrPSc replicates by interacting with PrPC and inducing its conversion to PrPSc. Attachment of PrPC to cellular membranes via a glycosylphosphatidylinositol (GPI) anchor is critical for the conversion of PrPC into PrPSc. However, the mechanisms governing PrPC conversion and replication on the membrane remain largely unclear. Here, a site-selectively modified PrP variant equipped with a fluorescent GPI anchor mimic (PrP-GPI) was employed to directly observe PrP at the cellular membrane in neuronal SH-SY5Y cells. PrP-GPI exhibits a cholesterol-dependent membrane accumulation and a cytoskeleton-dependent mobility. More specifically, inhibition of actin polymerization reduced the diffusion of PrP-GPI indicating protein clustering, which resembles the initial step of PrP aggregation and conversion into its pathogenic isoform. An intact actin cytoskeleton might therefore prevent conversion of PrPC into PrPSc and offer new therapeutic angles.
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Affiliation(s)
- Stefanie Hackl
- Institute of Biological Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Xue Wen Ng
- Departments of Biological Sciences and Chemistry and Centre for Bioimaging Sciences (CBIS), National University of Singapore (NUS), Singapore
| | - Danqin Lu
- Departments of Biological Sciences and Chemistry and Centre for Bioimaging Sciences (CBIS), National University of Singapore (NUS), Singapore; School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China
| | - Thorsten Wohland
- Departments of Biological Sciences and Chemistry and Centre for Bioimaging Sciences (CBIS), National University of Singapore (NUS), Singapore
| | - Christian F W Becker
- Institute of Biological Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria.
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6
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Abstract
Protein semisynthesis-defined herein as the assembly of a protein from a combination of synthetic and recombinant fragments-is a burgeoning field of chemical biology that has impacted many areas in the life sciences. In this review, we provide a comprehensive survey of this area. We begin by discussing the various chemical and enzymatic methods now available for the manufacture of custom proteins containing noncoded elements. This section begins with a discussion of methods that are more chemical in origin and ends with those that employ biocatalysts. We also illustrate the commonalities that exist between these seemingly disparate methods and show how this is allowing for the development of integrated chemoenzymatic methods. This methodology discussion provides the technical foundation for the second part of the review where we cover the great many biological problems that have now been addressed using these tools. Finally, we end the piece with a short discussion on the frontiers of the field and the opportunities available for the future.
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Affiliation(s)
| | - Tom W. Muir
- Department of Chemistry, Princeton University, Frick Laboratory, Princeton, New Jersey 08544, United States
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7
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Agarwal A, Das D, Banerjee T, Mukhopadhyay S. Energy migration captures membrane-induced oligomerization of the prion protein. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1868:140324. [DOI: 10.1016/j.bbapap.2019.140324] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 10/23/2019] [Accepted: 10/26/2019] [Indexed: 12/22/2022]
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8
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Hackl S, Becker CFW. Prion protein-Semisynthetic prion protein (PrP) variants with posttranslational modifications. J Pept Sci 2019; 25:e3216. [PMID: 31713950 PMCID: PMC6899880 DOI: 10.1002/psc.3216] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 08/23/2019] [Accepted: 08/23/2019] [Indexed: 12/16/2022]
Abstract
Deciphering the pathophysiologic events in prion diseases is challenging, and the role of posttranslational modifications (PTMs) such as glypidation and glycosylation remains elusive due to the lack of homogeneous protein preparations. So far, experimental studies have been limited in directly analyzing the earliest events of the conformational change of cellular prion protein (PrPC ) into scrapie prion protein (PrPSc ) that further propagates PrPC misfolding and aggregation at the cellular membrane, the initial site of prion infection, and PrP misfolding, by a lack of suitably modified PrP variants. PTMs of PrP, especially attachment of the glycosylphosphatidylinositol (GPI) anchor, have been shown to be crucially involved in the PrPSc formation. To this end, semisynthesis offers a unique possibility to understand PrP behavior invitro and invivo as it provides access to defined site-selectively modified PrP variants. This approach relies on the production and chemoselective linkage of peptide segments, amenable to chemical modifications, with recombinantly produced protein segments. In this article, advances in understanding PrP conversion using semisynthesis as a tool to obtain homogeneous posttranslationally modified PrP will be discussed.
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Affiliation(s)
- Stefanie Hackl
- University of Vienna, Faculty of Chemistry, Institute of Biological Chemistry, Vienna, Austria
| | - Christian F W Becker
- University of Vienna, Faculty of Chemistry, Institute of Biological Chemistry, Vienna, Austria
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9
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Araman C, 't Hart BA. Neurodegeneration meets immunology - A chemical biology perspective. Bioorg Med Chem 2019; 27:1911-1924. [PMID: 30910473 DOI: 10.1016/j.bmc.2019.03.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/14/2019] [Accepted: 03/19/2019] [Indexed: 11/16/2022]
Affiliation(s)
- C Araman
- Leiden Institute of Chemistry and the Institute for Chemical Immunology, Leiden University, Leiden, The Netherlands.
| | - B A 't Hart
- University of Groningen, Department of Biomedical Sciences of Cells and Systems, University Medical Centre, Groningen, The Netherlands; Department Anatomy and Neuroscience, Free University Medical Center (VUmc), Amsterdam, The Netherlands.
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10
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Le NTT, Wu B, Harris DA. Prion neurotoxicity. Brain Pathol 2019; 29:263-277. [PMID: 30588688 DOI: 10.1111/bpa.12694] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 11/28/2018] [Indexed: 01/04/2023] Open
Abstract
Although the mechanisms underlying prion propagation and infectivity are now well established, the processes accounting for prion toxicity and pathogenesis have remained mysterious. These processes are of enormous clinical relevance as they hold the key to identification of new molecular targets for therapeutic intervention. In this review, we will discuss two broad areas of investigation relevant to understanding prion neurotoxicity. The first is the use of in vitro experimental systems that model key events in prion pathogenesis. In this context, we will describe a hippocampal neuronal culture system we developed that reproduces the earliest pathological alterations in synaptic morphology and function in response to PrPSc . This system has allowed us to define a core synaptotoxic signaling pathway involving the activation of NMDA and AMPA receptors, stimulation of p38 MAPK phosphorylation and collapse of the actin cytoskeleton in dendritic spines. The second area concerns a striking and unexpected phenomenon in which certain structural manipulations of the PrPC molecule itself, including introduction of N-terminal deletion mutations or binding of antibodies to C-terminal epitopes, unleash powerful toxic effects in cultured cells and transgenic mice. We will describe our studies of this phenomenon, which led to the recognition that it is related to the induction of large, abnormal ionic currents by the structurally altered PrP molecules. Our results suggest a model in which the flexible N-terminal domain of PrPC serves as a toxic effector which is regulated by intramolecular interactions with the globular C-terminal domain. Taken together, these two areas of study have provided important clues to underlying cellular and molecular mechanisms of prion neurotoxicity. Nevertheless, much remains to be done on this next frontier of prion science.
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Affiliation(s)
- Nhat T T Le
- Department of Biochemistry, Boston University School of Medicine, Boston, MA
| | - Bei Wu
- Department of Biochemistry, Boston University School of Medicine, Boston, MA
| | - David A Harris
- Department of Biochemistry, Boston University School of Medicine, Boston, MA
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11
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Teruya K, Nishizawa K, Oguma A, Sakasegawa Y, Kitamoto T, Doh-Ura K. Intermolecular crosslinking of abnormal prion protein is efficiently induced by a primuline-sensitized photoreaction. Biochim Biophys Acta Gen Subj 2018; 1863:384-394. [PMID: 30447252 DOI: 10.1016/j.bbagen.2018.11.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 10/26/2018] [Accepted: 11/13/2018] [Indexed: 11/16/2022]
Abstract
In prion diseases, infectious pathogenic particles that are composed of abnormal prion proteins (PrPSc) accumulate in the brain. PrPSc is biochemically characterized by its protease-resistance core (PrPres), but its structural features have not been fully elucidated. Here, we report that primuline, a fluorescent dye with photosensitization activity, dramatically enhances UV-irradiation-induced SDS-resistant PrPSc/res oligomer formation that can be detected by immunoblot analysis of prion-infected materials. This oligomer formation occurs specifically with PrPSc/res but not with normal prion protein, and it was demonstrated using purified PrPSc/res as well as unpurified materials. The oligomer formation proceeded in both primuline-dose- and UV irradiation time-dependent manners. Treatment with urea or formic acid did not break oligomers into monomers. Neither did the presence of aromatic amino acids modify oligomer formation. Analysis with a panel of anti-prion protein antibodies showed that the antibodies against the N-terminal region of PrPres were less reactive in the dimer than the monomer. These findings suggest that the primuline-sensitized photoreaction enhances intermolecular crosslinking of PrPSc/res molecules at a hydrophobic area of the N-terminal region of PrPres. In the screening of other compounds, photoreactive compounds such as luciferin exhibited a similar but lower activity with respect to oligomer formation than primuline. The enhanced photoreaction with these compounds will be useful for evaluating the structural features of PrPSc/res, especially the interactions between PrPSc/res molecules.
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Affiliation(s)
- Kenta Teruya
- Department of Neurochemistry, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Keiko Nishizawa
- Department of Neurochemistry, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Ayumi Oguma
- Department of Neurochemistry, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yuji Sakasegawa
- Department of Neurochemistry, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Tetsuyuki Kitamoto
- Department of Neurological Science, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Katsumi Doh-Ura
- Department of Neurochemistry, Tohoku University Graduate School of Medicine, Sendai, Japan.
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12
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Chu N, Salguero AL, Liu AZ, Chen Z, Dempsey DR, Ficarro SB, Alexander WM, Marto JA, Li Y, Amzel LM, Gabelli SB, Cole PA. Akt Kinase Activation Mechanisms Revealed Using Protein Semisynthesis. Cell 2018; 174:897-907.e14. [PMID: 30078705 DOI: 10.1016/j.cell.2018.07.003] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 05/15/2018] [Accepted: 07/03/2018] [Indexed: 11/30/2022]
Abstract
Akt is a critical protein kinase that drives cancer proliferation, modulates metabolism, and is activated by C-terminal phosphorylation. The current structural model for Akt activation by C-terminal phosphorylation has centered on intramolecular interactions between the C-terminal tail and the N lobe of the kinase domain. Here, we employ expressed protein ligation to produce site-specifically phosphorylated forms of purified Akt1 that are well suited for mechanistic analysis. Using biochemical, crystallographic, and cellular approaches, we determine that pSer473-Akt activation is driven by an intramolecular interaction between the C-tail and the pleckstrin homology (PH)-kinase domain linker that relieves PH domain-mediated Akt1 autoinhibition. Moreover, dual phosphorylation at Ser477/Thr479 activates Akt1 through a different allosteric mechanism via an apparent activation loop interaction that reduces autoinhibition by the PH domain and weakens PIP3 affinity. These results provide a new framework for understanding how Akt is controlled in cell signaling and suggest distinct functions for differentially modified Akt forms.
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Affiliation(s)
- Nam Chu
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Antonieta L Salguero
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Albert Z Liu
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Zan Chen
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Daniel R Dempsey
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Scott B Ficarro
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Department of Cancer Biology and Blais Proteomics Center, Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | - William M Alexander
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Department of Cancer Biology and Blais Proteomics Center, Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | - Jarrod A Marto
- Department of Cancer Biology and Blais Proteomics Center, Dana-Farber Cancer Institute, Boston, MA 02115, USA; Department of Oncologic Pathology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Yana Li
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - L Mario Amzel
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA; Department of Oncology, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Sandra B Gabelli
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA; Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA; Department of Oncology, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA.
| | - Philip A Cole
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA; Department of Oncology, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA.
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13
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Baumruck AC, Tietze D, Steinacker LK, Tietze AA. Chemical synthesis of membrane proteins: a model study on the influenza virus B proton channel. Chem Sci 2018; 9:2365-2375. [PMID: 29719709 PMCID: PMC5897842 DOI: 10.1039/c8sc00004b] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2018] [Accepted: 01/21/2018] [Indexed: 12/16/2022] Open
Abstract
NCL results in the quantitative yield of a membrane protein, where a thioester peptide is formed from an oxo-ester with an in situ cleavable solubilizing tag.
In the present study we have developed and optimized a robust strategy for the synthesis of highly hydrophobic peptides, especially membrane proteins, exemplarily using the influenza B M2 proton channel (BM2(1–51)). This strategy is based on the native chemical ligation of two fragments, where the thioester fragment is formed from an oxo-ester peptide, which is synthesized using Fmoc-SPPS, and features an in situ cleavable solubilizing tag (ADO, ADO2 or ADO-Lys5). The nearly quantitative production of the ligation product was followed by an optimized work up protocol, resulting in almost quantitative desulfurization and Acm-group cleavage. Circular dichroism analysis in a POPC lipid membrane revealed that the synthetic BM2(1–51) construct adopts a helical structure similar to that of the previously characterized BM2(1–33).
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Affiliation(s)
- A C Baumruck
- Darmstadt University of Technology , Clemens-Schöpf Institute of Organic Chemistry and Biochemistry , Alarich-Weiss Str. 4 , 64287 Darmstadt , Germany .
| | - D Tietze
- Darmstadt University of Technology , Eduard-Zintl-Institute of Inorganic and Physical Chemistry , Alarich-Weiss-Str. 4 , 64287 Darmstadt , Germany
| | - L K Steinacker
- Darmstadt University of Technology , Clemens-Schöpf Institute of Organic Chemistry and Biochemistry , Alarich-Weiss Str. 4 , 64287 Darmstadt , Germany .
| | - A A Tietze
- Darmstadt University of Technology , Clemens-Schöpf Institute of Organic Chemistry and Biochemistry , Alarich-Weiss Str. 4 , 64287 Darmstadt , Germany .
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14
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Matveenko M, Hackl S, Becker CFW. Utility of the Phenacyl Protecting Group in Traceless Protein Semisynthesis through Ligation-Desulfurization Chemistry. ChemistryOpen 2018; 7:106-110. [PMID: 29321951 PMCID: PMC5759462 DOI: 10.1002/open.201700180] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 12/12/2017] [Indexed: 12/13/2022] Open
Abstract
Semisynthesis of proteins via expressed protein ligation is a widely applicable method, even more so because of the possibility of ligation at non-cysteine sites using β-mercapto amino acids that can be converted to the corresponding native amino acids by desulfurization. A drawback of this ligation- desulfurization approach is the removal of any unprotected native cysteine residues within the ligated protein segments. Here, we show that the phenacyl (PAc) moiety can be successfully used to protect cysteines within recombinantly generated protein segments. As such, this group was selectively appended onto cysteine side chains within bacterially expressed polypeptides following intein cleavage, which reveals a rather sensitive thioester at the C-terminus. The PAc group proved to be compatible with native chemical ligation, radical desulfurization, and reverse-phase HPLC conditions, and was smoothly removed at the end. The utility of the PAc protecting group was then demonstrated by the 'traceless' semisynthesis of two proteins containing one or two native cysteines: human small heat shock protein Hsp27 and murine prion protein.
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Affiliation(s)
- Maria Matveenko
- Institute of Biological Chemistry, Faculty of Chemistry University of Vienna Währinger Str. 38 1090 Vienna Austria
| | - Stefanie Hackl
- Institute of Biological Chemistry, Faculty of Chemistry University of Vienna Währinger Str. 38 1090 Vienna Austria
| | - Christian F W Becker
- Institute of Biological Chemistry, Faculty of Chemistry University of Vienna Währinger Str. 38 1090 Vienna Austria
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15
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Henninot A, Collins JC, Nuss JM. The Current State of Peptide Drug Discovery: Back to the Future? J Med Chem 2017; 61:1382-1414. [PMID: 28737935 DOI: 10.1021/acs.jmedchem.7b00318] [Citation(s) in RCA: 645] [Impact Index Per Article: 92.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Over the past decade, peptide drug discovery has experienced a revival of interest and scientific momentum, as the pharmaceutical industry has come to appreciate the role that peptide therapeutics can play in addressing unmet medical needs and how this class of compounds can be an excellent complement or even preferable alternative to small molecule and biological therapeutics. In this Perspective, we give a concise description of the recent progress in peptide drug discovery in a holistic manner, highlighting enabling technological advances affecting nearly every aspect of this field: from lead discovery, to synthesis and optimization, to peptide drug delivery. An emphasis is placed on describing research efforts to overcome the inherent weaknesses of peptide drugs, in particular their poor pharmacokinetic properties, and how these efforts have been critical to the discovery, design, and subsequent development of novel therapeutics.
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Affiliation(s)
- Antoine Henninot
- Ferring Research Institute , 4245 Sorrento Valley Boulevard, San Diego, California 92121, United States
| | - James C Collins
- Ferring Research Institute , 4245 Sorrento Valley Boulevard, San Diego, California 92121, United States
| | - John M Nuss
- Ferring Research Institute , 4245 Sorrento Valley Boulevard, San Diego, California 92121, United States
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16
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Araman C, Thompson RE, Wang S, Hackl S, Payne RJ, Becker CFW. Semisynthetic prion protein (PrP) variants carrying glycan mimics at position 181 and 197 do not form fibrils. Chem Sci 2017; 8:6626-6632. [PMID: 28989689 PMCID: PMC5625290 DOI: 10.1039/c7sc02719b] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 07/18/2017] [Indexed: 12/12/2022] Open
Abstract
Semisynthesis and characterization of homogeneously mono- and di-PEGylated full length PrP variants to study the impact of PEGylation (as N-glycan mimics) on protein folding and aggregation.
The prion protein (PrP) is an N-glycosylated protein attached to the outer leaflet of eukaryotic cell membranes via a glycosylphosphatidylinositol (GPI) anchor. Different prion strains have distinct glycosylation patterns and the extent of glycosylation of potentially pathogenic misfolded prion protein (PrPSc) has a major impact on several prion-related diseases (transmissible spongiform encephalopathies, TSEs). Based on these findings it is hypothesized that posttranslational modifications (PTMs) of PrP influence conversion of cellular prion protein (PrPC) into PrPSc and, as such, modified PrP variants are critical tools needed to investigate the impact of PTMs on the pathogenesis of TSEs. Here we report a semisynthetic approach to generate PrP variants modified with monodisperse polyethyleneglycol (PEG) units as mimics of N-glycans. Incorporating PEG at glycosylation sites 181 and 197 in PrP induced only small changes to the secondary structure when compared to unmodified, wildtype PrP. More importantly, in vitro aggregation was abrogated for all PEGylated PrP variants under conditions at which wildtype PrP aggregated. Furthermore, the addition of PEGylated PrP as low as 10 mol% to wildtype PrP completely blocked aggregation. A similar effect was observed for synthetic PEGylated PrP segments comprising amino acids 179–231 alone if these were added to wildtype PrP in aggregation assays. This behavior raises the question if large N-glycans interfere with aggregation in vivo and if PEGylated PrP peptides could serve as potential therapeutics.
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Affiliation(s)
- Can Araman
- Institute of Biological Chemistry , Department of Chemistry , University of Vienna , Waehringer Strasse 38 , 1090 , Vienna-AT , Austria .
| | - Robert E Thompson
- School of Chemistry , The University of Sydney , Sydney , NSW 2006 , Australia
| | - Siyao Wang
- School of Chemistry , The University of Sydney , Sydney , NSW 2006 , Australia
| | - Stefanie Hackl
- Institute of Biological Chemistry , Department of Chemistry , University of Vienna , Waehringer Strasse 38 , 1090 , Vienna-AT , Austria .
| | - Richard J Payne
- School of Chemistry , The University of Sydney , Sydney , NSW 2006 , Australia
| | - Christian F W Becker
- Institute of Biological Chemistry , Department of Chemistry , University of Vienna , Waehringer Strasse 38 , 1090 , Vienna-AT , Austria .
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17
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Sabareesan AT, Singh J, Roy S, Udgaonkar JB, Mathew MK. The Pathogenic A116V Mutation Enhances Ion-Selective Channel Formation by Prion Protein in Membranes. Biophys J 2017; 110:1766-1776. [PMID: 27119637 DOI: 10.1016/j.bpj.2016.03.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 02/23/2016] [Accepted: 03/07/2016] [Indexed: 11/19/2022] Open
Abstract
Prion diseases are a group of fatal neurodegenerative disorders that afflict mammals. Misfolded and aggregated forms of the prion protein (PrP(Sc)) have been associated with many prion diseases. A transmembrane form of PrP favored by the pathogenic mutation A116V is associated with Gerstmann-Sträussler-Scheinker syndrome, but no accumulation of PrP(Sc) is detected. However, the role of the transmembrane form of PrP in pathological processes leading to neuronal death remains unclear. This study reports that the full-length mouse PrP (moPrP) significantly increases the permeability of living cells to K(+), and forms K(+)- and Ca(2+)-selective channels in lipid membranes. Importantly, the pathogenic mutation A116V greatly increases the channel-forming capability of moPrP. The channels thus formed are impermeable to sodium and chloride ions, and are blocked by blockers of voltage-gated ion channels. Hydrogen-deuterium exchange studies coupled with mass spectrometry (HDX-MS) show that upon interaction with lipid, the central hydrophobic region (109-132) of the protein is protected against exchange, making it a good candidate for inserting into the membrane and lining the channel. HDX-MS also shows a dramatic increase in the protein-lipid stoichiometry for A116V moPrP, providing a rationale for its increased channel-forming capability. The results suggest that ion channel formation may be a possible mechanism of PrP-mediated neurodegeneration by the transmembrane forms of PrP.
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Affiliation(s)
- Ambadi Thody Sabareesan
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India
| | - Jogender Singh
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India
| | - Samrat Roy
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India; Biocon Bristol Myers Squibb Research Center, Bengaluru, India; School of Biotechnology, Kalinga Institute of Industrial Technology (KIIT) University, Bhubaneswar, India
| | - Jayant B Udgaonkar
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India.
| | - M K Mathew
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India.
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18
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Nyeste A, Stincardini C, Bencsura P, Cerovic M, Biasini E, Welker E. The prion protein family member Shadoo induces spontaneous ionic currents in cultured cells. Sci Rep 2016; 6:36441. [PMID: 27819308 PMCID: PMC5098206 DOI: 10.1038/srep36441] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 10/17/2016] [Indexed: 01/01/2023] Open
Abstract
Some mutant forms of the cellular prion protein (PrPC) carrying artificial deletions or point mutations associated with familial human prion diseases are capable of inducing spontaneous ionic currents across the cell membrane, conferring hypersensitivity to certain antibiotics to a wide range of cultured cells and primary cerebellar granular neurons (CGNs). These effects are abrogated when the wild type (WT) form is co-expressed, suggesting that they might be related to a physiological activity of PrPC. Interestingly, the prion protein family member Shadoo (Sho) makes cells hypersensitive to the same antibiotics as mutant PrP-s, an effect that is diminished by the co-expression of WT-PrP. Here, we report that Sho engages in another mutant PrP-like activity: it spontaneously induces large ionic currents in cultured SH-SY5Y cells, as detected by whole-cell patch clamping. These currents are also decreased by the co-expression of WT-PrP. Furthermore, deletion of the N-terminal (RXXX)8 motif of Sho, mutation of the eight arginine residues of this motif to glutamines, or replacement of the hydrophobic domain by that of PrP, also diminish Sho-induced ionic currents. Our results suggest that the channel activity that is also characteristic to some pathogenic PrP mutants may be linked to a physiological function of Sho.
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Affiliation(s)
- Antal Nyeste
- Institute of Biochemistry, Biological Research Center, Hungarian Academy of Sciences, Szeged, Hungary
- Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Claudia Stincardini
- Dulbecco Telethon Laboratory of Prions and Amyloids, Center for Integrative Biology (CIBIO), University of Trento, 38123 Trento, ITALY
| | - Petra Bencsura
- Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Milica Cerovic
- Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri, 20156 Milano, ITALY
| | - Emiliano Biasini
- Dulbecco Telethon Laboratory of Prions and Amyloids, Center for Integrative Biology (CIBIO), University of Trento, 38123 Trento, ITALY
- Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri, 20156 Milano, ITALY
| | - Ervin Welker
- Institute of Biochemistry, Biological Research Center, Hungarian Academy of Sciences, Szeged, Hungary
- Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
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19
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Hackl S, Schmid A, Becker CFW. Semisynthesis of Membrane-Attached Proteins Using Split Inteins. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2016; 1495:93-109. [PMID: 27714612 DOI: 10.1007/978-1-4939-6451-2_7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The site-selective installation of lipid modifications on proteins is critically important in our understanding of how membrane association influences the biophysical properties of proteins as well as to study certain proteins in their native environment. Here, we describe the use of split inteins for the C-terminal attachment of lipid-modified peptides to virtually any protein of interest (POI) via protein trans-splicing (PTS). To achieve this, the protein of interest is expressed in fusion with the N-terminal split intein segment and the C-terminal split intein segment is prepared by solid phase peptide synthesis. A synthetic peptide carrying two lipid chains is also made chemically to serve as a membrane anchor and subsequently linked to the C-terminal split intein by native chemical ligation. Proteins of interest for our work are the prion protein as well as small GTPases; however, extensions to other POIs are possible. Detailed information for the C-terminal introduction of a lipidated membrane anchor (MA) peptide using split intein systems from Synechocystis spp. and Nostoc punctiforme for the Prion protein (PrP, as a challenging protein of interest) and the enhanced green-fluorescent protein (eGFP, as an easily trackable target protein) are provided here.
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Affiliation(s)
- Stefanie Hackl
- Department of Chemistry, Institute of Biological Chemistry, University of Vienna, Waehringer Str. 38, 1090, Vienna, Austria
| | - Alanca Schmid
- Department of Chemistry, Institute of Biological Chemistry, University of Vienna, Waehringer Str. 38, 1090, Vienna, Austria
| | - Christian F W Becker
- Department of Chemistry, Institute of Biological Chemistry, University of Vienna, Waehringer Str. 38, 1090, Vienna, Austria.
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20
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Affiliation(s)
- Tom Mejuch
- Department
of Chemical Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
| | - Herbert Waldmann
- Department
of Chemical Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
- Department
of Chemistry and Chemical Biology, Technical University of Dortmund, Otto-Hahn-Strasse 6, 44227 Dortmund, Germany
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21
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Prion 2016 Poster Abstracts. Prion 2016; 10 Suppl 1:S37-S127. [PMID: 27088811 DOI: 10.1080/19336896.2016.1162644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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22
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Nyeste A, Bencsura P, Vida I, Hegyi Z, Homolya L, Fodor E, Welker E. Expression of the Prion Protein Family Member Shadoo Causes Drug Hypersensitivity That Is Diminished by the Coexpression of the Wild Type Prion Protein. J Biol Chem 2016; 291:4473-86. [PMID: 26721882 DOI: 10.1074/jbc.m115.679035] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Indexed: 11/06/2022] Open
Abstract
The prion protein (PrP) seems to exert both neuroprotective and neurotoxic activities. The toxic activities are associated with the C-terminal globular parts in the absence of the flexible N terminus, specifically the hydrophobic domain (HD) or the central region (CR). The wild type prion protein (PrP-WT), having an intact flexible part, exhibits neuroprotective qualities by virtue of diminishing many of the cytotoxic effects of these mutant prion proteins (PrPΔHD and PrPΔCR) when coexpressed. The prion protein family member Doppel, which possesses a three-dimensional fold similar to the C-terminal part of PrP, is also harmful to neuronal and other cells in various models, a phenotype that can also be eliminated by the coexpression of PrP-WT. In contrast, another prion protein family member, Shadoo (Sho), a natively disordered protein possessing structural features similar to the flexible N-terminal tail of PrP, exhibits PrP-WT-like protective properties. Here, we report that, contrary to expectations, Sho expression in SH-SY5Y or HEK293 cells induces the same toxic phenotype of drug hypersensitivity as PrPΔCR. This effect is exhibited in a dose-dependent manner and is also counteracted by the coexpression of PrP-WT. The opposing effects of Shadoo in different model systems revealed here may be explored to help discern the relationship of the various toxic activities of mutant PrPs with each other and the neurotoxic effects seen in neurodegenerative diseases, such as transmissible spongiform encephalopathy and Alzheimer disease.
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Affiliation(s)
- Antal Nyeste
- From the Institute of Biochemistry, Biological Research Center, Hungarian Academy of Sciences, H-6726 Szeged, Hungary
| | - Petra Bencsura
- the Research Centre for Natural Sciences, Hungarian Academy of Sciences, H-1117 Budapest, Hungary, and
| | - István Vida
- the Research Centre for Natural Sciences, Hungarian Academy of Sciences, H-1117 Budapest, Hungary, and the Institute of Chemistry, Eötvös Loránd University, H-1117 Budapest, Hungary
| | - Zoltán Hegyi
- the Research Centre for Natural Sciences, Hungarian Academy of Sciences, H-1117 Budapest, Hungary, and
| | - László Homolya
- the Research Centre for Natural Sciences, Hungarian Academy of Sciences, H-1117 Budapest, Hungary, and
| | - Elfrieda Fodor
- From the Institute of Biochemistry, Biological Research Center, Hungarian Academy of Sciences, H-6726 Szeged, Hungary
| | - Ervin Welker
- From the Institute of Biochemistry, Biological Research Center, Hungarian Academy of Sciences, H-6726 Szeged, Hungary, the Research Centre for Natural Sciences, Hungarian Academy of Sciences, H-1117 Budapest, Hungary, and
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23
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Schäfer B, Orbán E, Fiser G, Marton A, Vizler C, Tömböly C. Semisynthesis of membrane-anchored cholesteryl lipoproteins on live cell surface by azide–alkyne click reaction. Tetrahedron Lett 2016. [DOI: 10.1016/j.tetlet.2016.01.041] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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