1
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Regmi D, Shen F, Stanic A, Islam M, Du D. Effect of phospholipid liposomes on prion fragment (106-128) amyloid formation. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2023; 1865:184199. [PMID: 37454869 DOI: 10.1016/j.bbamem.2023.184199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 06/08/2023] [Accepted: 07/11/2023] [Indexed: 07/18/2023]
Abstract
Misfolding and aggregation of cellular prion protein (PrPc) is a major molecular process involved in the pathogenesis of prion diseases. Here, we studied the aggregation properties of a prion fragment peptide PrP(106-128). The results show that the peptide aggregates in a concentration-dependent manner in an aqueous solution and that the aggregation is sensitive to pH and the preformed amyloid seeds. Furthermore, we show that the zwitterionic POPC liposomes moderately inhibit the aggregation of PrP(106-128), whereas POPC/cholesterol (8:2) vesicles facilitate peptide aggregation likely due to the increase of the lipid packing order and membrane rigidity in the presence of cholesterol. In addition, anionic lipid vesicles of POPG and POPG/cholesterol above a certain concentration accelerate the aggregation of the peptide remarkably. The strong electrostatic interactions between the N-terminal region of the peptide and POPG may constrain the conformational plasticity of the peptide, preventing insertion of the peptide into the inner side of the membrane and thus promoting fibrillation on the membrane surface. The results suggest that the charge properties of the membrane, the composition of the liposomes, and the rigidity of lipid packing are critical in determining peptide adsorption on the membrane surface and the efficiency of the membrane in catalyzing peptide oligomeric nucleation and amyloid formation. The peptide could be used as an improved model molecule to investigate the mechanistic role of the crucial regions of PrP in aggregation in a membrane-rich environment and to screen effective inhibitors to block key interactions between these regions and membranes for preventing PrP aggregation.
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Affiliation(s)
- Deepika Regmi
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, FL 33431, USA
| | - Fengyun Shen
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, FL 33431, USA
| | - Aleksander Stanic
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, FL 33431, USA
| | - Majedul Islam
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, FL 33431, USA
| | - Deguo Du
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, FL 33431, USA.
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2
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Bacchella C, Dell'Acqua S, Nicolis S, Monzani E, Casella L. The reactivity of copper complexes with neuronal peptides promoted by catecholamines and its impact on neurodegeneration. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2022.214756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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3
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Loh D, Reiter RJ. Melatonin: Regulation of Prion Protein Phase Separation in Cancer Multidrug Resistance. Molecules 2022; 27:705. [PMID: 35163973 PMCID: PMC8839844 DOI: 10.3390/molecules27030705] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/11/2022] [Accepted: 01/17/2022] [Indexed: 12/13/2022] Open
Abstract
The unique ability to adapt and thrive in inhospitable, stressful tumor microenvironments (TME) also renders cancer cells resistant to traditional chemotherapeutic treatments and/or novel pharmaceuticals. Cancer cells exhibit extensive metabolic alterations involving hypoxia, accelerated glycolysis, oxidative stress, and increased extracellular ATP that may activate ancient, conserved prion adaptive response strategies that exacerbate multidrug resistance (MDR) by exploiting cellular stress to increase cancer metastatic potential and stemness, balance proliferation and differentiation, and amplify resistance to apoptosis. The regulation of prions in MDR is further complicated by important, putative physiological functions of ligand-binding and signal transduction. Melatonin is capable of both enhancing physiological functions and inhibiting oncogenic properties of prion proteins. Through regulation of phase separation of the prion N-terminal domain which targets and interacts with lipid rafts, melatonin may prevent conformational changes that can result in aggregation and/or conversion to pathological, infectious isoforms. As a cancer therapy adjuvant, melatonin could modulate TME oxidative stress levels and hypoxia, reverse pH gradient changes, reduce lipid peroxidation, and protect lipid raft compositions to suppress prion-mediated, non-Mendelian, heritable, but often reversible epigenetic adaptations that facilitate cancer heterogeneity, stemness, metastasis, and drug resistance. This review examines some of the mechanisms that may balance physiological and pathological effects of prions and prion-like proteins achieved through the synergistic use of melatonin to ameliorate MDR, which remains a challenge in cancer treatment.
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Affiliation(s)
- Doris Loh
- Independent Researcher, Marble Falls, TX 78654, USA
| | - Russel J. Reiter
- Department of Cellular and Structural Biology, UT Health San Antonio, San Antonio, TX 78229, USA
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4
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Shoup D, Priola SA. The Size and Stability of Infectious Prion Aggregates Fluctuate Dynamically during Cellular Uptake and Disaggregation. Biochemistry 2021; 60:398-411. [PMID: 33497187 DOI: 10.1021/acs.biochem.0c00923] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Prion diseases arise when PrPSc, an aggregated, infectious, and insoluble conformer of the normally soluble mammalian prion protein, PrPC, catalyzes the conversion of PrPC into more PrPSc, which then accumulates in the brain leading to disease. PrPSc is the primary, if not sole, component of the infectious prion. Despite the stability and protease insensitivity of PrPSc aggregates, they can be degraded after cellular uptake. However, how cells disassemble and degrade PrPSc is poorly understood. In this work, we analyzed how the protease sensitivity and size distribution of PrPSc aggregates from two different mouse-adapted prion strains, 22L, that can persistently infect cells and 87V, that cannot, changed during cellular uptake. We show that within the first 4 h following uptake large PrPSc aggregates from both prion strains become less resistant to digestion by proteinase K (PK) through a mechanism that is dependent upon the acidic environment of endocytic vesicles. We further show that during disassembly, PrPSc aggregates from both strains become more resistant to PK digestion through the apparent removal of protease-sensitive PrPSc, with PrPSc from the 87V strain disassembled more readily than PrPSc from the 22L strain. Taken together, our data demonstrate that the sizes and stabilities of PrPSc from different prion strains change during cellular uptake and degradation, thereby potentially impacting the ability of prions to infect cells.
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Affiliation(s)
- Daniel Shoup
- Rocky Mountain Laboratories, Laboratory of Persistent Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana 59840, United States
| | - Suzette A Priola
- Rocky Mountain Laboratories, Laboratory of Persistent Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana 59840, United States
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5
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Carroll JA, Groveman BR, Williams K, Moore R, Race B, Haigh CL. Prion protein N1 cleavage peptides stimulate microglial interaction with surrounding cells. Sci Rep 2020; 10:6654. [PMID: 32313035 PMCID: PMC7171115 DOI: 10.1038/s41598-020-63472-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 03/29/2020] [Indexed: 01/06/2023] Open
Abstract
Microglia act as the protective immune cell of the brain. By surveying the tissue to identify and rectify problems, they function to maintain the health of brain cells. The prion protein N-terminal cleavage fragment, N1, has demonstrated neuroprotective activities in vitro and in vivo. This study aimed to elucidate whether N1 could modulate microglial function and, if so, determine the consequences for the surrounding tissue. Using a mixed neuronal lineage and microglia co-culture system, we showed that N1 stimulation changed overall morphology and metabolism, suggesting enhanced cellular viability. Furthermore, N1 induced an increase in Cxcl10 secretion in the co-cultures. Recombinant Cxcl10, administered exogenously, mediated the changes in the mixed neuronal lineage culture morphology and metabolism in the absence of microglia, but no effect of Cxcl10 was observed on microglia cultured on their own. Direct cell-to-cell contact was required for N1 to influence microglia in the co-cultures, and this was linked with restructuring of microglial membrane composition to include a higher GM1 content at interaction sites with surrounding cells. Our findings show that N1 can play a regulatory role in microglial function in the context of an inter-connected network of cells by changing both cellular interaction sites and cytokine secretion.
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Affiliation(s)
- J A Carroll
- Laboratory of Persistent Viral Diseases, National Institute of Allergy and Infectious Diseases, Division of Intramural Research, Rocky Mountain Laboratories, National Institutes of Health, 903 South 4th Street, Hamilton, MT, 59840, USA
| | - B R Groveman
- Laboratory of Persistent Viral Diseases, National Institute of Allergy and Infectious Diseases, Division of Intramural Research, Rocky Mountain Laboratories, National Institutes of Health, 903 South 4th Street, Hamilton, MT, 59840, USA
| | - K Williams
- Laboratory of Persistent Viral Diseases, National Institute of Allergy and Infectious Diseases, Division of Intramural Research, Rocky Mountain Laboratories, National Institutes of Health, 903 South 4th Street, Hamilton, MT, 59840, USA
| | - R Moore
- Laboratory of Persistent Viral Diseases, National Institute of Allergy and Infectious Diseases, Division of Intramural Research, Rocky Mountain Laboratories, National Institutes of Health, 903 South 4th Street, Hamilton, MT, 59840, USA
| | - B Race
- Laboratory of Persistent Viral Diseases, National Institute of Allergy and Infectious Diseases, Division of Intramural Research, Rocky Mountain Laboratories, National Institutes of Health, 903 South 4th Street, Hamilton, MT, 59840, USA
| | - C L Haigh
- Laboratory of Persistent Viral Diseases, National Institute of Allergy and Infectious Diseases, Division of Intramural Research, Rocky Mountain Laboratories, National Institutes of Health, 903 South 4th Street, Hamilton, MT, 59840, USA.
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6
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Bacchella C, Nicolis S, Dell'Acqua S, Rizzarelli E, Monzani E, Casella L. Membrane Binding Strongly Affecting the Dopamine Reactivity Induced by Copper Prion and Copper/Amyloid-β (Aβ) Peptides. A Ternary Copper/Aβ/Prion Peptide Complex Stabilized and Solubilized in Sodium Dodecyl Sulfate Micelles. Inorg Chem 2019; 59:900-912. [PMID: 31869218 DOI: 10.1021/acs.inorgchem.9b03153] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The combination between dyshomeostatic levels of catecholamine neurotransmitters and redox-active metals such as copper and iron exacerbates the oxidative stress condition that typically affects neurodegenerative diseases. We report a comparative study of the oxidative reactivity of copper complexes with amyloid-β (Aβ40) and the prion peptide fragment 76-114 (PrP76-114), containing the high-affinity binding site, toward dopamine and 4-methylcatechol, in aqueous buffer and in sodium dodecyl sulfate micelles, as a model membrane environment. The competitive oxidative and covalent modifications undergone by the peptides were also evaluated. The high binding affinity of Cu/peptide to micelles and lipid membranes leads to a strong reduction (Aβ40) and quenching (PrP76-114) of the oxidative efficiency of the binary complexes and to a stabilization and redox silencing of the ternary complex CuII/Aβ40/PrP76-114, which is highly reactive in solution. The results improve our understanding of the pathological and protective effects associated with these complexes, depending on the physiological environment.
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Affiliation(s)
- Chiara Bacchella
- Dipartimento di Chimica , Università di Pavia , Via Taramelli 12 , 27100 Pavia , Italy
| | - Stefania Nicolis
- Dipartimento di Chimica , Università di Pavia , Via Taramelli 12 , 27100 Pavia , Italy
| | - Simone Dell'Acqua
- Dipartimento di Chimica , Università di Pavia , Via Taramelli 12 , 27100 Pavia , Italy
| | - Enrico Rizzarelli
- Istituto di Biostrutture e Bioimmagini , Consiglio Nazionale delle Ricerche , Via P. Gaifami 18 , 95125 Catania , Italy
| | - Enrico Monzani
- Dipartimento di Chimica , Università di Pavia , Via Taramelli 12 , 27100 Pavia , Italy
| | - Luigi Casella
- Dipartimento di Chimica , Università di Pavia , Via Taramelli 12 , 27100 Pavia , Italy
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7
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Magrì A, Tabbì G, Cucci LM, Satriano C, Pietropaolo A, Malgieri G, Isernia C, La Mendola D. The curious case of opossum prion: a physicochemical study on copper(ii) binding to the bis-decarepeat fragment from the protein N-terminal domain. Dalton Trans 2019; 48:17533-17543. [PMID: 31748763 DOI: 10.1039/c9dt02510c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The opossum is a peculiar model of immunity to prion diseases. Here we scrutinised the bis-decarepeat peptide sequence of the opossum prion (Op_bis-deca) protein by a multitechnique approach, with a combined experimental (potentiometry, UV-visible, circular dichroism, NMR and EPR spectroscopy, quartz crystal microbalance with dissipation monitoring and confocal microscopy) and simulation (DFT calculations) approach. Results showed that the macrochelate structures formed upon the binding to Cu(ii) by the analogous bis-octarepeat peptide sequence of human prion (Hu_bis-octa) are not found in the case of Op_bis-deca. At physiological pH and equimolar amount of copper ions, the [CuLH-2] is the major species formed by Op_bis-deca. In this species one imidazole and two amide nitrogen atoms are involved in metal coordination and its stability constant value is lower than that of the analogous species formed by Hu_bis-octa, due to the presence of an extra proline residue. Moreover, the study on the interaction of the peptides or the peptide/Cu(ii) complexes with the model cell membranes made of supported lipid bilayers disclosed different levels of interaction, monitored by the viscoelastic changes of the membranes, which exhibited a similar viscoelastic response at the interface of the two complexes, while in the absence of Cu(ii), the Hu_bis-octa/SLB interface was more viscoelastic than the Op_bis-deca one.
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Affiliation(s)
- Antonio Magrì
- Institute of Crystallography, National Research Council (CNR), S.S. Catania, Via P. Gaifami 18, 95126 Catania, Italy
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8
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Pan Y, Wang B, Reese RA, Xu B. The molecular basis of interaction domains of full-length PrP with lipid membranes. NANOSCALE 2019; 11:12087-12091. [PMID: 31204758 DOI: 10.1039/c9nr02735a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
PrP-lipid membrane interactions are critical to PrP structural conversion and neurotoxicity, but its molecular mechanism remains unclear. A two-dimensional histogram of force-distance curves and a worm-like chain model revealed three binding regions at the PrP N-terminal, providing the molecular basis for understanding the interactions between full-length PrP and lipid membranes.
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Affiliation(s)
- Yangang Pan
- Single Molecule Study Lab., College of Engineering, University of Georgia, Athens, GA 30602, USA. and Department of Pharmaceutical Sciences, University of Nebraska, Omaha, NE 68195, USA
| | - Bin Wang
- Single Molecule Study Lab., College of Engineering, University of Georgia, Athens, GA 30602, USA. and United States Department of Agriculture, Agricultural Research Service, National Poultry Research Canter, Athens, GA 30605, USA
| | - R Alexander Reese
- Single Molecule Study Lab., College of Engineering, University of Georgia, Athens, GA 30602, USA.
| | - Bingqian Xu
- Single Molecule Study Lab., College of Engineering, University of Georgia, Athens, GA 30602, USA.
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9
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Collins SJ, Tumpach C, Groveman BR, Drew SC, Haigh CL. Prion protein cleavage fragments regulate adult neural stem cell quiescence through redox modulation of mitochondrial fission and SOD2 expression. Cell Mol Life Sci 2018; 75:3231-3249. [PMID: 29574582 PMCID: PMC6063333 DOI: 10.1007/s00018-018-2790-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 02/27/2018] [Accepted: 03/05/2018] [Indexed: 01/06/2023]
Abstract
Neurogenesis continues in the post-developmental brain throughout life. The ability to stimulate the production of new neurones requires both quiescent and actively proliferating pools of neural stem cells (NSCs). Actively proliferating NSCs ensure that neurogenic demand can be met, whilst the quiescent pool makes certain NSC reserves do not become depleted. The processes preserving the NSC quiescent pool are only just beginning to be defined. Herein, we identify a switch between NSC proliferation and quiescence through changing intracellular redox signalling. We show that N-terminal post-translational cleavage products of the prion protein (PrP) induce a quiescent state, halting NSC cellular growth, migration, and neurite outgrowth. Quiescence is initiated by the PrP cleavage products through reducing intracellular levels of reactive oxygen species. First, inhibition of redox signalling results in increased mitochondrial fission, which rapidly signals quiescence. Thereafter, quiescence is maintained through downstream increases in the expression and activity of superoxide dismutase-2 that reduces mitochondrial superoxide. We further observe that PrP is predominantly cleaved in quiescent NSCs indicating a homeostatic role for this cascade. Our findings provide new insight into the regulation of NSC quiescence, which potentially could influence brain health throughout adult life.
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Affiliation(s)
- Steven J Collins
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Carolin Tumpach
- Doherty Institute, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Bradley R Groveman
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, 59840, USA
| | - Simon C Drew
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Cathryn L Haigh
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Melbourne, VIC, 3010, Australia.
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, 59840, USA.
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10
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Mechanism of aggregation and membrane interactions of mammalian prion protein. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018. [DOI: 10.1016/j.bbamem.2018.02.031] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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11
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Linsenmeier L, Altmeppen HC, Wetzel S, Mohammadi B, Saftig P, Glatzel M. Diverse functions of the prion protein - Does proteolytic processing hold the key? BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:2128-2137. [PMID: 28693923 DOI: 10.1016/j.bbamcr.2017.06.022] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 06/27/2017] [Accepted: 06/29/2017] [Indexed: 02/07/2023]
Abstract
Proteolytic processing of the cellular and disease-associated form of the prion protein leads to generation of bioactive soluble prion protein fragments and modifies the structure and function of its cell-bound form. The nature of proteases responsible for shedding, α-, β-, and γ-cleavage of the prion protein are only partially identified and their regulation is largely unknown. Here, we provide an overview of the increasingly multifaceted picture of prion protein proteolysis and shed light on physiological and pathological roles associated with these cleavages. This article is part of a Special Issue entitled: Proteolysis as a Regulatory Event in Pathophysiology edited by Stefan Rose-John.
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Affiliation(s)
- Luise Linsenmeier
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Hermann C Altmeppen
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Sebastian Wetzel
- Institute of Biochemistry, Christian Albrechts University Kiel, Kiel, Germany
| | - Behnam Mohammadi
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Paul Saftig
- Institute of Biochemistry, Christian Albrechts University Kiel, Kiel, Germany
| | - Markus Glatzel
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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12
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Cheng CJ, Koldsø H, Van der Kamp MW, Schiøtt B, Daggett V. Simulations of membrane-bound diglycosylated human prion protein reveal potential protective mechanisms against misfolding. J Neurochem 2017; 142:171-182. [PMID: 28407243 DOI: 10.1111/jnc.14044] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 03/28/2017] [Accepted: 03/28/2017] [Indexed: 01/06/2023]
Abstract
Prion diseases are associated with the misfolding of the prion protein (PrP) from its normal cellular form (PrPC ) to its infectious scrapie form (PrPSc ). Post-translational modifications in PrP in vivo can play an important role in modulating the process of misfolding. To gain more insight into the effects of post-translational modifications in PrP structure and dynamics and to test the hypothesis that such modifications can interact with the protein, we have performed molecular dynamics simulations of diglycosylated human PrPC bound to a lipid bilayer via a glycophosphatidylinositol anchor. Multiple simulations were performed at three different pH ranges to explore pH effects on structure and dynamics. In contrast to simulations of protein-only PrPC , no large effects were observed upon lowering the pH of the system. The protein tilted toward the membrane surface in all of the simulations and the putative PrPSc oligomerization sites became inaccessible, thereby offering a possible protective mechanism against PrPSc -induced misfolding of PrPC .
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Affiliation(s)
- Chin Jung Cheng
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
| | - Heidi Koldsø
- Department of Bioengineering, University of Washington, Seattle, Washington, USA.,Department of Chemistry, inSPIN and iNANO Centers, Aarhus University, Aarhus C, Denmark
| | - Marc W Van der Kamp
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
| | - Birgit Schiøtt
- Department of Chemistry, inSPIN and iNANO Centers, Aarhus University, Aarhus C, Denmark
| | - Valerie Daggett
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
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13
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Arkhipenko A, Syan S, Victoria GS, Lebreton S, Zurzolo C. PrPC Undergoes Basal to Apical Transcytosis in Polarized Epithelial MDCK Cells. PLoS One 2016; 11:e0157991. [PMID: 27389581 PMCID: PMC4936696 DOI: 10.1371/journal.pone.0157991] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 06/08/2016] [Indexed: 01/05/2023] Open
Abstract
The Prion Protein (PrP) is an ubiquitously expressed glycosylated membrane protein attached to the external leaflet of the plasma membrane via a glycosylphosphatidylinositol anchor (GPI). While the misfolded PrPSc scrapie isoform is the infectious agent of prion disease, the cellular isoform (PrPC) is an enigmatic protein with unclear function. Of interest, PrP localization in polarized MDCK cells is controversial and its mechanism of trafficking is not clear. Here we investigated PrP traffic in MDCK cells polarized on filters and in three-dimensional MDCK cysts, a more physiological model of polarized epithelia. We found that, unlike other GPI-anchored proteins (GPI-APs), PrP undergoes basolateral-to-apical transcytosis in fully polarized MDCK cells. Following this event full-length PrP and its cleavage fragments are segregated in different domains of the plasma membrane in polarized cells in both 2D and 3D cultures.
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Affiliation(s)
- Alexander Arkhipenko
- Unité de Trafic Membranaire et Pathogénèse, Institut Pasteur, 25-28 rue du docteur Roux, 75015, Paris, France
| | - Sylvie Syan
- Unité de Trafic Membranaire et Pathogénèse, Institut Pasteur, 25-28 rue du docteur Roux, 75015, Paris, France
| | - Guiliana Soraya Victoria
- Unité de Trafic Membranaire et Pathogénèse, Institut Pasteur, 25-28 rue du docteur Roux, 75015, Paris, France
| | - Stéphanie Lebreton
- Unité de Trafic Membranaire et Pathogénèse, Institut Pasteur, 25-28 rue du docteur Roux, 75015, Paris, France
| | - Chiara Zurzolo
- Unité de Trafic Membranaire et Pathogénèse, Institut Pasteur, 25-28 rue du docteur Roux, 75015, Paris, France
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14
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Pan Y, Wang B, Zhang T, Zhang Y, Wang H, Xu B. Nanoscale insights into full-length prion protein aggregation on model lipid membranes. Chem Commun (Camb) 2016; 52:8533-6. [DOI: 10.1039/c6cc03029g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The aggregates of the full-length human recombinant prion protein (PrP) (23–231) on model membranes were investigated by combining the atomic force microscopy (AFM) measurements and theoretical calculations at pH 5.0, showing the great effect of PrP concentration on its supramolecular assemblies on the lipid bilayer.
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Affiliation(s)
- Yangang Pan
- Single Molecule Study Laboratory
- Faculty of Engineering and Nanoscale Science and Engineering Center
- University of Georgia
- Athens
- USA
| | - Bin Wang
- Single Molecule Study Laboratory
- Faculty of Engineering and Nanoscale Science and Engineering Center
- University of Georgia
- Athens
- USA
| | - Tong Zhang
- Single Molecule Study Laboratory
- Faculty of Engineering and Nanoscale Science and Engineering Center
- University of Georgia
- Athens
- USA
| | - Yanan Zhang
- Single Molecule Study Laboratory
- Faculty of Engineering and Nanoscale Science and Engineering Center
- University of Georgia
- Athens
- USA
| | - Hongda Wang
- State Key Laboratory of Electroanalytical Chemistry
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
- P. R. China
| | - Bingqian Xu
- Single Molecule Study Laboratory
- Faculty of Engineering and Nanoscale Science and Engineering Center
- University of Georgia
- Athens
- USA
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15
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Martínez J, Sánchez R, Castellanos M, Makarava N, Aguzzi A, Baskakov IV, Gasset M. PrP charge structure encodes interdomain interactions. Sci Rep 2015; 5:13623. [PMID: 26323476 PMCID: PMC4555102 DOI: 10.1038/srep13623] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 07/31/2015] [Indexed: 11/19/2022] Open
Abstract
Almost all proteins contain charged residues, and their chain distribution is tailored to fulfill essential ionic interactions for folding, binding and catalysis. Among proteins, the hinged two-domain chain of the cellular prion protein (PrPC) exhibits a peculiar charge structure with unclear consequences in its structural malleability. To decipher the charge design role, we generated charge-reverted mutants for each domain and analyzed their effect on conformational and metabolic features. We found that charges contain the information for interdomain interactions. Use of dynamic light scattering and thermal denaturation experiments delineates the compaction of the α-fold by an electrostatic compensation between the polybasic 23–30 region and the α3 electronegative surface. This interaction increases stability and disfavors fibrillation. Independently of this structural effect, the N-terminal electropositive clusters regulate the α-cleavage efficiency. In the fibrillar state, use of circular dichroism, atomic-force and fluorescence microscopies reveal that the N-terminal positive clusters and the α3 electronegative surface dictate the secondary structure, the assembly hierarchy and the growth length of the fibril state. These findings show that the PrP charge structure functions as a code set up to ensure function and reduce pathogenic routes.
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Affiliation(s)
- Javier Martínez
- Instituto Química-Física "Rocasolano", Consejo Superior de Investigaciones Científicas, Madrid 28006, Spain
| | - Rosa Sánchez
- Instituto Química-Física "Rocasolano", Consejo Superior de Investigaciones Científicas, Madrid 28006, Spain
| | - Milagros Castellanos
- Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain; IMDEA-Nanociencia, Madrid 28049, Spain
| | - Natallia Makarava
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Adriano Aguzzi
- Institute of Neuropathology, University Hospital of Zürich, Zürich 8091, Switzerland
| | - Ilia V Baskakov
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - María Gasset
- Instituto Química-Física "Rocasolano", Consejo Superior de Investigaciones Científicas, Madrid 28006, Spain
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16
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Haigh CL, Tumpach C, Drew SC, Collins SJ. The Prion Protein N1 and N2 Cleavage Fragments Bind to Phosphatidylserine and Phosphatidic Acid; Relevance to Stress-Protection Responses. PLoS One 2015; 10:e0134680. [PMID: 26252007 PMCID: PMC4529310 DOI: 10.1371/journal.pone.0134680] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 07/13/2015] [Indexed: 11/18/2022] Open
Abstract
Internal cleavage of the cellular prion protein generates two well characterised N-terminal fragments, N1 and N2. These fragments have been shown to bind to anionic phospholipids at low pH. We sought to investigate binding with other lipid moieties and queried how such interactions could be relevant to the cellular functions of these fragments. Both N1 and N2 bound phosphatidylserine (PS), as previously reported, and a further interaction with phosphatidic acid (PA) was also identified. The specificity of this interaction required the N-terminus, especially the proline motif within the basic amino acids at the N-terminus, together with the copper-binding region (unrelated to copper saturation). Previously, the fragments have been shown to be protective against cellular stresses. In the current study, serum deprivation was used to induce changes in the cellular lipid environment, including externalisation of plasma membrane PS and increased cellular levels of PA. When copper-saturated, N2 could reverse these changes, but N1 could not, suggesting that direct binding of N2 to cellular lipids may be part of the mechanism by which this peptide signals its protective response.
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Affiliation(s)
- Cathryn L. Haigh
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Melbourne Brain Centre, Melbourne, VIC, AUS, 3010
- * E-mail: (CLH); (SJC)
| | - Carolin Tumpach
- The Florey Department of Neuroscience and Mental Health, The University of Melbourne, Melbourne Brain Centre, Melbourne, VIC, AUS, 3010
| | - Simon C. Drew
- The Florey Department of Neuroscience and Mental Health, The University of Melbourne, Melbourne Brain Centre, Melbourne, VIC, AUS, 3010
| | - Steven J. Collins
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Melbourne Brain Centre, Melbourne, VIC, AUS, 3010
- The Florey Department of Neuroscience and Mental Health, The University of Melbourne, Melbourne Brain Centre, Melbourne, VIC, AUS, 3010
- * E-mail: (CLH); (SJC)
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17
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Hatty CR, Banati RB. Protein-ligand and membrane-ligand interactions in pharmacology: the case of the translocator protein (TSPO). Pharmacol Res 2015; 100:58-63. [PMID: 26238176 DOI: 10.1016/j.phrs.2015.07.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 07/28/2015] [Accepted: 07/29/2015] [Indexed: 11/30/2022]
Abstract
The targets of many small molecule drugs are membrane proteins, and traditionally the focus of pharmacology is on the interaction between such receptors and their small molecule drug ligands. However, the lipid membranes of cells and organelles are increasingly appreciated as diverse and dynamic structures that also specifically interact with small molecule drugs and peptides, causing profound changes in the properties of these membranes, and modulating the function of the membrane and the proteins within it. Drug-membrane interactions are likely to have a role in both the therapeutic and toxic activity of a variety of compounds, and their role in the overall pharmacological effect of a drug needs to be understood more clearly. This is the case for the 18 kDa translocator protein (TSPO) and its ligands, where functions that were established based on pharmacological studies are being called into question. Re-examining the putative functions of the TSPO and the effects of its ligands reveals a need to consider in more detail the interplay between protein-ligand and membrane-ligand interactions, and the modulatory relationship between TSPO and the lipid membrane.
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Affiliation(s)
- Claire R Hatty
- Medical Imaging & Radiation Sciences Faculty Research Group, Faculty of Health Sciences, The University of Sydney, Brain & Mind Research Institute, 94 Mallett Street, Camperdown, NSW 2050, Australia.
| | - Richard B Banati
- Medical Imaging & Radiation Sciences Faculty Research Group, Faculty of Health Sciences, The University of Sydney, Brain & Mind Research Institute, 94 Mallett Street, Camperdown, NSW 2050, Australia; Life Sciences, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234, Australia
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18
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Mittag D, Sran A, Chan KS, Boland MP, Bandala-Sanchez E, Huet O, Xu W, Sparrow RL. Stored red blood cell susceptibility to in vitro transfusion-associated stress conditions is higher after longer storage and increased by storage in saline-adenine-glucose-mannitol compared to AS-1. Transfusion 2015; 55:2197-206. [PMID: 25968419 DOI: 10.1111/trf.13138] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Revised: 02/23/2015] [Accepted: 02/28/2015] [Indexed: 12/25/2022]
Abstract
BACKGROUND Biochemical changes induced in red blood cells (RBCs) during storage may impair their function upon transfusion. Transfusion-associated stresses may further amplify storage lesion effects including increased phosphatidylserine (PS) exposure at the RBC membrane, microparticle (MP) release, and adhesion to endothelial cells (ECs). RBC stress susceptibility in vitro was investigated in relation to storage time and additive solution. STUDY DESIGN AND METHODS Leukoreduced whole blood donations (n = 18) were paired, mixed, and resplit before separating the RBCs for storage in saline-adenine-glucose-mannitol (SAGM) or AS-1. Samples were taken after 3, 21, or 35 days. For oxidative stress treatment, RBCs were exposed to 0.5 mmol/L tert-butylhydroperoxide. Transfusion-associated stress was simulated by overnight culture at 37 °C with plasma containing inflammatory mediators. PS exposure and MPs were measured by flow cytometry and adhesion to ECs was tested under flow conditions. PS specificity of adhesion was tested by blocking with PS-containing lipid vesicles. RESULTS Oxidative stress induced significantly higher PS exposure and adhesion to ECs in RBCs stored for 35 days compared to 3 days (p < 0.04). PS-containing vesicles blocked RBC-EC adhesion. After overnight culture with or without plasma, PS exposure and EC adhesion were significantly increased (p < 0.05). MP numbers increased with longer RBC storage and after RBC culture with plasma. Culture conditions influenced MP numbers from Day 35 RBCs. RBCs stored in SAGM had significantly higher PS exposure after stress treatment than AS-1 RBCs (p < 0.02). CONCLUSION Storage for 35 days significantly increased RBC susceptibility to oxidative and in vitro transfusion-associated stresses and was higher for RBCs stored in SAGM compared to AS-1.
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Affiliation(s)
- Diana Mittag
- formerly Research and Development, Australian Red Cross Blood Service, West Melbourne, Victoria, Australia
| | - Amrita Sran
- formerly Research and Development, Australian Red Cross Blood Service, West Melbourne, Victoria, Australia
| | - Kasey S Chan
- formerly Research and Development, Australian Red Cross Blood Service, West Melbourne, Victoria, Australia
| | - Martin P Boland
- School of Psychological and Clinical Sciences, Charles Darwin University, Darwin, Northern Territory, Australia
| | - Esther Bandala-Sanchez
- Department of Medical Biology, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
| | - Olivier Huet
- Baker IDI Heart and Diabetes Institute, Melbourne, Victoria
| | - William Xu
- formerly Research and Development, Australian Red Cross Blood Service, West Melbourne, Victoria, Australia
| | - Rosemary L Sparrow
- formerly Research and Development, Australian Red Cross Blood Service, West Melbourne, Victoria, Australia.,Department of Immunology, Monash University, Melbourne, Victoria, Australia
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19
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Haigh CL, McGlade AR, Collins SJ. MEK1 transduces the prion protein N2 fragment antioxidant effects. Cell Mol Life Sci 2015; 72:1613-29. [PMID: 25391659 PMCID: PMC11114014 DOI: 10.1007/s00018-014-1777-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 10/13/2014] [Accepted: 11/06/2014] [Indexed: 10/24/2022]
Abstract
The prion protein (PrP(C)) when mis-folded is causally linked with a group of fatal neurodegenerative diseases called transmissible spongiform encephalopathies or prion diseases. PrP(C) normal function is still incompletely defined with such investigations complicated by PrP(C) post-translational modifications, such as internal cleavage, which feasibly could change, activate, or deactivate the function of this protein. Oxidative stress induces β-cleavage and the N-terminal product of this cleavage event, N2, demonstrates a cellular protective response against oxidative stress. The mechanisms by which N2 mediates cellular antioxidant protection were investigated within an in vitro cell model. N2 protection was regulated by copper binding to the octarepeat domain, directing the route of internalisation, which stimulated MEK1 signalling. Precise membrane interactions of N2, determined by copper saturation, and involving both the copper-co-ordinating octarepeat region and the structure conferred upon the N-terminal polybasic region by the proline motif, were essential for the correct engagement of this pathway. The phenomenon of PrP(C) post-translational modification, such as cleavage and copper co-ordination, as a molecular "switch" for activation or deactivation of certain functions provides new insight into the apparent multi-functionality of PrP(C).
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Affiliation(s)
- C. L. Haigh
- Department of Pathology, Melbourne Brain Centre, The University of Melbourne, Parkville, Melbourne, 3010 Australia
| | - A. R. McGlade
- Department of Pathology, Melbourne Brain Centre, The University of Melbourne, Parkville, Melbourne, 3010 Australia
- Mental Health Research Institute, The University of Melbourne, Parkville, Melbourne, 3010 Australia
| | - S. J. Collins
- Department of Pathology, Melbourne Brain Centre, The University of Melbourne, Parkville, Melbourne, 3010 Australia
- Florey Department of Neuroscience and Mental Health, The University of Melbourne, Melbourne, VIC 3010 Australia
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20
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Le Brun AP, Haigh CL, Drew SC, James M, Boland MP, Collins SJ. Neutron reflectometry studies define prion protein N-terminal peptide membrane binding. Biophys J 2014; 107:2313-24. [PMID: 25418300 PMCID: PMC4241452 DOI: 10.1016/j.bpj.2014.09.027] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 09/08/2014] [Accepted: 09/19/2014] [Indexed: 10/24/2022] Open
Abstract
The prion protein (PrP), widely recognized to misfold into the causative agent of the transmissible spongiform encephalopathies, has previously been shown to bind to lipid membranes with binding influenced by both membrane composition and pH. Aside from the misfolding events associated with prion pathogenesis, PrP can undergo various posttranslational modifications, including internal cleavage events. Alpha- and beta-cleavage of PrP produces two N-terminal fragments, N1 and N2, respectively, which interact specifically with negatively charged phospholipids at low pH. Our previous work probing N1 and N2 interactions with supported bilayers raised the possibility that the peptides could insert deeply with minimal disruption. In the current study we aimed to refine the binding parameters of these peptides with lipid bilayers. To this end, we used neutron reflectometry to define the structural details of this interaction in combination with quartz crystal microbalance interrogation. Neutron reflectometry confirmed that peptides equivalent to N1 and N2 insert into the interstitial space between the phospholipid headgroups but do not penetrate into the acyl tail region. In accord with our previous studies, interaction was stronger for the N1 fragment than for the N2, with more peptide bound per lipid. Neutron reflectometry analysis also detected lengthening of the lipid acyl tails, with a concurrent decrease in lipid area. This was most evident for the N1 peptide and suggests an induction of increased lipid order in the absence of phase transition. These observations stand in clear contrast to the findings of analogous studies of Ab and ?-synuclein and thereby support the possibility of a functional role for such N-terminal fragment-membrane interactions.
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Affiliation(s)
- Anton P Le Brun
- Bragg Institute, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, New South Wales, 2234, Australia
| | - Cathryn L Haigh
- Department of Pathology, Kenneth Myer Building, The University of Melbourne, Victoria, 3010, Australia
| | - Simon C Drew
- Florey Department of Neuroscience and Mental Health, The University of Melbourne, Victoria, 3010, Australia
| | - Michael James
- Bragg Institute, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, New South Wales, 2234, Australia; School of Chemistry, University of New South Wales, Kensington, New South Wales, 2052, Australia
| | - Martin P Boland
- Department of Pathology, Kenneth Myer Building, The University of Melbourne, Victoria, 3010, Australia
| | - Steven J Collins
- Department of Pathology, Kenneth Myer Building, The University of Melbourne, Victoria, 3010, Australia.
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21
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Hatty CR, Le Brun AP, Lake V, Clifton LA, Liu GJ, James M, Banati RB. Investigating the interactions of the 18kDa translocator protein and its ligand PK11195 in planar lipid bilayers. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1838:1019-30. [PMID: 24374318 DOI: 10.1016/j.bbamem.2013.12.013] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 12/16/2013] [Accepted: 12/18/2013] [Indexed: 12/20/2022]
Abstract
The functional effects of a drug ligand may be due not only to an interaction with its membrane protein target, but also with the surrounding lipid membrane. We have investigated the interaction of a drug ligand, PK11195, with its primary protein target, the integral membrane 18kDa translocator protein (TSPO), and model membranes using Langmuir monolayers, quartz crystal microbalance with dissipation monitoring (QCM-D) and neutron reflectometry (NR). We found that PK11195 is incorporated into lipid monolayers and lipid bilayers, causing a decrease in lipid area/molecule and an increase in lipid bilayer rigidity. NR revealed that PK11195 is incorporated into the lipid chain region at a volume fraction of ~10%. We reconstituted isolated mouse TSPO into a lipid bilayer and studied its interaction with PK11195 using QCM-D, which revealed a larger than expected frequency response and indicated a possible conformational change of the protein. NR measurements revealed a TSPO surface coverage of 23% when immobilised to a modified surface via its polyhistidine tag, and a thickness of 51Å for the TSPO layer. These techniques allowed us to probe both the interaction of TSPO with PK11195, and PK11195 with model membranes. It is possible that previously reported TSPO-independent effects of PK11195 are due to incorporation into the lipid bilayer and alteration of its physical properties. There are also implications for the variable binding profiles observed for TSPO ligands, as drug-membrane interactions may contribute to the apparent affinity of TSPO ligands.
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Affiliation(s)
- Claire R Hatty
- Medical Imaging & Radiation Sciences Faculty Research Group, Faculty of Health Sciences, The University of Sydney, c/o Brain & Mind Research Institute, 94 Mallett Street, Camperdown, NSW 2050, Australia
| | - Anton P Le Brun
- Bragg Institute, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - Vanessa Lake
- Bragg Institute, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - Luke A Clifton
- ISIS Pulsed Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Didcot OX11 0QX, UK
| | - Guo Jun Liu
- Medical Imaging & Radiation Sciences Faculty Research Group, Faculty of Health Sciences, The University of Sydney, c/o Brain & Mind Research Institute, 94 Mallett Street, Camperdown, NSW 2050, Australia; Life Sciences, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - Michael James
- Bragg Institute, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234, Australia; School of Chemistry, University of New South Wales, Kensington NSW 2052, Australia
| | - Richard B Banati
- Medical Imaging & Radiation Sciences Faculty Research Group, Faculty of Health Sciences, The University of Sydney, c/o Brain & Mind Research Institute, 94 Mallett Street, Camperdown, NSW 2050, Australia; Life Sciences, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234, Australia.
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22
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Targeted detection of phosphatidylserine in biomimetic membranes and in vitro cell systems using annexin V-containing cubosomes. Biomaterials 2013; 34:8361-9. [DOI: 10.1016/j.biomaterials.2013.07.042] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Accepted: 07/11/2013] [Indexed: 11/23/2022]
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23
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Zhou Z, Xiao G. Conformational conversion of prion protein in prion diseases. Acta Biochim Biophys Sin (Shanghai) 2013; 45:465-76. [PMID: 23580591 DOI: 10.1093/abbs/gmt027] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Prion diseases are a group of infectious fatal neurodegenerative diseases. The conformational conversion of a cellular prion protein (PrP(C)) into an abnormal misfolded isoform (PrP(Sc)) is the key event in prion diseases pathology. Under normal conditions, the high-energy barrier separates PrP(C) from PrP(Sc) isoform. However, pathogenic mutations, modifications as well as some cofactors, such as glycosaminoglycans, nucleic acids, and lipids, could modulate the conformational conversion process. Understanding the mechanism of conformational conversion of prion protein is essential for the biomedical research and the treatment of prion diseases. Particularly, the characterization of cofactors interacting with prion protein might provide new diagnostic and therapeutic strategies.
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Affiliation(s)
- Zheng Zhou
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
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24
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Fernandez DI, Le Brun AP, Whitwell TC, Sani MA, James M, Separovic F. The antimicrobial peptide aurein 1.2 disrupts model membranes via the carpet mechanism. Phys Chem Chem Phys 2012; 14:15739-51. [PMID: 23093307 DOI: 10.1039/c2cp43099a] [Citation(s) in RCA: 134] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The membrane interactions of the antimicrobial peptide aurein 1.2 were studied using a range of biophysical techniques to determine the location and the mechanism of action in DMPC (dimyristoylphosphatidylcholine) and DMPC/DMPG (dimyristoylphosphatidylglycerol) model membranes that mimic characteristics of eukaryotic and prokaryotic membranes, respectively. Neutron reflectometry and solid-state NMR revealed subtle changes in membrane structure caused by the peptide. Quartz crystal microbalance with dissipation, vesicle dye leakage and atomic force microscopy measurements were used to investigate the global mode of peptide interaction. Aurein 1.2 displayed an enhanced interaction with the anionic DMPC/DMPG membrane while exhibiting primarily a surface interaction with both types of model membranes, which led to bilayer disruption and membrane lysis. The antimicrobial peptide interaction is consistent with the carpet mechanism for aurein 1.2 with discrete structural changes depending on the type of phospholipid membrane.
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Affiliation(s)
- David I Fernandez
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, VIC 3010, Australia
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25
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Speight RE, Cooper MA. A Survey of the 2010 Quartz Crystal Microbalance Literature. J Mol Recognit 2012; 25:451-73. [DOI: 10.1002/jmr.2209] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Robert E. Speight
- Institute for Molecular Bioscience; The University of Queensland; St. Lucia; Brisbane; 4072; Australia
| | - Matthew A. Cooper
- Institute for Molecular Bioscience; The University of Queensland; St. Lucia; Brisbane; 4072; Australia
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26
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Microwave Synthesis of Prion Protein Fragments up to 111 Amino Acids in Length Generates Biologically Active Peptides. Int J Pept Res Ther 2011. [DOI: 10.1007/s10989-011-9275-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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27
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Turnbaugh JA, Westergard L, Unterberger U, Biasini E, Harris DA. The N-terminal, polybasic region is critical for prion protein neuroprotective activity. PLoS One 2011; 6:e25675. [PMID: 21980526 PMCID: PMC3183058 DOI: 10.1371/journal.pone.0025675] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Accepted: 09/09/2011] [Indexed: 11/19/2022] Open
Abstract
Several lines of evidence suggest that the normal form of the prion protein, PrP(C), exerts a neuroprotective activity against cellular stress or toxicity. One of the clearest examples of such activity is the ability of wild-type PrP(C) to suppress the spontaneous neurodegenerative phenotype of transgenic mice expressing a deleted form of PrP (Δ32-134, called F35). To define domains of PrP involved in its neuroprotective activity, we have analyzed the ability of several deletion mutants of PrP (Δ23-31, Δ23-111, and Δ23-134) to rescue the phenotype of Tg(F35) mice. Surprisingly, all of these mutants displayed greatly diminished rescue activity, although Δ23-31 PrP partially suppressed neuronal loss when expressed at very high levels. Our results pinpoint the N-terminal, polybasic domain as a critical determinant of PrP(C) neuroprotective activity, and suggest that identification of molecules interacting with this region will provide important clues regarding the normal function of the protein. Small molecule ligands targeting this region may also represent useful therapeutic agents for treatment of prion diseases.
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Affiliation(s)
- Jessie A. Turnbaugh
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts, United States of America
- Department of Cell Biology and Physiology Washington University School of Medicine St. Louis, St. Louis, Missouri, United States of America
| | - Laura Westergard
- Department of Cell Biology and Physiology Washington University School of Medicine St. Louis, St. Louis, Missouri, United States of America
| | - Ursula Unterberger
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - Emiliano Biasini
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - David A. Harris
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts, United States of America
- * E-mail:
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