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Pereira D, Santamaria A, Pawar N, Carrascosa-Tejedor J, Sardo M, Mafra L, Guzmán E, Owen DJ, Zaccai NR, Maestro A, Marín-Montesinos I. Engineering phosphatidylinositol-4,5-bisphosphate model membranes enriched in endocytic cargo: A neutron reflectometry, AFM and QCM-D structural study. Colloids Surf B Biointerfaces 2023; 227:113341. [PMID: 37210796 DOI: 10.1016/j.colsurfb.2023.113341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 05/05/2023] [Accepted: 05/09/2023] [Indexed: 05/23/2023]
Abstract
The combination of in vitro models of biological membranes based on solid-supported lipid bilayers (SLBs) and of surface sensitive techniques, such as neutron reflectometry (NR), atomic force microscopy (AFM) and quartz crystal microbalance with dissipation monitoring (QCM-D), is well suited to provide quantitative information about molecular level interactions and lipid spatial distributions. In this work, cellular plasma membranes have been mimicked by designing complex SLB, containing phosphatidylinositol 4,5-bisphosphate (PtdIns4,5P2) lipids as well as incorporating synthetic lipo-peptides that simulate the cytoplasmic tails of transmembrane proteins. The QCM-D results revealed that the adsorption and fusion kinetics of PtdIns4,5P2 are highly dependent of Mg2+. Additionally, it was shown that increasing concentrations of PtdIns4,5P2 leads to the formation of SLBs with higher homogeneity. The presence of PtdIns4,5P2 clusters was visualized by AFM. NR provided important insights about the structural organization of the various components within the SLB, highlighting that the leaflet symmetry of these SLBs is broken by the presence of CD4-derived cargo peptides. Finally, we foresee our study to be a starting point for more sophisticated in vitro models of biological membranes with the incorporation of inositol phospholipids and synthetic endocytic motifs.
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Affiliation(s)
- Daniel Pereira
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal; Large Scale Structures Group, Institut Laue-Langevin, 38042 Cedex 9, Grenoble, France
| | - Andreas Santamaria
- Large Scale Structures Group, Institut Laue-Langevin, 38042 Cedex 9, Grenoble, France; Departamento de Química Física, Universidad Complutense de Madrid, 28040, Madrid, Spain
| | - Nisha Pawar
- Centro de Fı́sica de Materiales (CSIC, UPV/EHU) - Materials Physics Center MPC, Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
| | - Javier Carrascosa-Tejedor
- Large Scale Structures Group, Institut Laue-Langevin, 38042 Cedex 9, Grenoble, France; Division of Pharmacy and Optometry, University of Manchester, M13 9PT Manchester, UK
| | - Mariana Sardo
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Luís Mafra
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Eduardo Guzmán
- Departamento de Química Física, Universidad Complutense de Madrid, 28040, Madrid, Spain; Instituto Pluridisciplinar, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - David J Owen
- Cambridge Institute for Medical Research, University of Cambridge, CB22 7QQ Cambridge, UK
| | - Nathan R Zaccai
- Cambridge Institute for Medical Research, University of Cambridge, CB22 7QQ Cambridge, UK
| | - Armando Maestro
- Centro de Fı́sica de Materiales (CSIC, UPV/EHU) - Materials Physics Center MPC, Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain; IKERBASQUE-Basque Foundation for Science, Plaza Euskadi 5, Bilbao 48009, Spain.
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2
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Santamaria A, Batchu KC, Fragneto G, Laux V, Haertlein M, Darwish TA, Russell RA, Zaccai NR, Guzmán E, Maestro A. Investigation on the relationship between lipid composition and structure in model membranes composed of extracted natural phospholipids. J Colloid Interface Sci 2023; 637:55-66. [PMID: 36682118 DOI: 10.1016/j.jcis.2023.01.043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 12/09/2022] [Accepted: 01/09/2023] [Indexed: 01/13/2023]
Abstract
HYPOTHESIS Unravelling the structural diversity of cellular membranes is a paramount challenge in life sciences. In particular, lipid composition affects the membrane collective behaviour, and its interactions with other biological molecules. EXPERIMENTS Here, the relationship between membrane composition and resultant structural features was investigated by surface pressure-area isotherms, Brewster angle microscopy and neutron reflectometry on in vitro membrane models of the mammalian plasma and endoplasmic-reticulum-Golgi intermediate compartment membranes in the form of Langmuir monolayers. Natural extracted yeast lipids were used because, unlike synthetic lipids, the acyl chain saturation pattern of yeast and mammalian lipids are similar. FINDINGS The structure of the model membranes, orthogonal to the plane of the membrane, as well as their lateral packing, were found to depend strongly on their specific composition, with cholesterol having a major influence on the in-plane morphology, yielding a coexistence of liquid-order and liquid-disorder phases.
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Affiliation(s)
- Andreas Santamaria
- Institut Laue-Langevin, 71 Avenue des Martyrs, 38042 Grenoble, Cedex 9, France; Departamento de Química Física, Universidad Complutense de Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain
| | - Krishna C Batchu
- Institut Laue-Langevin, 71 Avenue des Martyrs, 38042 Grenoble, Cedex 9, France
| | - Giovanna Fragneto
- Institut Laue-Langevin, 71 Avenue des Martyrs, 38042 Grenoble, Cedex 9, France; École doctorale de Physique, Université Grenoble Alpes, 38400 Saint-Martin-d'Héres, France
| | - Valérie Laux
- Institut Laue-Langevin, 71 Avenue des Martyrs, 38042 Grenoble, Cedex 9, France
| | - Michael Haertlein
- Institut Laue-Langevin, 71 Avenue des Martyrs, 38042 Grenoble, Cedex 9, France
| | - Tamim A Darwish
- National Deuteration Facility, Australian Nuclear Science and Technology Organisation, Lucas Heights 2232, NSW, Australia
| | - Robert A Russell
- National Deuteration Facility, Australian Nuclear Science and Technology Organisation, Lucas Heights 2232, NSW, Australia
| | - Nathan R Zaccai
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB22 7QQ, United Kingdom
| | - Eduardo Guzmán
- Departamento de Química Física, Universidad Complutense de Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain; Instituto Pluridisciplinar, Universidad Complutense de Madrid, Paseo Juan XXIII 1, 28040 Madrid, Spain
| | - Armando Maestro
- Centro de Fı́sica de Materiales (CSIC, UPV/EHU) - Materials Physics Center MPC, Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain; IKERBASQUE-Basque Foundation for Science, Plaza Euskadi 5, Bilbao 48009, Spain.
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3
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Koreny L, Mercado-Saavedra BN, Klinger CM, Barylyuk K, Butterworth S, Hirst J, Rivera-Cuevas Y, Zaccai NR, Holzer VJC, Klingl A, Dacks JB, Carruthers VB, Robinson MS, Gras S, Waller RF. Stable endocytic structures navigate the complex pellicle of apicomplexan parasites. Nat Commun 2023; 14:2167. [PMID: 37061511 PMCID: PMC10105704 DOI: 10.1038/s41467-023-37431-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 03/17/2023] [Indexed: 04/17/2023] Open
Abstract
Apicomplexan parasites have immense impacts on humanity, but their basic cellular processes are often poorly understood. Where endocytosis occurs in these cells, how conserved this process is with other eukaryotes, and what the functions of endocytosis are across this phylum are major unanswered questions. Using the apicomplexan model Toxoplasma, we identified the molecular composition and behavior of unusual, fixed endocytic structures. Here, stable complexes of endocytic proteins differ markedly from the dynamic assembly/disassembly of these machineries in other eukaryotes. We identify that these endocytic structures correspond to the 'micropore' that has been observed throughout the Apicomplexa. Moreover, conserved molecular adaptation of this structure is seen in apicomplexans including the kelch-domain protein K13 that is central to malarial drug-resistance. We determine that a dominant function of endocytosis in Toxoplasma is plasma membrane homeostasis, rather than parasite nutrition, and that these specialized endocytic structures originated early in infrakingdom Alveolata likely in response to the complex cell pellicle that defines this medically and ecologically important ancient eukaryotic lineage.
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Affiliation(s)
- Ludek Koreny
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1QW, UK
| | | | - Christen M Klinger
- Division of Infectious Diseases, Department of Medicine, University of Alberta, Edmonton, AB, T6G 2R3, Canada
| | | | - Simon Butterworth
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1QW, UK
| | - Jennifer Hirst
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, CB2 1QW, UK
| | - Yolanda Rivera-Cuevas
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Nathan R Zaccai
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, CB2 1QW, UK
| | - Victoria J C Holzer
- Plant Development, Ludwig-Maximilians-University Munich, Planegg-Martinsried, 82152, Germany
| | - Andreas Klingl
- Plant Development, Ludwig-Maximilians-University Munich, Planegg-Martinsried, 82152, Germany
| | - Joel B Dacks
- Division of Infectious Diseases, Department of Medicine, University of Alberta, Edmonton, AB, T6G 2R3, Canada
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, 370 05, Czech Republic
| | - Vern B Carruthers
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Margaret S Robinson
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, CB2 1QW, UK
| | - Simon Gras
- Experimental Parasitology, Department for Veterinary Sciences, Ludwig-Maximilians-University Munich, Planegg-Martinsried, 82152, Germany.
| | - Ross F Waller
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1QW, UK.
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Santamaria A, Carrascosa-Tejedor J, Guzmán E, Zaccai NR, Maestro A. Unravelling the orientation of the inositol-biphosphate ring and its dependence on phosphatidylinositol 4,5-bisphosphate cluster formation in model membranes. J Colloid Interface Sci 2023; 629:785-795. [PMID: 36195018 DOI: 10.1016/j.jcis.2022.09.095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 09/03/2022] [Accepted: 09/18/2022] [Indexed: 10/14/2022]
Abstract
HYPOTHESIS Inositol phospholipids are well known to form clusters in the cytoplasmic leaflet of the plasma membrane that are responsible for the interaction and recruitment of proteins involved in key biological processes like endocytosis, ion channel activation and secondary messenger production. Although their phosphorylated inositol ring headgroup plays an important role in protein binding, its orientation with respect to the plane of the membrane and its lateral packing density has not been previously described experimentally. EXPERIMENTS Here, we study phosphatidylinositol 4,5-bisphosphate (PIP2) planar model membranes in the form of Langmuir monolayers by surface pressure-area isotherms, Brewster angle microscopy and neutron reflectometry to elucidate the relation between lateral (in-plane) and perpendicular (out-of-plane) molecular organization of PIP2. FINDINGS Different surface areas were explored through monolayer compression, allowing us to correlate the formation of transient PIP2 clusters with the change in orientation of the inositol-biphosphate headgroup, which was experimentally determined by neutron reflectometry.
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Affiliation(s)
- Andreas Santamaria
- Large Scale Structures Group, Institut Laue-Langevin, 71 Avenue des Martyrs, 38042 Grenoble, Cedex 9, France; Departamento de Química-Física, Facultad de Ciencias Químicas, Universidad Complutense, Ciudad Universitaria s/n, 28040 Madrid, Spain
| | - Javier Carrascosa-Tejedor
- Large Scale Structures Group, Institut Laue-Langevin, 71 Avenue des Martyrs, 38042 Grenoble, Cedex 9, France; Division of Pharmacy and Optometry, University of Manchester, Manchester M13 9PT, United Kingdom
| | - Eduardo Guzmán
- Departamento de Química-Física, Facultad de Ciencias Químicas, Universidad Complutense, Ciudad Universitaria s/n, 28040 Madrid, Spain; Instituto Pluridisciplinar, Universidad Complutense de Madrid, Paseo Juan XXIII 1, 28040 Madrid, Spain.
| | - Nathan R Zaccai
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB22 7QQ, United Kingdom.
| | - Armando Maestro
- Centro de Fı́sica de Materiales (CSIC, UPV/EHU) - Materials Physics Center MPC, Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain; IKERBASQUE-Basque Foundation for Science, Plaza Euskadi 5, Bilbao 48009, Spain.
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5
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Zaccai NR, Kadlecova Z, Dickson VK, Korobchevskaya K, Kamenicky J, Kovtun O, Umasankar PK, Wrobel AG, Kaufman JGG, Gray SR, Qu K, Evans PR, Fritzsche M, Sroubek F, Höning S, Briggs JAG, Kelly BT, Owen DJ, Traub LM. FCHO controls AP2's initiating role in endocytosis through a PtdIns(4,5)P 2-dependent switch. Sci Adv 2022; 8:eabn2018. [PMID: 35486718 PMCID: PMC9054013 DOI: 10.1126/sciadv.abn2018] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 03/11/2022] [Indexed: 06/14/2023]
Abstract
Clathrin-mediated endocytosis (CME) is the main mechanism by which mammalian cells control their cell surface proteome. Proper operation of the pivotal CME cargo adaptor AP2 requires membrane-localized Fer/Cip4 homology domain-only proteins (FCHO). Here, live-cell enhanced total internal reflection fluorescence-structured illumination microscopy shows that FCHO marks sites of clathrin-coated pit (CCP) initiation, which mature into uniform-sized CCPs comprising a central patch of AP2 and clathrin corralled by an FCHO/Epidermal growth factor potential receptor substrate number 15 (Eps15) ring. We dissect the network of interactions between the FCHO interdomain linker and AP2, which concentrates, orients, tethers, and partially destabilizes closed AP2 at the plasma membrane. AP2's subsequent membrane deposition drives its opening, which triggers FCHO displacement through steric competition with phosphatidylinositol 4,5-bisphosphate, clathrin, cargo, and CME accessory factors. FCHO can now relocate toward a CCP's outer edge to engage and activate further AP2s to drive CCP growth/maturation.
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Affiliation(s)
- Nathan R. Zaccai
- CIMR, University of Cambridge, Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Zuzana Kadlecova
- CIMR, University of Cambridge, Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | | | - Kseniya Korobchevskaya
- Kennedy Institute of Rheumatology, University of Oxford, Roosevelt Drive, Oxford OX3 7FY, UK
| | - Jan Kamenicky
- Czech Academy of Sciences, Institute of Information Theory and Automation, Pod Vodarenskou vezi 4, 182 08 Prague 8, Czech Republic
| | - Oleksiy Kovtun
- MRC LMB Cambridge Biomedical Campus, Cambridge CB2 0QH, UK
| | - Perunthottathu K. Umasankar
- Intracellular Trafficking Laboratory, Transdisciplinary Biology Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, India
| | - Antoni G. Wrobel
- CIMR, University of Cambridge, Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | | | - Sally R. Gray
- CIMR, University of Cambridge, Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Kun Qu
- MRC LMB Cambridge Biomedical Campus, Cambridge CB2 0QH, UK
| | | | - Marco Fritzsche
- Kennedy Institute of Rheumatology, University of Oxford, Roosevelt Drive, Oxford OX3 7FY, UK
- Rosalind Franklin Institute, Harwell Campus, Didcot, UK
| | - Filip Sroubek
- Czech Academy of Sciences, Institute of Information Theory and Automation, Pod Vodarenskou vezi 4, 182 08 Prague 8, Czech Republic
| | - Stefan Höning
- Institute for Biochemistry I, Medical Faculty, University of Cologne, Joseph-Stelzmann-Straße 52, 50931 Cologne, Germany
| | - John A. G. Briggs
- MRC LMB Cambridge Biomedical Campus, Cambridge CB2 0QH, UK
- Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Bernard T. Kelly
- CIMR, University of Cambridge, Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - David J. Owen
- CIMR, University of Cambridge, Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Linton M. Traub
- Department of Cell Biology, University of Pittsburgh School of Medicine, 3500 Terrace Street, Pittsburgh, PA, USA
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6
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Santamaria A, Batchu KC, Matsarskaia O, Prévost SF, Russo D, Natali F, Seydel T, Hoffmann I, Laux V, Haertlein M, Darwish TA, Russell RA, Corucci G, Fragneto G, Maestro A, Zaccai NR. Strikingly Different Roles of SARS-CoV-2 Fusion Peptides Uncovered by Neutron Scattering. J Am Chem Soc 2022; 144:2968-2979. [PMID: 35157798 PMCID: PMC8862744 DOI: 10.1021/jacs.1c09856] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Indexed: 02/02/2023]
Abstract
Coronavirus disease-2019 (COVID-19), a potentially lethal respiratory illness caused by the coronavirus SARS-CoV-2, emerged in the end of 2019 and has since spread aggressively across the globe. A thorough understanding of the molecular mechanisms of cellular infection by coronaviruses is therefore of utmost importance. A critical stage in infection is the fusion between viral and host membranes. Here, we present a detailed investigation of the role of selected SARS-CoV-2 Spike fusion peptides, and the influence of calcium and cholesterol, in this fusion process. Structural information from specular neutron reflectometry and small angle neutron scattering, complemented by dynamics information from quasi-elastic and spin-echo neutron spectroscopy, revealed strikingly different functions encoded in the Spike fusion domain. Calcium drives the N-terminal of the Spike fusion domain to fully cross the host plasma membrane. Removing calcium, however, reorients the peptide back to the lipid leaflet closest to the virus, leading to significant changes in lipid fluidity and rigidity. In conjunction with other regions of the fusion domain, which are also positioned to bridge and dehydrate viral and host membranes, the molecular events leading to cell entry by SARS-CoV-2 are proposed.
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Affiliation(s)
- Andreas Santamaria
- Institut
Laue-Langevin, 38042 Grenoble, France
- Departamento
de Química Física, Universidad
Complutense de Madrid, 28040 Madrid, Spain
| | | | | | | | - Daniela Russo
- Institut
Laue-Langevin, 38042 Grenoble, France
- CNR-IOM
& INSIDE@ILL, 38042 Grenoble, France
| | - Francesca Natali
- Institut
Laue-Langevin, 38042 Grenoble, France
- CNR-IOM
& INSIDE@ILL, 38042 Grenoble, France
| | - Tilo Seydel
- Institut
Laue-Langevin, 38042 Grenoble, France
| | | | | | | | - Tamim A. Darwish
- National
Deuteration Facility, ANSTO-Sidney, Lucas Heights, NSW 2234, Australia
| | - Robert A. Russell
- National
Deuteration Facility, ANSTO-Sidney, Lucas Heights, NSW 2234, Australia
| | - Giacomo Corucci
- Institut
Laue-Langevin, 38042 Grenoble, France
- École
Doctorale de Physique, Université
Grenoble Alpes, 38400 Saint-Martin-d’Héres, France
| | - Giovanna Fragneto
- Institut
Laue-Langevin, 38042 Grenoble, France
- École
Doctorale de Physique, Université
Grenoble Alpes, 38400 Saint-Martin-d’Héres, France
| | - Armando Maestro
- Institut
Laue-Langevin, 38042 Grenoble, France
- Centro
de Física de Materiales (CSIC, UPV/EHU) − Materials
Physics Center MPC, Paseo
Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
- IKERBASQUE
− Basque Foundation for Science, Plaza Euskadi 5, E-48009 Bilbao, Spain
| | - Nathan R. Zaccai
- Cambridge
Institute for Medical Research, University
of Cambridge, Cambridge CB22 7QQ, United Kingdom
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7
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Crawley-Snowdon H, Yang JC, Zaccai NR, Davis LJ, Wartosch L, Herman EK, Bright NA, Swarbrick JS, Collins BM, Jackson LP, Seaman MNJ, Luzio JP, Dacks JB, Neuhaus D, Owen DJ. Mechanism and evolution of the Zn-fingernail required for interaction of VARP with VPS29. Nat Commun 2020; 11:5031. [PMID: 33024112 PMCID: PMC7539009 DOI: 10.1038/s41467-020-18773-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 09/08/2020] [Indexed: 01/13/2023] Open
Abstract
VARP and TBC1D5 are accessory/regulatory proteins of retromer-mediated retrograde trafficking from endosomes. Using an NMR/X-ray approach, we determined the structure of the complex between retromer subunit VPS29 and a 12 residue, four-cysteine/Zn++ microdomain, which we term a Zn-fingernail, two of which are present in VARP. Mutations that abolish VPS29:VARP binding inhibit trafficking from endosomes to the cell surface. We show that VARP and TBC1D5 bind the same site on VPS29 and can compete for binding VPS29 in vivo. The relative disposition of VPS29s in hetero-hexameric, membrane-attached, retromer arches indicates that VARP will prefer binding to assembled retromer coats through simultaneous binding of two VPS29s. The TBC1D5:VPS29 interaction is over one billion years old but the Zn-fingernail appears only in VARP homologues in the lineage directly giving rise to animals at which point the retromer/VARP/TBC1D5 regulatory network became fully established.
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Affiliation(s)
- Harriet Crawley-Snowdon
- MRC Laboratory of Molecular Biology Cambridge Biomedical Campus, Francis Crick Ave, Cambridge, CB2 0QH, UK
| | - Ji-Chun Yang
- MRC Laboratory of Molecular Biology Cambridge Biomedical Campus, Francis Crick Ave, Cambridge, CB2 0QH, UK
| | - Nathan R Zaccai
- CIMR, The Keith Peters Building, Hills Road, Cambridge, CB2 0QQ, UK
| | - Luther J Davis
- CIMR, The Keith Peters Building, Hills Road, Cambridge, CB2 0QQ, UK
| | - Lena Wartosch
- CIMR, The Keith Peters Building, Hills Road, Cambridge, CB2 0QQ, UK
| | - Emily K Herman
- Division of Infectious Disease, Department of Medicine, University of Alberta, Edmonton, Canada, T6G 2G3
| | | | - James S Swarbrick
- Pharmacology and Therapeutics, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Brett M Collins
- The University of Queensland, Institute for Molecular Bioscience, St Lucia, QLD, 4072, Australia
| | - Lauren P Jackson
- CIMR, The Keith Peters Building, Hills Road, Cambridge, CB2 0QQ, UK
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, 37232, USA
| | | | - J Paul Luzio
- CIMR, The Keith Peters Building, Hills Road, Cambridge, CB2 0QQ, UK.
| | - Joel B Dacks
- Division of Infectious Disease, Department of Medicine, University of Alberta, Edmonton, Canada, T6G 2G3.
| | - David Neuhaus
- MRC Laboratory of Molecular Biology Cambridge Biomedical Campus, Francis Crick Ave, Cambridge, CB2 0QH, UK.
| | - David J Owen
- CIMR, The Keith Peters Building, Hills Road, Cambridge, CB2 0QQ, UK.
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8
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Rhys GG, Wood CW, Beesley JL, Zaccai NR, Burton AJ, Brady RL, Thomson AR, Woolfson DN. Navigating the Structural Landscape of De Novo α-Helical Bundles. J Am Chem Soc 2019; 141:8787-8797. [PMID: 31066556 DOI: 10.1021/jacs.8b13354] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The association of amphipathic α helices in water leads to α-helical-bundle protein structures. However, the driving force for this-the hydrophobic effect-is not specific and does not define the number or the orientation of helices in the associated state. Rather, this is achieved through deeper sequence-to-structure relationships, which are increasingly being discerned. For example, for one structurally extreme but nevertheless ubiquitous class of bundle-the α-helical coiled coils-relationships have been established that discriminate between all-parallel dimers, trimers, and tetramers. Association states above this are known, as are antiparallel and mixed arrangements of the helices. However, these alternative states are less well understood. Here, we describe a synthetic-peptide system that switches between parallel hexamers and various up-down-up-down tetramers in response to single-amino-acid changes and solution conditions. The main accessible states of each peptide variant are characterized fully in solution and, in most cases, to high resolution with X-ray crystal structures. Analysis and inspection of these structures helps rationalize the different states formed. This navigation of the structural landscape of α-helical coiled coils above the dimers and trimers that dominate in nature has allowed us to design rationally a well-defined and hyperstable antiparallel coiled-coil tetramer (apCC-Tet). This robust de novo protein provides another scaffold for further structural and functional designs in protein engineering and synthetic biology.
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Affiliation(s)
- Guto G Rhys
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , United Kingdom
| | - Christopher W Wood
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , United Kingdom
| | - Joseph L Beesley
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , United Kingdom
| | - Nathan R Zaccai
- School of Biochemistry , University of Bristol , Medical Sciences Building, University Walk , Bristol BS8 1TD , United Kingdom
| | - Antony J Burton
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , United Kingdom
- Frick Chemistry Laboratory , Princeton University , Princeton , New Jersey 08544 , United States
| | - R Leo Brady
- School of Biochemistry , University of Bristol , Medical Sciences Building, University Walk , Bristol BS8 1TD , United Kingdom
| | - Andrew R Thomson
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , United Kingdom
- School of Chemistry , University of Glasgow , Glasgow G12 8QQ , United Kingdom
| | - Derek N Woolfson
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , United Kingdom
- School of Biochemistry , University of Bristol , Medical Sciences Building, University Walk , Bristol BS8 1TD , United Kingdom
- BrisSynBio , University of Bristol , Life Sciences Building, Tyndall Avenue , Bristol BS8 1TQ , United Kingdom
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9
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Navarro Negredo P, Edgar JR, Wrobel AG, Zaccai NR, Antrobus R, Owen DJ, Robinson MS. Contribution of the clathrin adaptor AP-1 subunit µ1 to acidic cluster protein sorting. J Cell Biol 2017; 216:2927-2943. [PMID: 28743825 PMCID: PMC5584140 DOI: 10.1083/jcb.201602058] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 04/19/2017] [Accepted: 07/07/2017] [Indexed: 11/22/2022] Open
Abstract
Acidic clusters act as sorting signals for packaging cargo into clathrin-coated vesicles (CCVs), and also facilitate down-regulation of MHC-I by HIV-1 Nef. To find acidic cluster sorting machinery, we performed a gene-trap screen and identified the medium subunit (µ1) of the clathrin adaptor AP-1 as a top hit. In µ1 knockout cells, intracellular CCVs still form, but acidic cluster proteins are depleted, although several other CCV components were either unaffected or increased, indicating that cells can compensate for long-term loss of AP-1. In vitro experiments showed that the basic patch on µ1 that interacts with the Nef acidic cluster also contributes to the binding of endogenous acidic cluster proteins. Surprisingly, µ1 mutant proteins lacking the basic patch and/or the tyrosine-based motif binding pocket could rescue the µ1 knockout phenotype completely. In contrast, these mutants failed to rescue Nef-induced down-regulation of MHC class I, suggesting a possible mechanism for attacking the virus while sparing the host cell.
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Affiliation(s)
- Paloma Navarro Negredo
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, England, UK
| | - James R Edgar
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, England, UK
| | - Antoni G Wrobel
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, England, UK
| | - Nathan R Zaccai
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, England, UK
| | - Robin Antrobus
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, England, UK
| | - David J Owen
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, England, UK
| | - Margaret S Robinson
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, England, UK
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10
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Baxter D, Perry SR, Hill TA, Kok WM, Zaccai NR, Brady RL, Fairlie DP, Mason JM. Downsizing Proto-oncogene cFos to Short Helix-Constrained Peptides That Bind Jun. ACS Chem Biol 2017. [PMID: 28636317 DOI: 10.1021/acschembio.7b00303] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The oncogenic transcription factor activator protein-1 (AP-1) is a DNA-binding protein that assembles through dimerization of Fos and Jun protein subunits, their leucine-rich helical sequences entwining into a coiled-coil structure. This study reports on downsizing the proto-oncogene cFos protein (380 residues) to shorter peptides (37-25 residues) modified with helix-inducing constraints to enhance binding to Jun. A crystal structure is reported for a 37-residue Fos-derived peptide (FosW) bound to Jun. This guided iterative downsizing of FosW to shorter peptide sequences that were constrained into stable water-soluble α-helices by connecting amino acid side chains to form cyclic pentapeptide components. Structural integrity in the presence and absence of Jun was assessed by circular dichroism spectroscopy, while the thermodynamics of binding to cFos was measured by isothermal titration calorimetry. A 25-residue constrained peptide, one-third shorter yet 25% more helical than the structurally characterized 37-residue Fos-derived peptide, retained 80% of the binding free energy as a result of preorganization in a Jun-binding helix conformation, with the entropy gain (TΔS = +3.2 kcal/mol) compensating for the enthalpy loss. Attaching a cell-penetrating peptide (TAT48-57) and a nuclear localization signal (SV40) promoted cell uptake, localization to the nucleus, and inhibition of the proliferation of two breast cancer cell lines.
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Affiliation(s)
- Daniel Baxter
- Department of Biology & Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K
| | - Samuel R. Perry
- Division
of Chemistry and Structural Biology, Australian Research Council Centre
of Excellence in Advanced Molecular Imaging, Institute for Molecular
Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Timothy A. Hill
- Division
of Chemistry and Structural Biology, Australian Research Council Centre
of Excellence in Advanced Molecular Imaging, Institute for Molecular
Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia
| | - W. Mei Kok
- Division
of Chemistry and Structural Biology, Australian Research Council Centre
of Excellence in Advanced Molecular Imaging, Institute for Molecular
Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Nathan R. Zaccai
- School
of Biochemistry, University of Bristol, University Walk, Bristol BS8 1TD, U.K
| | - R. Leo Brady
- School
of Biochemistry, University of Bristol, University Walk, Bristol BS8 1TD, U.K
| | - David P. Fairlie
- Division
of Chemistry and Structural Biology, Australian Research Council Centre
of Excellence in Advanced Molecular Imaging, Institute for Molecular
Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Jody M. Mason
- Department of Biology & Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K
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11
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Abstract
Biogenesis of the Gram-negative outer membrane involves the chaperone seventeen kilodalton protein (Skp). A Skp trimer is currently thought to bind its unfolded outer membrane protein (uOMP) substrates. Using sedimentation equilibrium, we discovered that Skp is not an obligate trimer under physiological conditions and that Na(+), Cl(-), Mg(2+), and PO4(3-) ions are not linked to Skp trimerization. These findings suggest that electrostatics play a negligible role in Skp assembly. Our results demonstrate that Skp monomers are populated at biologically relevant concentrations, which raises the idea that kinetic formation of Skp-uOMP complexes likely involves Skp monomer assembly around its substrate. In addition, van't Hoff analysis of Skp self-association does not support a previously proposed coupled folding and trimerization of Skp.
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Affiliation(s)
- Clifford W. Sandlin
- T.C. Jenkins Department of Biophysics, The Johns Hopkins University, Baltimore MD 21218
| | - Nathan R. Zaccai
- T.C. Jenkins Department of Biophysics, The Johns Hopkins University, Baltimore MD 21218
| | - Karen G. Fleming
- T.C. Jenkins Department of Biophysics, The Johns Hopkins University, Baltimore MD 21218
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12
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Burgess NC, Sharp TH, Thomas F, Wood CW, Thomson AR, Zaccai NR, Brady RL, Serpell LC, Woolfson DN. Modular Design of Self-Assembling Peptide-Based Nanotubes. J Am Chem Soc 2015. [DOI: 10.1021/jacs.5b03973] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Natasha C. Burgess
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
- Bristol Centre
for Functional Nanomaterials, University of Bristol, Tyndall Avenue, Bristol, BS8 1FD, United Kingdom
| | - Thomas H. Sharp
- Section
Electron Microscopy, Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Franziska Thomas
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
| | - Christopher W. Wood
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
- School
of Biochemistry, University of Bristol, Medical Sciences Building, University
Walk, Bristol, BS8 1TD, United Kingdom
| | - Andrew R. Thomson
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
| | - Nathan R. Zaccai
- School
of Biochemistry, University of Bristol, Medical Sciences Building, University
Walk, Bristol, BS8 1TD, United Kingdom
| | - R. Leo Brady
- School
of Biochemistry, University of Bristol, Medical Sciences Building, University
Walk, Bristol, BS8 1TD, United Kingdom
| | - Louise C. Serpell
- School
of Life Sciences, University of Sussex, Falmer, Brighton, East Sussex, BN1 9QG, United Kingdom
| | - Derek N. Woolfson
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
- School
of Biochemistry, University of Bristol, Medical Sciences Building, University
Walk, Bristol, BS8 1TD, United Kingdom
- BrisSynBio, University of Bristol, Life Sciences Building, Tyndall
Avenue, Bristol, BS8 1TQ, United Kingdom
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13
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Zaccai NR, Sandlin CW, Hoopes JT, Curtis JE, Fleming PJ, Fleming KG, Krueger S. Deuterium Labeling Together with Contrast Variation Small-Angle Neutron Scattering Suggests How Skp Captures and Releases Unfolded Outer Membrane Proteins. Methods Enzymol 2015; 566:159-210. [PMID: 26791979 PMCID: PMC4913355 DOI: 10.1016/bs.mie.2015.06.041] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
In Gram-negative bacteria, the chaperone protein Skp forms specific and stable complexes with membrane proteins while they are transported across the periplasm to the outer membrane. The jellyfish-like architecture of Skp is similar to the eukaryotic and archaeal prefoldins and the mitochondrial Tim chaperones, that is the α-helical "tentacles" extend from a β-strand "body" to create an internal cavity. Contrast variation small-angle neutron scattering (SANS) experiments on Skp alone in solution and bound in two different complexes to unfolded outer membrane proteins (uOMPs), OmpA and OmpW, demonstrate that the helical tentacles of Skp bind their substrate in a clamp-like mechanism in a conformation similar to that previously observed in the apo crystal structure of Skp. Deuteration of the uOMP component combined with contrast variation analysis allowed the shapes of Skp and uOMP as well as the location of uOMP with respect to Skp to be determined in both complexes. This represents unique information that could not be obtained without deuterium labeling of the uOMPs. The data yield the first direct structural evidence that the α-helical Skp tentacles move closer together on binding its substrate and that the structure of Skp is different when binding different uOMPs. This work presents, by example, a tutorial on performing SANS experiments using both deuterium labeling and contrast variation, including SANS theory, sample preparation, data collection, sample quality validation, data analysis, and structure modeling.
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Affiliation(s)
- Nathan R Zaccai
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland, USA
| | - Clifford W Sandlin
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland, USA
| | - James T Hoopes
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland, USA
| | - Joseph E Curtis
- National Institute of Standards and Technology, Gaithersburg, Maryland, USA
| | - Patrick J Fleming
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland, USA
| | - Karen G Fleming
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland, USA
| | - Susan Krueger
- National Institute of Standards and Technology, Gaithersburg, Maryland, USA.
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14
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Fletcher JM, Boyle AL, Bruning M, Bartlett GJ, Vincent TL, Zaccai NR, Armstrong CT, Bromley EHC, Booth PJ, Brady RL, Thomson AR, Woolfson DN. A basis set of de novo coiled-coil peptide oligomers for rational protein design and synthetic biology. ACS Synth Biol 2012; 1:240-50. [PMID: 23651206 DOI: 10.1021/sb300028q] [Citation(s) in RCA: 182] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Protein engineering, chemical biology, and synthetic biology would benefit from toolkits of peptide and protein components that could be exchanged reliably between systems while maintaining their structural and functional integrity. Ideally, such components should be highly defined and predictable in all respects of sequence, structure, stability, interactions, and function. To establish one such toolkit, here we present a basis set of de novo designed α-helical coiled-coil peptides that adopt defined and well-characterized parallel dimeric, trimeric, and tetrameric states. The designs are based on sequence-to-structure relationships both from the literature and analysis of a database of known coiled-coil X-ray crystal structures. These give foreground sequences to specify the targeted oligomer state. A key feature of the design process is that sequence positions outside of these sites are considered non-essential for structural specificity; as such, they are referred to as the background, are kept non-descript, and are available for mutation as required later. Synthetic peptides were characterized in solution by circular-dichroism spectroscopy and analytical ultracentrifugation, and their structures were determined by X-ray crystallography. Intriguingly, a hitherto widely used empirical rule-of-thumb for coiled-coil dimer specification does not hold in the designed system. However, the desired oligomeric state is achieved by database-informed redesign of that particular foreground and confirmed experimentally. We envisage that the basis set will be of use in directing and controlling protein assembly, with potential applications in chemical and synthetic biology. To help with such endeavors, we introduce Pcomp, an on-line registry of peptide components for protein-design and synthetic-biology applications.
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Affiliation(s)
- Jordan M. Fletcher
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8
1TS, U.K
| | - Aimee L. Boyle
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8
1TS, U.K
| | - Marc Bruning
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8
1TS, U.K
| | - Gail J. Bartlett
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8
1TS, U.K
| | - Thomas L. Vincent
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8
1TS, U.K
| | - Nathan R. Zaccai
- School of Biochemistry, University of Bristol, Medical Sciences Building, University
Walk, Bristol BS8 1TD, U.K
| | - Craig T. Armstrong
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8
1TS, U.K
- School of Biochemistry, University of Bristol, Medical Sciences Building, University
Walk, Bristol BS8 1TD, U.K
| | | | - Paula J. Booth
- School of Biochemistry, University of Bristol, Medical Sciences Building, University
Walk, Bristol BS8 1TD, U.K
| | - R. Leo Brady
- School of Biochemistry, University of Bristol, Medical Sciences Building, University
Walk, Bristol BS8 1TD, U.K
| | - Andrew R. Thomson
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8
1TS, U.K
| | - Derek N. Woolfson
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8
1TS, U.K
- School of Biochemistry, University of Bristol, Medical Sciences Building, University
Walk, Bristol BS8 1TD, U.K
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15
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Galfré E, Pitt SJ, Venturi E, Sitsapesan M, Zaccai NR, Tsaneva-Atanasova K, O'Neill S, Sitsapesan R. FKBP12 activates the cardiac ryanodine receptor Ca2+-release channel and is antagonised by FKBP12.6. PLoS One 2012; 7:e31956. [PMID: 22363773 PMCID: PMC3283708 DOI: 10.1371/journal.pone.0031956] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Accepted: 01/16/2012] [Indexed: 11/18/2022] Open
Abstract
Changes in FKBP12.6 binding to cardiac ryanodine receptors (RyR2) are implicated in mediating disturbances in Ca(2+)-homeostasis in heart failure but there is controversy over the functional effects of FKBP12.6 on RyR2 channel gating. We have therefore investigated the effects of FKBP12.6 and another structurally similar molecule, FKBP12, which is far more abundant in heart, on the gating of single sheep RyR2 channels incorporated into planar phospholipid bilayers and on spontaneous waves of Ca(2+)-induced Ca(2+)-release in rat isolated permeabilised cardiac cells. We demonstrate that FKBP12 is a high affinity activator of RyR2, sensitising the channel to cytosolic Ca(2+), whereas FKBP12.6 has very low efficacy, but can antagonise the effects of FKBP12. Mathematical modelling of the data shows the importance of the relative concentrations of FKBP12 and FKBP12.6 in determining RyR2 activity. Consistent with the single-channel results, physiological concentrations of FKBP12 (3 µM) increased Ca(2+)-wave frequency and decreased the SR Ca(2+)-content in cardiac cells. FKBP12.6, itself, had no effect on wave frequency but antagonised the effects of FKBP12.We provide a biophysical analysis of the mechanisms by which FK-binding proteins can regulate RyR2 single-channel gating. Our data indicate that FKBP12, in addition to FKBP12.6, may be important in regulating RyR2 function in the heart. In heart failure, it is possible that an alteration in the dual regulation of RyR2 by FKBP12 and FKBP12.6 may occur. This could contribute towards a higher RyR2 open probability, 'leaky' RyR2 channels and Ca(2+)-dependent arrhythmias.
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Affiliation(s)
- Elena Galfré
- School of Physiology & Pharmacology, Centre for Nanoscience and Quantum Information, and Bristol Heart Institute, University of Bristol, Bristol, United Kingdom
| | - Samantha J. Pitt
- School of Physiology & Pharmacology, Centre for Nanoscience and Quantum Information, and Bristol Heart Institute, University of Bristol, Bristol, United Kingdom
| | - Elisa Venturi
- School of Physiology & Pharmacology, Centre for Nanoscience and Quantum Information, and Bristol Heart Institute, University of Bristol, Bristol, United Kingdom
| | - Mano Sitsapesan
- School of Physiology & Pharmacology, Centre for Nanoscience and Quantum Information, and Bristol Heart Institute, University of Bristol, Bristol, United Kingdom
| | - Nathan R. Zaccai
- School of Physiology & Pharmacology, Centre for Nanoscience and Quantum Information, and Bristol Heart Institute, University of Bristol, Bristol, United Kingdom
| | | | - Stephen O'Neill
- Cardiovascular Research Group, Core Technology Facility, University of Manchester, Manchester, United Kingdom
| | - Rebecca Sitsapesan
- School of Physiology & Pharmacology, Centre for Nanoscience and Quantum Information, and Bristol Heart Institute, University of Bristol, Bristol, United Kingdom
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16
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Zaccai NR, Chi B, Thomson AR, Boyle AL, Bartlett GJ, Bruning M, Linden N, Sessions RB, Booth PJ, Brady RL, Woolfson DN. A de novo peptide hexamer with a mutable channel. Nat Chem Biol 2011; 7:935-41. [PMID: 22037471 PMCID: PMC3223406 DOI: 10.1038/nchembio.692] [Citation(s) in RCA: 149] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Accepted: 08/19/2011] [Indexed: 11/10/2022]
Abstract
The design of new proteins that expand the repertoire of natural protein structures represents a formidable challenge. Success in this area would increase understanding of protein structure, and present new scaffolds that could be exploited in biotechnology and synthetic biology. Here we describe the design, characterisation and X-ray crystal structure of a new coiled-coil protein. The de novo sequence forms a stand-alone, parallel, 6-helix bundle with a channel running through it. Although lined exclusively by hydrophobic leucine and isoleucine side chains, the 6 Å channel is permeable to water. One layer of leucine residues within the channel is mutable accepting polar aspartic acid (Asp) and histidine (His) side chains, and leading to subdivision and organization of solvent within the lumen. Moreover, these mutants can be combined to form a stable and unique (Asp-His)3 heterohexamer. These new structures provide a basis for engineering de novo proteins with new functions.
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17
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Agnew C, Borodina E, Zaccai NR, Conners R, Burton NM, Vicary JA, Cole DK, Antognozzi M, Virji M, Brady RL. Correlation of in situ mechanosensitive responses of the Moraxella catarrhalis adhesin UspA1 with fibronectin and receptor CEACAM1 binding. Proc Natl Acad Sci U S A 2011; 108:15174-8. [PMID: 21876142 PMCID: PMC3174611 DOI: 10.1073/pnas.1106341108] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bacterial cell surfaces are commonly decorated with a layer formed from multiple copies of adhesin proteins whose binding interactions initiate colonization and infection processes. In this study, we investigate the physical deformability of the UspA1 adhesin protein from Moraxella catarrhalis, a causative agent of middle-ear infections in humans. UspA1 binds a range of extracellular proteins including fibronectin, and the epithelial cellular receptor carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1). Electron microscopy indicates that unliganded UspA1 is densely packed at, and extends about 800 Å from, the Moraxella surface. Using a modified atomic force microscope, we show that the adhesive properties and thickness of the UspA1 layer at the cell surface varies on addition of either fibronectin or CEACAM1. This in situ analysis is then correlated with the molecular structure of UspA1. To provide an overall model for UspA1, we have determined crystal structures for two N-terminal fragments which are then combined with a previous structure of the CEACAM1-binding site. We show that the UspA1-fibronectin complex is formed between UspA1 head region and the 13th type-III domain of fibronectin and, using X-ray scattering, that the complex involves an angular association between these two proteins. In combination with a previous study, which showed that the CEACAM1-UspA1 complex is distinctively bent in solution, we correlate these observations on isolated fragments of UspA1 with its in situ response on the cell surface. This study therefore provides a rare direct demonstration of protein conformational change at the cell surface.
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Affiliation(s)
| | | | | | | | | | - James A. Vicary
- H. H. Wills Physics Laboratory and Nanoscience and Quantum Information Centre, University of Bristol, Bristol BS8 1TD, United Kingdom; and
| | - David K. Cole
- Department of Medical Biochemistry and Immunology, University of Cardiff, Cardiff CF14 4XN, United Kingdom
| | - Massimo Antognozzi
- H. H. Wills Physics Laboratory and Nanoscience and Quantum Information Centre, University of Bristol, Bristol BS8 1TD, United Kingdom; and
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18
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Hanslip SJ, Zaccai NR, Middelberg AP, Falconer RJ. Intrinsic fluorescence as an analytical probe of virus-like particle assembly and maturation. Biochem Biophys Res Commun 2008; 375:351-5. [DOI: 10.1016/j.bbrc.2008.08.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2008] [Accepted: 08/01/2008] [Indexed: 11/28/2022]
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19
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Stewart R, Song L, Carter SM, Sigalas C, Zaccai NR, Kanamarlapudi V, Bhat MB, Takeshima H, Sitsapesan R. Single-channel characterization of the rabbit recombinant RyR2 reveals a novel inactivation property of physiological concentrations of ATP. J Membr Biol 2008; 222:65-77. [PMID: 18418540 DOI: 10.1007/s00232-008-9102-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2008] [Accepted: 03/05/2008] [Indexed: 10/22/2022]
Abstract
Ryanodine receptor 2 (RyR2) cDNA has been available for more than 15 years; however, due to the complex nature of ligand gating in this channel, many aspects of recombinant RyR2 function have been unresearched. We established a stable, inducible HEK 293 cell line expressing full-length rabbit RyR2 cDNA and assessed the single-channel properties of the recombinant RyR2, with particular reference to ligand regulation with Ca2+ as the permeant ion. We found that the single-channel conductances of recombinant RyR2 and RyR2 isolated from cardiac muscle are essentially identical, as is irreversible modification by ryanodine. Although it is known that RyR2 expressed in HEK 293 cells is not associated with FKBP12.6, we demonstrate that these channels do not exhibit any discernable disorganized gating characteristics or subconductance states. We also show that the gating of recombinant RyR2 is indistinguishable from that of channels isolated from cardiac muscle when activated by cytosolic Ca2+, caffeine or suramin. The mechanisms underlying ATP activation are also similar; however, the experiments highlighted a novel effect of ATP at physiologically relevant concentrations of 5-10 mM. With Ca2+ as permeant ion, 5-10 mM ATP consistently inactivated recombinant channels (15/16 experiments). Such inactivation was rarely observed with native RyR2 isolated from cardiac muscle (1 in 16 experiments). However, if the channels were purified, inactivation by ATP was then revealed in all experiments. This action of ATP may be relevant for inactivation of sarcoplasmic reticulum Ca2+ release during cardiac excitation-contraction coupling or may represent unnatural behavior that is revealed when RyR2 is purified or expressed in noncardiac systems.
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Affiliation(s)
- Richard Stewart
- Department of Physiology and Pharmacology, School of Medical Sciences, University of Bristol, University Walk, Bristol, BS8 1TD, UK
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20
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Zaccai NR, Carter LG, Berrow NS, Sainsbury S, Nettleship JE, Walter TS, Harlos K, Owens RJ, Wilson KS, Stuart DI, Esnouf RM. Crystal structure of a 3-oxoacyl-(acylcarrier protein) reductase (BA3989) from Bacillus anthracis at 2.4-A resolution. Proteins 2008; 70:562-7. [PMID: 17894349 DOI: 10.1002/prot.21624] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Nathan R Zaccai
- The Oxford Protein Production Facility, Division of Structural Biology, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, United Kingdom
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21
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Zaccai NR, May AP, Robinson RC, Burtnick LD, Crocker PR, Brossmer R, Kelm S, Jones EY. Crystallographic and in Silico Analysis of the Sialoside-binding Characteristics of the Siglec Sialoadhesin. J Mol Biol 2007; 365:1469-79. [PMID: 17137591 DOI: 10.1016/j.jmb.2006.10.084] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2006] [Revised: 10/06/2006] [Accepted: 10/24/2006] [Indexed: 11/27/2022]
Abstract
The Siglec family of receptors mediates cell-surface interactions through recognition of sialylated glycoconjugates. Previously reported structures of the N-terminal domain of the Siglec sialoadhesin (SnD1) in complex with various sialic acid analogs revealed the structural template for sialic acid binding. To characterize further the carbohydrate-binding properties, we have determined the crystal structures of SnD1 in the absence of ligand, and in complex with 2-benzyl-Neu5NPro and 2-benzyl-Neu5NAc. These structures reveal that SnD1 undergoes very few structural changes on ligand binding and detail how two novel classes of sialic acid analogs bind, one of which unexpectedly can induce Siglec dimerization. In conjunction with in silico analysis, this set of structures informs us about the design of putative ligands with enhanced binding affinities and specificities to different Siglecs, and provides data with which to test the effectiveness of different computational drug design protocols.
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Affiliation(s)
- Nathan R Zaccai
- CR-UK Receptor Structure Research Group, Division of Structural Biology, The Henry Wellcome Building for Genomic Medicine, Roosevelt Drive, Headington, Oxford OX3 7BN, UK.
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22
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Zaccai NR, Yunus K, Matthews SM, Fisher AC, Falconer RJ. Refolding of a membrane protein in a microfluidics reactor. Eur Biophys J 2007; 36:581-8. [PMID: 17226042 DOI: 10.1007/s00249-006-0125-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2006] [Revised: 12/12/2006] [Accepted: 12/18/2006] [Indexed: 10/23/2022]
Abstract
Membrane protein production for structural studies is often hindered by the formation of non-specific aggregates from which the protein has to be denatured and then refolded to a functional state. We developed a new approach, which uses microfluidics channels, to refold protein correctly in quantities sufficient for structural studies. Green fluorescent protein (GFP), a soluble protein, and bacteriorhodopsin (BR), a transmembrane protein, were used to demonstrate the efficiency of the process. Urea-denatured GFP refolded as the urea diffused away from the protein, forming in the channel a uniform fluorescent band when observed by confocal microscopy. Sodium dodecyl sulphate-denatured BR refolded within the channel on mixing with detergent-lipid mixed micelles. The refolding, monitored by absorbance spectroscopy, was found to be flow rate dependent. This potential of microfluidic reactors for screening protein-folding conditions and producing protein would be particularly amenable for high-throughput applications required in structural genomics.
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Affiliation(s)
- Nathan R Zaccai
- Department of Pharmacology, University of Bristol, University Walk, Bristol, UK.
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23
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Hanslip SJ, Zaccai NR, Middelberg APJ, Falconer RJ. Assembly of Human Papillomavirus Type-16 Virus-Like Particles: Multifactorial Study of Assembly and Competing Aggregation. Biotechnol Prog 2006; 22:554-60. [PMID: 16599576 DOI: 10.1021/bp0502781] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Pentameric capsomeres of human papillomavirus capsid protein L1 expressed in Escherichia coli self-assemble into virus-like particles (VLPs) in vitro. A multifactorial experimental design was used to explore a wide range of solution conditions to optimize the assembly process. The degree of assembly was measured using an enzyme-linked immunosorbent assay, and a high-throughput turbidity assay was developed to monitor competing aggregation. The presence of zinc ions in the assembly buffer greatly increased the incidence of aggregation and had to be excluded from the experiment for meaningful analysis. Assembly of VLPs was optimal at a pH of about 6.5, calcium and sodium ions had no measurable effect, and dithiothreitol and glutathione inhibited assembly. Tryptophan fluorescence spectroscopy demonstrated that an increase in urea concentration reduced the rate of VLP formation but had no effect on the final concentration of assembled VLPs. This study demonstrates the use of the hanging-drop vapor-diffusion crystallization method to screen for conditions that promote aggregation and the use of tryptophan fluorescence spectroscopy for real-time monitoring of the assembly process.
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Affiliation(s)
- Simon J Hanslip
- Department of Chemical Engineering, University of Cambridge, Pembroke Street, Cambridge, CB2 3RA, UK
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24
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Batuwangala T, Shepherd D, Gadola SD, Gibson KJC, Zaccai NR, Fersht AR, Besra GS, Cerundolo V, Jones EY. The crystal structure of human CD1b with a bound bacterial glycolipid. J Immunol 2004; 172:2382-8. [PMID: 14764708 DOI: 10.4049/jimmunol.172.4.2382] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The human MHC class I-like molecule CD1b is distinctive among CD1 alleles in that it is capable of presenting a set of glycolipid species that show a very broad range of variation in the lengths of their acyl chains. A structure of CD1b complexed with relatively short acyl chain glycolipids plus detergent suggested how an interlinked network of channels within the Ag-binding groove could accommodate acyl chain lengths of up to 80 carbons. The structure of CD1b complexed with glucose monomycolate, reported in this study, confirms this hypothesis and illustrates how the distinctive substituents of intracellular bacterial glycolipids can be accommodated. The Ag-binding groove of CD1b is, uniquely among CD1 alleles, partitioned into channels suitable for the compact accommodation of lengthy acyl chains. The current crystal structure illustrates for the first time the binding of a natural bacterial lipid Ag to CD1b and shows how its novel structural features fit this molecule for its role in the immune response to intracellular bacteria.
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Affiliation(s)
- Thil Batuwangala
- Cancer Research UK Receptor Structure Group, The Division of Structural Biology, and Cancer Research UK
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25
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Gadola SD, Karadimitris A, Zaccai NR, Salio M, Dulphy N, Shepherd D, Jones EY, Cerundolo V. Generation of CD1 tetramers as a tool to monitor glycolipid-specific T cells. Philos Trans R Soc Lond B Biol Sci 2003; 358:875-7. [PMID: 12803920 PMCID: PMC1693178 DOI: 10.1098/rstb.2003.1267] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
CD1 molecules are beta(2)m-associated HLA class-I-like glycoproteins which have the unique ability to present glycolipid and phospholipid antigens to specific T lymphocytes. To study the biology of CD1 and its role in human disease we developed novel techniques for generation of recombinant CD1/lipid complexes by in vitro refolding. Fluorescent tetrameric complexes made from soluble recombinant CD1d/alpha-galactosylceramide complexes allowed highly sensitive and specific ex vivo and in vitro detection and functional characterization of novel human T-lymphocyte populations. Furthermore, protein crystals were obtained from soluble recombinant CD1b/beta(2)m-proteins loaded either with phosphatidylinositol or ganglioside GM2, which led to the first atomic structure determination of a CD1/lipid complex. The analysis of these crystal structures clarified how CD1b molecules can bind lipid ligands of different size, and revealed a broader spectrum of potential CD1b ligands than previously predicted.
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Affiliation(s)
- Stephan D Gadola
- Tumour Immunology Unit, The Weatherall Institute of Molecular Medicine, University of Oxford, UK
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26
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Zaccai NR, Maenaka K, Maenaka T, Crocker PR, Brossmer R, Kelm S, Jones EY. Structure-guided design of sialic acid-based Siglec inhibitors and crystallographic analysis in complex with sialoadhesin. Structure 2003; 11:557-67. [PMID: 12737821 DOI: 10.1016/s0969-2126(03)00073-x] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The Siglec family of receptors mediates cell surface interactions through recognition of sialylated glycoconjugates. The crystal structure of the N-terminal immunoglobulin-like domain of the Siglec sialoadhesin (SnD1) in complex with 2,3-sialyllactose has informed the design of sialic acid analogs (sialosides) that bind Siglecs with significantly enhanced affinities and specificities. Binding assays against sialoadhesin (Sn; Siglec-1), CD22 (Siglec-2), and MAG (Siglec-4) show a 10- to 300-fold reduction in IC(50) values (relative to methyl-alpha-Neu5Ac) for three sialosides bearing aromatic group modifications of the glycerol side chain: Me-alpha-9-N-benzoyl-amino-9-deoxy-Neu5Ac (BENZ), Me-alpha-9-N-(naphthyl-2-carbonyl)-amino-9-deoxy-Neu5Ac (NAP), and Me-alpha-9-N-(biphenyl-4-carbonyl)-amino-9-deoxy-Neu5Ac (BIP). Crystal structures of these sialosides in complex with SnD1 suggest explanations for the differences in specificity and affinity, providing further ideas for compound design of physiological and potentially therapeutic relevance.
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Affiliation(s)
- Nathan R Zaccai
- CR-UK Receptor Structure Research Group, Division of Structural Biology, The Henry Wellcome Building for Genomic Medicine, Roosevelt Drive, Headington, Oxford OX3 7BN, United Kingdom
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27
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Gadola SD, Zaccai NR, Harlos K, Shepherd D, Castro-Palomino JC, Ritter G, Schmidt RR, Jones EY, Cerundolo V. Structure of human CD1b with bound ligands at 2.3 A, a maze for alkyl chains. Nat Immunol 2002; 3:721-6. [PMID: 12118248 DOI: 10.1038/ni821] [Citation(s) in RCA: 193] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The human genome encodes five nonpolymorphic major histocompatibility complex class I-like glycoproteins, CD1a to CD1e, that present lipid antigens for specific recognition by T lymphocytes. Using single alkyl chain detergents, we developed a protocol to generate recombinant human CD1b-lipid complexes. We present here the crystal structures of CD1b in complex with either phosphatidylinositol or ganglioside GM2 at 2.3 A and 2.8 A resolutions, respectively. The antigen-binding groove houses four interlinked hydrophobic channels that are occupied by the alkyl chains of the glycolipid plus two detergent molecules. A distinct exit beneath the alpha 2 helix further contributes to the plasticity of the binding groove. These structures reveal the mechanism by which two alkyl chain lipids bind to CD1b, and how CD1b can adapt to ligands of different alkyl chain length. They also suggest how very long alkyl chains, such as those of mycolic acid, could be fully contained within the binding groove. These results extend the spectrum of potential CD1b ligands by revealing that, in addition to two alkyl chain lipids, mono-alkyl and triple-alkyl chain lipids can be accommodated in the binding groove.
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Affiliation(s)
- Stephan D Gadola
- Cancer Research UK Tumour Immunology Group, The Weatherall Institute of Molecular Medicine, Nuffield Department of Medicine, University of Oxford, Oxford OX3 9DS, UK. stephan.gadola@inselch
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28
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Maenaka K, Juji T, Nakayama T, Wyer JR, Gao GF, Maenaka T, Zaccai NR, Kikuchi A, Yabe T, Tokunaga K, Tadokoro K, Stuart DI, Jones EY, van der Merwe PA. Killer cell immunoglobulin receptors and T cell receptors bind peptide-major histocompatibility complex class I with distinct thermodynamic and kinetic properties. J Biol Chem 1999; 274:28329-34. [PMID: 10497191 DOI: 10.1074/jbc.274.40.28329] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Human natural killer cells and a subset of T cells express a repertoire of killer cell immunoglobulin receptors (KIRs) that recognize major histocompatibility complex (MHC) class I molecules. KIRs and T cell receptors (TCRs) bind in a peptide-dependent manner to overlapping regions of peptide-MHC class I complexes. KIRs with two immunoglobulin domains (KIR2Ds) recognize distinct subsets of HLA-C alleles. Here we use surface plasmon resonance to study the binding of soluble forms of KIR2DL1 and KIR2DL3 to several peptide-HLA-Cw7 complexes. KIR2DL3 bound to the HLA-Cw7 allele presenting the peptide RYRPGTVAL with a 1:1 stoichiometry and an affinity (K(d) approximately 7 microM at 25 degrees C) within the range of values measured for other cell-cell recognition molecules, including the TCR. Although KIR2DL1 is reported not to recognize the HLA-Cw7 allele in functional assays, it bound RYRPGTVAL/HLA-Cw7, albeit with a 10-20-fold lower affinity. TCR/peptide-MHC interactions are characterized by comparatively slow kinetics and unfavorable entropic changes (Willcox, B. E., Gao, G. F., Wyer, J. R. , Ladbury, J. E., Bell, J. I., Jakobsen, B. K., and van der Merwe, P. A. (1999) Immunity 10, 357-365), suggesting that binding is accompanied by conformational adjustments. In contrast, we show that KIR2DL3 binds RYRPGTVAL/HLA-Cw7 with fast kinetics and a favorable binding entropy, consistent with rigid body association. These results indicate that KIR/peptide-MHC class I interactions have properties typical of other cell-cell recognition molecules, and they highlight the unusual nature of TCR/peptide-MHC recognition.
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MESH Headings
- Amino Acid Sequence
- Base Sequence
- DNA Primers
- Histocompatibility Antigens Class I/metabolism
- Humans
- Killer Cells, Natural/immunology
- Kinetics
- Oligopeptides/metabolism
- Protein Binding
- Receptors, Antigen, T-Cell/chemistry
- Receptors, Antigen, T-Cell/metabolism
- Receptors, Immunologic/chemistry
- Receptors, Immunologic/metabolism
- Receptors, KIR
- Receptors, KIR2DL1
- Receptors, KIR2DL3
- Surface Plasmon Resonance
- Thermodynamics
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Affiliation(s)
- K Maenaka
- Structural Biology, Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Headington, Oxford OX3 7BN, United Kingdom.
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