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Čopič A, Antoine-Bally S, Giménez-Andrés M, La Torre Garay C, Antonny B, Manni MM, Pagnotta S, Guihot J, Jackson CL. A giant amphipathic helix from a perilipin that is adapted for coating lipid droplets. Nat Commun 2018; 9:1332. [PMID: 29626194 PMCID: PMC5889406 DOI: 10.1038/s41467-018-03717-8] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 03/05/2018] [Indexed: 11/21/2022] Open
Abstract
How proteins are targeted to lipid droplets (LDs) and distinguish the LD surface from the surfaces of other organelles is poorly understood, but many contain predicted amphipathic helices (AHs) that are involved in targeting. We have focused on human perilipin 4 (Plin4), which contains an AH that is exceptional in terms of length and repetitiveness. Using model cellular systems, we show that AH length, hydrophobicity, and charge are important for AH targeting to LDs and that these properties can compensate for one another, albeit at a loss of targeting specificity. Using synthetic lipids, we show that purified Plin4 AH binds poorly to lipid bilayers but strongly interacts with pure triglycerides, acting as a coat and forming small oil droplets. Because Plin4 overexpression alleviates LD instability under conditions where their coverage by phospholipids is limiting, we propose that the Plin4 AH replaces the LD lipid monolayer, for example during LD growth. Lipid droplets are cellular organelles important for cellular homeostasis and their disruption has been implicated in many diseases. Here the authors use a large amphipathic helix from perilipin 4 to uncover parameters important for specific lipid droplet targeting and stabilization of the oil core.
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Affiliation(s)
- Alenka Čopič
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013, Paris, France.
| | - Sandra Antoine-Bally
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013, Paris, France
| | - Manuel Giménez-Andrés
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013, Paris, France.,Université Paris-Sud, Université Paris-Saclay, 91405, Orsay, France
| | - César La Torre Garay
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013, Paris, France
| | - Bruno Antonny
- Université Côte d'Azur, CNRS, IPMC, 06560, Valbonne, France
| | - Marco M Manni
- Université Côte d'Azur, CNRS, IPMC, 06560, Valbonne, France
| | | | - Jeanne Guihot
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013, Paris, France
| | - Catherine L Jackson
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013, Paris, France
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2
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Ikeda K, Horiuchi A, Egawa A, Tamaki H, Fujiwara T, Nakano M. Nanodisc-to-Nanofiber Transition of Noncovalent Peptide-Phospholipid Assemblies. ACS OMEGA 2017; 2:2935-2944. [PMID: 31457628 PMCID: PMC6641012 DOI: 10.1021/acsomega.7b00424] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Accepted: 06/09/2017] [Indexed: 06/10/2023]
Abstract
We report a novel molecular architecture of peptide-phospholipid coassemblies. The amphiphilic peptide Ac-18A-NH2 (18A), which was designed to mimic apolipoprotein α-helices, has been shown to form nanodisc structures with phospholipid bilayers. We show that an 18A peptide cysteine substitution at residue 11, 18A[A11C], forms fibrous assemblies with 1-palmitoyl-2-oleoyl-phosphatidylcholine at a lipid-to-peptide (L/P) molar ratio of 1, a fiber diameter of 10-20 nm, and a length of more than 1 μm. Furthermore, 18A[A11C] can form nanodiscs with these lipid bilayers at L/P ratios of 4-6. The peptide adopts α-helical structures in both the nanodisc and nanofiber assemblies, although the α-helical bundle structures were evident only in the nanofibers, and the phospholipids of the nanofibers were not lamellar. Fluorescence spectroscopic analysis revealed that the peptide and lipid molecules in the nanofibers exhibited different solvent accessibility and hydrophobicity from those of the nanodiscs. Furthermore, the cysteine substitution at residue 11 did not result in disulfide bond formation, although it was responsible for the nanofiber formation, suggesting that this free sulfhydryl group has an important functional role. Alternatively, the disulfide dimer of 18A[A11C] preferentially formed nanodiscs, even at an L/P ratio of 1. Interconversions of these discoidal and fibrous assemblies were induced by the stepwise addition of free 18A[A11C] or liposomes into the solution. Furthermore, these structural transitions could also be induced by the introduction of oxidative and reductive stresses to the assemblies. Our results demonstrate that heteromolecular lipid-peptide complexes represent a novel approach to the construction of controllable and functional nanoscale assemblies.
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Affiliation(s)
- Keisuke Ikeda
- Graduate
School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
| | - Ayame Horiuchi
- Graduate
School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
| | - Ayako Egawa
- Institute
for Protein Research, Osaka University, 3-2 Yamadaoka, Suita 565-0871, Japan
| | - Hajime Tamaki
- Institute
for Protein Research, Osaka University, 3-2 Yamadaoka, Suita 565-0871, Japan
| | - Toshimichi Fujiwara
- Institute
for Protein Research, Osaka University, 3-2 Yamadaoka, Suita 565-0871, Japan
| | - Minoru Nakano
- Graduate
School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
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3
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Nakahara H. Fluidizing and Solidifying Effects of Perfluorooctylated Fatty Alcohols on Pulmonary Surfactant Monolayers. J Oleo Sci 2016; 65:99-109. [DOI: 10.5650/jos.ess15222] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Hiromichi Nakahara
- Department of Biophysical Chemistry, Graduate School of Pharmaceutical Sciences, Nagasaki International University
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4
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Bassereau P, Sorre B, Lévy A. Bending lipid membranes: experiments after W. Helfrich's model. Adv Colloid Interface Sci 2014; 208:47-57. [PMID: 24630341 DOI: 10.1016/j.cis.2014.02.002] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 02/02/2014] [Accepted: 02/03/2014] [Indexed: 10/25/2022]
Abstract
Current description of biomembrane mechanics originates for a large part from W. Helfrich's model. Based on his continuum theory, many experiments have been performed in the past four decades on simplified membranes in order to characterize the mechanical properties of lipid membranes and the contribution of polymers or proteins. The long-term goal was to develop a better understanding of the mechanical properties of cell membranes. In this paper, we will review representative experimental approaches that were developed during this period and the main results that were obtained.
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5
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Nakamura Y, Yukitake K, Nakahara H, Lee S, Shibata O, Lee S. Improvement of pulmonary surfactant activity by introducing D-amino acids into highly hydrophobic amphiphilic α-peptide Hel 13-5. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1838:2046-52. [PMID: 24796503 DOI: 10.1016/j.bbamem.2014.04.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 04/03/2014] [Accepted: 04/23/2014] [Indexed: 10/25/2022]
Abstract
The high costs of artificial pulmonary surfactants, ranging in hundreds per kilogram of body weight, used for treating the respiratory distress syndrome (RDS) premature babies have limited their applications. We have extensively studied soy lecithins and higher alcohols as lipid alternatives to expensive phospholipids such as DPPC and PG. As a substitute for the proteins, we have synthesized the peptide Hel 13-5D3 by introducing D-amino acids into a highly lipid-soluble, basic amphiphilic peptide, Hel 13-5, composed of 18 amino acid residues. Analysis of the surfactant activities of lipid-amphiphilic artificial peptide mixtures using lung-irrigated rat models revealed that a mixture (Murosurf SLPD3) of dehydrogenated soy lecithin, fractionated soy lecithin, palmitic acid (PA), and peptide Hel 13-5D3 (40:40:17.5:2.5, by weight) superior pulmonary surfactant activity than a commercially available pulmonary surfactant (beractant, Surfacten®). Experiments using ovalbumin-sensitized model animals revealed that the lipid-amphiphilic artificial peptide mixtures provided significant control over an increase in the pulmonary resistance induced by premature allergy reaction and reduced the number of acidocytes and neutrophils in lung-irrigated solution. The newly developed low-cost pulmonary surfactant system may be used for treatment of a wide variety of respiratory diseases.
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Affiliation(s)
| | - Ko Yukitake
- Fukuoka University Hospital, Fukuoka 814-0180, Japan
| | - Hiromichi Nakahara
- Department of Biophysical Chemistry, Faculty of Pharmaceutical Sciences, Nagasaki International University, Sasebo, Nagasaki 859-3298, Japan
| | - Sooyoung Lee
- Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University and Emergency & Critical Care Center, Kyushu University Hospital, Fukuoka 812-8582, Japan
| | - Osamu Shibata
- Department of Biophysical Chemistry, Faculty of Pharmaceutical Sciences, Nagasaki International University, Sasebo, Nagasaki 859-3298, Japan.
| | - Sannamu Lee
- Department of Biophysical Chemistry, Faculty of Pharmaceutical Sciences, Nagasaki International University, Sasebo, Nagasaki 859-3298, Japan; Department of Chemistry, Faculty of Science, Fukuoka University, Fukuoka 814-0180, Japan
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6
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Nakahara H, Lee S, Shibata O. Surface pressure induced structural transitions of an amphiphilic peptide in pulmonary surfactant systems by an in situ PM-IRRAS study. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:1205-13. [DOI: 10.1016/j.bbamem.2013.01.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 12/30/2012] [Accepted: 01/08/2013] [Indexed: 11/28/2022]
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7
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Nanostructured self assembled lipid materials for drug delivery and tissue engineering. Ther Deliv 2012; 2:1485-516. [PMID: 22826876 DOI: 10.4155/tde.11.105] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Every living organism comprises of lipids as basic building blocks in addition to other components. Utilizing these lipids for pharmaceutical and biomedical applications can overcome biocompatibility and biodegradability issues. A well known example is liposomes (lipids arranged in lamellar structures), but other than that there are additional unique mesophasic structures of lipids formed as a result of lipid polymorphisms, which include cubic-, hexagonal- or sponge-phase structures. These structures provide the advantages of stability and production feasibility compared with liposomes. Cubosomes, which exist in a cubic structure, have improved stability, bioadhesivity and biocompatibility. Hexagonal phases or hexosomes exhibit hexagonal arrangements and can encapsulate different drugs with high stability. Lipids also forms tube-like structures known as tubules and ribbons that are also utilized in different biomedical applications, especially in tissue engineering. Immune stimulating complexes are nanocage-like structures formed as a result of interactions of lipid, antigen and Quillaja saponin. These lipidic mesophasic structures have been utilized for gene, vaccine and drug delivery. This article addresses lipid self-assembled supramolecular nanostructures, including cubosomes, hexosomes, tubules, ribbons, cochleates, lipoplexes and immune stimulating complexes and their biomedical applications.
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8
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Nakahara H. A Study on Novel Artificial Lung Surfactants Incorporated with Partially Fluorinated Amphiphiles. YAKUGAKU ZASSHI 2012; 132:817-22. [DOI: 10.1248/yakushi.132.817] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Hiromichi Nakahara
- Department of Biophysical Chemistry, Faculty of Pharmaceutical Sciences, Nagasaki International University
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9
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Pandey AP, Haque F, Rochet JC, Hovis JS. α-Synuclein-induced tubule formation in lipid bilayers. J Phys Chem B 2011; 115:5886-93. [PMID: 21520980 DOI: 10.1021/jp1121917] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
α-Synuclein is a presynaptic protein that binds to phospholipid membranes and is involved in the pathogenesis of Parkinson's disease (PD). In this paper, we describe the effects of adding wild-type α-synuclein (WT) and three familial PD mutants (A53T, A30P, and E46K) to membranes containing 15-35 mol % anionic lipid. Tubules were observed to form in the membranes to an extent that depended on the α-synuclein variant, the anionic lipid content, and the protein concentration. For all four variants, tubule formation decreased with increasing anionic lipid content. Tubules were more readily observed with A30P and E46K than with WT or A53T. The results are consistent with a model wherein the helical content of α-synuclein increases with increasing anionic lipid content, and α-synuclein conformers with low helical content have a high propensity to induce tubule formation. This work, combined with previous work from our laboratory (Pandey et al. Biophys. J. 2009, 96, 540), shows that WT adsorption of the protein has deleterious effects on the membrane when the anionic lipid concentration is less than 30 mol % (tubule formation) or greater than 40 mol % (reorganization of the bilayer, clustering of protein).
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Affiliation(s)
- Anjan P Pandey
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA
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Nakahara H, Lee S, Krafft MP, Shibata O. Fluorocarbon-hybrid pulmonary surfactants for replacement therapy--a Langmuir monolayer study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:18256-18265. [PMID: 21049919 DOI: 10.1021/la103118d] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Effective additives to pulmonary surfactant (PS) preparations for therapy of respiratory distress syndrome (RDS) are being intensively sought. We report here the investigation of the effects of partially fluorinated amphiphiles (PFA) on the surface behavior of a model PS formulation. When small amounts of a partially fluorinated alcohol C(8)F(17)C(m)H(2m)OH (F8HmOH, m = 5 and 11) are added to the PS model preparation (a dipalmitoylphosphatidylcholine (DPPC)/Hel 13-5 peptide mixture) considered here, the effectiveness of the latter in in vitro pulmonary functions is enhanced. The mechanism for the improved efficacy depends on the hydrophobic chain length of the added PFA molecules. The shorter PFA, F8H5OH, when incorporated in the monolayer of the PS model preparation, promotes a disordered liquid-expanded (LE) phase upon lateral compression (fluidization). In contrast, the addition of the longer PFA, F8H11OH, reduces the disordered LE/ordered liquid-condensed (LC) phase transition pressure and promotes the growth of ordered domains (solidification). Furthermore, compression-expansion cycles suggest that F8H5OH, when incorporated in the PS model preparation, undergoes an irreversible elimination into the subphase, whereas F8H11OH enhances the squeeze-out phenomenon of the SP-B mimicking peptide, which is important in pulmonary functions and is related to the formation of a solid-like monolayer at the surface and of a surface reservoir just below the surface. F8H11OH particularly reinforces the effectiveness of DPPC in terms of minimum reachable surface tension, and of preservation of the integrated hysteresis area between compression and expansion isotherms, the two latter parameters being generally accepted indices for assessing PS efficacy. We suggest that PFA amphiphiles may be useful potential additives for synthetic PS preparations destined for treatment of RDS in premature infants and in adults.
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Affiliation(s)
- Hiromichi Nakahara
- Department of Biophysical Chemistry, Faculty of Pharmaceutical Sciences, Nagasaki International University, 2825-7 Huis Ten Bosch, Sasebo, Nagasaki 859-3298, Japan
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11
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Opaliński Ł, Kiel JAKW, Williams C, Veenhuis M, van der Klei IJ. Membrane curvature during peroxisome fission requires Pex11. EMBO J 2010; 30:5-16. [PMID: 21113128 PMCID: PMC3020119 DOI: 10.1038/emboj.2010.299] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Accepted: 11/03/2010] [Indexed: 01/25/2023] Open
Abstract
Pex11p is required for peroxisome proliferation. This study demonstrates that the N-terminus of Pex11p forms an amphipathic helix that generates membrane curvature required for peroxisome fission. Pex11 is a key player in peroxisome proliferation, but the molecular mechanisms of its function are still unknown. Here, we show that Pex11 contains a conserved sequence at the N-terminus that can adopt the structure of an amphipathic helix. Using Penicillium chrysogenum Pex11, we show that this amphipathic helix, termed Pex11-Amph, associates with liposomes in vitro. This interaction is especially evident when negatively charged liposomes are used with a phospholipid content resembling that of peroxisomal membranes. Binding of Pex11-Amph to negatively charged membrane vesicles resulted in strong tubulation. This tubulation of vesicles was also observed when the entire soluble N-terminal domain of Pex11 was used. Using mutant peptides, we demonstrate that maintaining the amphipathic properties of Pex11-Amph in conjunction with retaining its α-helical structure are crucial for its function. We show that the membrane remodelling capacity of the amphipathic helix in Pex11 is conserved from yeast to man. Finally, we demonstrate that mutations abolishing the membrane remodelling activity of the Pex11-Amph domain also hamper the function of full-length Pex11 in peroxisome fission in vivo.
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Affiliation(s)
- Łukasz Opaliński
- Molecular Cell Biology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Kluyver Centre for Genomics of Industrial Fermentation, Haren, The Netherlands
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12
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Nakahara H, Lee S, Shibata O. Specific interaction restrains structural transitions of an amphiphilic peptide in pulmonary surfactant model systems: An in situ PM-IRRAS investigation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1798:1263-71. [DOI: 10.1016/j.bbamem.2010.02.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2010] [Revised: 02/06/2010] [Accepted: 02/12/2010] [Indexed: 10/19/2022]
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13
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Drin G, Antonny B. Amphipathic helices and membrane curvature. FEBS Lett 2009; 584:1840-7. [PMID: 19837069 DOI: 10.1016/j.febslet.2009.10.022] [Citation(s) in RCA: 408] [Impact Index Per Article: 27.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Accepted: 10/09/2009] [Indexed: 01/29/2023]
Abstract
Numerous data have been collected on lipid-binding amphipathic helices involved in membrane-remodeling machineries and vesicular transport. Here we describe how, with regard to lipid composition, the physicochemical features of some amphipathic helices explain their ability to recognize membrane curvature or to participate in membrane remodeling. We propose that sensing highly-curved membranes requires that the polar and hydrophobic faces of the helix do not cooperate in lipid binding. A more detailed description of the interaction between amphipathic helices and lipids is however needed; notably to explain how new helices contribute to detection of modest changes in curvature or even negative curvature.
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Affiliation(s)
- Guillaume Drin
- Université de Nice-Sophia Antipolis and CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France.
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14
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Nakahara H, Lee S, Shibata O. Pulmonary surfactant model systems catch the specific interaction of an amphiphilic peptide with anionic phospholipid. Biophys J 2009; 96:1415-29. [PMID: 19217859 DOI: 10.1016/j.bpj.2008.11.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Accepted: 11/20/2008] [Indexed: 10/21/2022] Open
Abstract
Interfacial behavior was studied in pulmonary surfactant model systems containing an amphiphilic alpha-helical peptide (Hel 13-5), which consists of 13 hydrophobic and five hydrophilic amino acid residues. Fully saturated phospholipids of dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylglycerol (DPPG) were utilized to understand specific interactions between anionic DPPG and cationic Hel 13-5 for pulmonary functions. Surface pressure (pi)-molecular area (A) and surface potential (DeltaV)-A isotherms of DPPG/Hel 13-5 and DPPC/DPPG (4:1, mol/mol)/Hel 13-5 preparations were measured to obtain basic information on the phase behavior under compression and expansion processes. The interaction leads to a variation in squeeze-out surface pressures against a mole fraction of Hel 13-5, where Hel 13-5 is eliminated from the surface on compression. The phase behavior was visualized by means of Brewster angle microscopy, fluorescence microscopy, and atomic force microscopy. At low surface pressures, the formation of differently ordered domains in size and shape is induced by electrostatic interactions. The domains independently grow upon compression to high surface pressures, especially in the DPPG/Hel 13-5 system. Under the further compression process, protrusion masses are formed in AFM images in the vicinity of squeeze-out pressures. The protrusion masses, which are attributed to the squeezed-out Hel 13-5, grow larger in lateral size with increasing DPPG content in phospholipid compositions. During subsequent expansion up to 35 mN m(-1), the protrusions retain their height and lateral diameter for the DPPG/Hel 13-5 system, whereas the protrusions become smaller for the DPPC/Hel 13-5 and DPPC/DPPG/Hel 13-5 systems due to a reentrance of the ejected Hel 13-5 into the surface. In this work we detected for the first time, to our knowledge, a remarkably large hysteresis loop for cyclic DeltaV-A isotherms of the binary DPPG/Hel 13-5 preparation. This exciting phenomenon suggests that the specific interaction triggers two completely independent processes for Hel 13-5 during repeated compression and expansion: 1), squeezing-out into the subsolution; and 2), and close packing as a monolayer with DPPG at the interface. These characteristic processes are also strongly supported by atomic force microscopy observations. The data presented here provide complementary information on the mechanism and importance of the specific interaction between the phosphatidylglycerol headgroup and the polarized moiety of native surfactant protein B for biophysical functions of pulmonary surfactants.
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Affiliation(s)
- Hiromichi Nakahara
- Department of Biophysical Chemistry, Faculty of Pharmaceutical Sciences, Nagasaki International University, Nagasaki, Japan
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15
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Min CK, Bang SY, Cho BA, Choi YH, Yang JS, Lee SH, Seong SY, Kim KW, Kim S, Jung JU, Choi MS, Kim IS, Cho NH. Role of amphipathic helix of a herpesviral protein in membrane deformation and T cell receptor downregulation. PLoS Pathog 2008; 4:e1000209. [PMID: 19023411 PMCID: PMC2581436 DOI: 10.1371/journal.ppat.1000209] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2008] [Accepted: 10/16/2008] [Indexed: 11/18/2022] Open
Abstract
Lipid rafts are membrane microdomains that function as platforms for signal transduction and membrane trafficking. Tyrosine kinase interacting protein (Tip) of T lymphotropic Herpesvirus saimiri (HVS) is targeted to lipid rafts in T cells and downregulates TCR and CD4 surface expression. Here, we report that the membrane-proximal amphipathic helix preceding Tip's transmembrane (TM) domain mediates lipid raft localization and membrane deformation. In turn, this motif directs Tip's lysosomal trafficking and selective TCR downregulation. The amphipathic helix binds to the negatively charged lipids and induces liposome tubulation, the TM domain mediates oligomerization, and cooperation of the membrane-proximal helix with the TM domain is sufficient for localization to lipid rafts and lysosomal compartments, especially the mutivesicular bodies. These findings suggest that the membrane-proximal amphipathic helix and TM domain provide HVS Tip with the unique ability to deform the cellular membranes in lipid rafts and to downregulate TCRs potentially through MVB formation.
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Affiliation(s)
- Chan-Ki Min
- Department of Microbiology and Immunology, College of Medicine and Institute of Endemic Diseases, Seoul National University Medical Research Center and Bundang Hospital, Seoul, Korea
| | - Sun-Young Bang
- Department of Microbiology and Immunology, College of Medicine and Institute of Endemic Diseases, Seoul National University Medical Research Center and Bundang Hospital, Seoul, Korea
| | - Bon-A Cho
- Department of Microbiology and Immunology, College of Medicine and Institute of Endemic Diseases, Seoul National University Medical Research Center and Bundang Hospital, Seoul, Korea
| | - Yun-Hui Choi
- Department of Microbiology and Immunology, College of Medicine and Institute of Endemic Diseases, Seoul National University Medical Research Center and Bundang Hospital, Seoul, Korea
| | - Jae-Seong Yang
- Department of Life Science and School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang, Kyungbuk, Korea
| | - Sun-Hwa Lee
- Seoul National University Hospital, Innovative Research Institute for Cell Therapy, Chongno-Gu, Seoul, Korea
| | - Seung-Yong Seong
- Department of Microbiology and Immunology, College of Medicine and Institute of Endemic Diseases, Seoul National University Medical Research Center and Bundang Hospital, Seoul, Korea
- Seoul National University Hospital, Innovative Research Institute for Cell Therapy, Chongno-Gu, Seoul, Korea
| | - Ki Woo Kim
- National Instrumentation Center for Environmental Management, Seoul National University, Gwanak-Gu, Seoul, Korea
| | - Sanguk Kim
- Department of Life Science and School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang, Kyungbuk, Korea
| | - Jae Ung Jung
- Department of Molecular Microbiology and Immunology, University of Southern California School of Medicine, Los Angeles, California, United States of America
| | - Myung-Sik Choi
- Department of Microbiology and Immunology, College of Medicine and Institute of Endemic Diseases, Seoul National University Medical Research Center and Bundang Hospital, Seoul, Korea
| | - Ik-Sang Kim
- Department of Microbiology and Immunology, College of Medicine and Institute of Endemic Diseases, Seoul National University Medical Research Center and Bundang Hospital, Seoul, Korea
| | - Nam-Hyuk Cho
- Department of Microbiology and Immunology, College of Medicine and Institute of Endemic Diseases, Seoul National University Medical Research Center and Bundang Hospital, Seoul, Korea
- * E-mail:
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16
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Wang C, Yin S, Chen S, Xu H, Wang Z, Zhang X. Controlled Self-Assembly Manipulated by Charge-Transfer Interactions: From Tubes to Vesicles. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200803361] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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17
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Wang C, Yin S, Chen S, Xu H, Wang Z, Zhang X. Controlled Self-Assembly Manipulated by Charge-Transfer Interactions: From Tubes to Vesicles. Angew Chem Int Ed Engl 2008; 47:9049-52. [DOI: 10.1002/anie.200803361] [Citation(s) in RCA: 188] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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18
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Zemel A, Ben-Shaul A, May S. Modulation of the Spontaneous Curvature and Bending Rigidity of Lipid Membranes by Interfacially Adsorbed Amphipathic Peptides. J Phys Chem B 2008; 112:6988-96. [DOI: 10.1021/jp711107y] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Assaf Zemel
- Department of Physical Chemistry and the Fritz Haber Research Center, The Hebrew University, Jerusalem 91904, Israel,
- Department of Physics, North Dakota State University, Fargo, North Dakota 58105-5566
| | - Avinoam Ben-Shaul
- Department of Physical Chemistry and the Fritz Haber Research Center, The Hebrew University, Jerusalem 91904, Israel,
- Department of Physics, North Dakota State University, Fargo, North Dakota 58105-5566
| | - Sylvio May
- Department of Physical Chemistry and the Fritz Haber Research Center, The Hebrew University, Jerusalem 91904, Israel,
- Department of Physics, North Dakota State University, Fargo, North Dakota 58105-5566
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19
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Factors influencing local membrane curvature induction by N-BAR domains as revealed by molecular dynamics simulations. Biophys J 2008; 95:1866-76. [PMID: 18469070 DOI: 10.1529/biophysj.107.121160] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
N-BAR domains are protein modules that bind to and induce curvature in membranes via a charged concave surface and N-terminal amphipathic helices. Recently, molecular dynamics simulations have demonstrated that the N-BAR domain can induce a strong local curvature that matches the curvature of the BAR domain surface facing the bilayer. Here we present further molecular dynamics simulations that examine in greater detail the roles of the concave surface and amphipathic helices in driving local membrane curvature. We find that the strong curvature induction observed in our previous simulations requires the stable presentation of the charged concave surface to the membrane and is not driven by the membrane-embedded amphipathic helices. Nevertheless, without these amphipathic helices embedded in the membrane, the N-BAR domain does not maintain a close association with the bilayer, and fails to drive membrane curvature. Increasing the membrane negative charge through the addition of PIP(2) facilitates closer association with the membrane in the absence of embedded helices. At sufficiently high concentrations, amphipathic helices embedded in the membrane drive membrane curvature independently of the BAR domain.
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20
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Agrawal P, Kiihne S, Hollander J, Hulsbergen F, Hofmann M, Langosch D, de Groot H. Solid state NMR investigation of the interaction between biomimetic lipid bilayers and de novo designed fusogenic peptides. Chembiochem 2007; 8:493-6. [PMID: 17328022 DOI: 10.1002/cbic.200600518] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Prashant Agrawal
- Biophysical Organic Chemistry/Solid State NMR, Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands
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21
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Dikeakos JD, Lacombe MJ, Mercure C, Mireuta M, Reudelhuber TL. A hydrophobic patch in a charged alpha-helix is sufficient to target proteins to dense core secretory granules. J Biol Chem 2006; 282:1136-43. [PMID: 17092937 DOI: 10.1074/jbc.m605718200] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Many endocrine and neuroendocrine cells contain specialized secretory organelles called dense core secretory granules. These organelles are the repository of proteins and peptides that are secreted in a regulated manner when the cell receives a physiological stimulus. The targeting of proteins to these secretory granules is crucial for the generation of certain peptide hormones, including insulin and ACTH. Although previous work has demonstrated that proteins destined to a variety of cellular locations, including secretory granules, contain targeting sequences, no single consensus sequence for secretory granule-sorting signals has emerged. We have shown previously that alpha-helical domains in the C-terminal tail of the prohormone convertase PC1/3 play an important role in the ability of this region of the protein to direct secretory granule targeting (Jutras, I. Seidah, N. G., and Reudelhuber, T. L. (2000) J. Biol. Chem. 275, 40337-40343). In this study, we show that a variety of alpha-helical domains are capable of directing a heterologous secretory protein to granules. By testing a series of synthetic alpha-helices, we also demonstrate that the presence of charged (either positive or negative) amino acids spatially segregated from a hydrophobic patch in the alpha-helices of secretory proteins likely plays a critical role in the ability of these structures to direct secretory granule sorting.
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Affiliation(s)
- Jimmy D Dikeakos
- Laboratory of Molecular Biochemistry of Hypertension, Clinical Research Institute of Montreal, Montreal, Quebec H2W 1R7, Canada
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22
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Domanov YA, Kinnunen PKJ. Antimicrobial peptides temporins B and L induce formation of tubular lipid protrusions from supported phospholipid bilayers. Biophys J 2006; 91:4427-39. [PMID: 16997872 PMCID: PMC1779916 DOI: 10.1529/biophysj.106.091702] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The binding of the antimicrobial peptides temporins B and L to supported lipid bilayer (SLB) model membranes composed of phosphatidylcholine and phosphatidylglycerol (4:1, mol/mol) caused the formation of fibrillar protrusions, visible by fluorescent microscopy of both a fluorescent lipid analog and a labeled peptide. Multicolor imaging at low peptide-to-lipid ratios (P/L < approximately 1:5) revealed an initial in-plane segregation of membrane-bound peptide and partial exclusion of lipid from the peptide-enriched areas. Subsequently, at higher P/L numerous flexible lipid fibrils were seen growing from the areas enriched in lipid. The fibrils have diameters <250 nm and lengths of up to approximately 1 mm. Fibril formation reduces the in-plane heterogeneity and results in a relatively even redistribution of bound peptide over the planar bilayer and the fibrils. Physical properties of the lipid fibrils suggest that they have a tubular structure. Our data demonstrate that the peptide-lipid interactions alone can provide a driving force for the spontaneous membrane shape transformations leading to tubule outgrowth and elongation. Further experiments revealed the importance of positive curvature strain in the tubulation process as well as the sufficient positive charge on the peptide (>/=+2). The observed membrane transformations could provide a simplified in vitro model for morphogenesis of intracellular tubular structures and intercellular connections.
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Affiliation(s)
- Yegor A Domanov
- Helsinki Biophysics & Biomembrane Group, Medical Biochemistry/Institute of Biomedicine, University of Helsinki, Helsinki, Finland
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23
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Inouye H, Sharma D, Goux WJ, Kirschner DA. Structure of core domain of fibril-forming PHF/Tau fragments. Biophys J 2006; 90:1774-89. [PMID: 16339876 PMCID: PMC1367326 DOI: 10.1529/biophysj.105.070136] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2005] [Accepted: 11/14/2005] [Indexed: 12/21/2022] Open
Abstract
Short peptide sequences within the microtubule binding domain of the protein Tau are proposed to be core nucleation sites for formation of amyloid fibrils displaying the paired helical filament (PHF) morphology characteristic of neurofibrillary tangles. To study the structure of these proposed nucleation sites, we analyzed the x-ray diffraction patterns from the assemblies formed by a variety of PHF/tau-related peptide constructs containing the motifs VQIINK (PHF6*) in the second repeat and VQIVYK (PHF6) in the third repeat of tau. Peptides included: tripeptide acetyl-VYK-amide (AcVYK), tetrapeptide acetyl-IVYK-amide (AcPHF4), hexapeptide acetyl-VQIVYK-amide (AcPHF6), and acetyl-GKVQIINKLDLSNVQKDNIKHGSVQIVYKPVDLSKVT-amide (AcTR4). All diffraction patterns showed reflections at spacings of 4.7 A, 3.8 A, and approximately 8-10 A, which are characteristic of an orthogonal unit cell of beta-sheets having dimensions a=9.4 A, b=6.6 A, and c=approximately 8-10 A (where a, b, and c are the lattice constants in the H-bonding, chain, and intersheet directions). The sharp 4.7 A reflections indicate that the beta-crystallites are likely to be elongated along the H-bonding direction and in a cross-beta conformation. The assembly of the AcTR4 peptide, which contains both the PHF6 and PHF6* motifs, consisted of twisted sheets, as indicated by a unique fanning of the diffuse equatorial scattering and meridional accentuation of the (210) reflection at 3.8 A spacing. The diffraction data for AcVYK, AcPHF4, and AcPHF6 all were consistent with approximately 50 A-wide tubular assemblies having double-walls, where beta-strands constitute the walls. In this structure, the peptides are H-bonded together in the fiber direction, and the intersheet direction is radial. The positive-charged lysine residues face the aqueous medium, and tyrosine-tyrosine aromatic interactions stabilize the intersheet (double-wall) layers. This particular contact, which may be involved in PHF fibril formation, is proposed here as a possible aromatic target for anti-tauopathy drugs.
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Affiliation(s)
- Hideyo Inouye
- Boston College, Biology Department, Chestnut Hill, Massachusetts, USA
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24
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Abstract
Membrane curvature is no longer seen as a passive consequence of cellular activity but an active means to create membrane domains and to organize centres for membrane trafficking. Curvature can be dynamically modulated by changes in lipid composition, the oligomerization of curvature scaffolding proteins and the reversible insertion of protein regions that act like wedges in membranes. There is an interplay between curvature-generating and curvature-sensing proteins during vesicle budding. This is seen during vesicle budding and in the formation of microenvironments. On a larger scale, membrane curvature is a prime player in growth, division and movement.
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Affiliation(s)
- Harvey T McMahon
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK.
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25
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Nakahara H, Nakamura S, Lee S, Sugihara G, Shibata O. Influence of a new amphiphilic peptide with phospholipid monolayers at the air–water interface. Colloids Surf A Physicochem Eng Asp 2005. [DOI: 10.1016/j.colsurfa.2005.05.036] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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26
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Shimizu T, Masuda M, Minamikawa H. Supramolecular Nanotube Architectures Based on Amphiphilic Molecules. Chem Rev 2005; 105:1401-43. [PMID: 15826016 DOI: 10.1021/cr030072j] [Citation(s) in RCA: 1326] [Impact Index Per Article: 69.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Toshimi Shimizu
- Nanoarchitectonics Research Center, National Institute of Advanced Industrial Science and Technology, Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
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27
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KUWAHARA J, AKISADA H, WAKAYAMA N, KATO T, NISHINO N. Amyloid Fibril Formation of a Simple Decapeptide in a Micellar Environment. J Oleo Sci 2005. [DOI: 10.5650/jos.54.225] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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28
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Tashima Y, Oe R, Lee S, Sugihara G, Chambers EJ, Takahashi M, Yamada T. The effect of cholesterol and monosialoganglioside (GM1) on the release and aggregation of amyloid beta-peptide from liposomes prepared from brain membrane-like lipids. J Biol Chem 2004; 279:17587-95. [PMID: 14709559 DOI: 10.1074/jbc.m308622200] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In order to investigate the influence of cholesterol (Ch) and monosialoganglioside (GM1) on the release and subsequent deposition/aggregation of amyloid beta peptide (Abeta)-(1-40) and Abeta-(1-42), we have examined Abeta peptide model membrane interactions by circular dichroism, turbidity measurements, and transmission electron microscopy (TEM). Model liposomes containing Abeta peptide and a lipid mixture composition similar to that found in the cerebral cortex membranes (CCM-lipid) have been prepared. In all, four Abeta-containing liposomes were investigated: CCM-lipid; liposomes with no GM1 (GM1-free lipid); those with no cholesterol (Ch-free lipid); liposomes with neither cholesterol nor GM1 (Ch-GM1-free lipid). In CCM liposomes, Abeta was rapidly released from membranes to form a well defined fibril structure. However, for the GM1-free lipid, Abeta was first released to yield a fibril structure about the membrane surface, then the membrane became disrupted resulting in the formation of small vesicles. In Ch-free lipid, a fibril structure with a phospholipid membrane-like shadow formed, but this differed from the well defined fibril structure seen for CCM-lipid. In Ch-GM1-free lipid, no fibril structure formed, possibly because of membrane solubilization by Abeta. The absence of fibril structure was noted at physiological extracellular pH (7.4) and also at liposomal/endosomal pH (5.5). Our results suggest a possible role for both Ch and GM1 in the membrane release of Abeta from brain lipid bilayers.
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Affiliation(s)
- Yoshihiko Tashima
- Department of Chemistry, Faculty of Science, Fukuoka University, Fukuoka 814-0180, Japan
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29
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Abstract
Membrane traffic requires the generation of high-curvature lipid-bound transport carriers represented by tubules and vesicles. The mechanisms through which membranes are deformed has gained much recent attention. A major advance has been the demonstration that direct interactions between cytosolic proteins and lipid bilayers are important in the acquisition of membrane curvature. Rather than being driven only by the formation of membrane-associated structural scaffolds, membrane deformation requires physical perturbation of the lipid bilayer. A variety of proteins have been identified that directly bind and deform membranes. An emerging theme in this process is the importance of amphipathic peptides that partially penetrate the lipid bilayer.
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Affiliation(s)
- Khashayar Farsad
- Department of Cell Biology, Howard Hughes Medical Institute, Boyer Center for Molecular Medicine, Yale University School of Medicine, 295 Congress Avenue, New Haven, CT 06510, USA
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30
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Furuya T, Kiyota T, Lee S, Inoue T, Sugihara G, Logvinova A, Goldsmith P, Ellerby HM. Nanotubules formed by highly hydrophobic amphiphilic alpha-helical peptides and natural phospholipids. Biophys J 2003; 84:1950-9. [PMID: 12609897 PMCID: PMC1302764 DOI: 10.1016/s0006-3495(03)75003-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
We previously reported that the 18-mer amphiphilic alpha-helical peptide, Hel 13-5, consisting of 13 hydrophobic residues and five hydrophilic amino acid residues, can induce neutral liposomes (egg yolk phosphatidylcholine) to adopt long nanotubular structures and that the interaction of specific peptides with specific phospholipid mixtures induces the formation of membrane structures resembling cellular organelles such as the Golgi apparatus. In the present study we focused our attention on the effects of peptide sequence and chain length on the nanotubule formation occurring in mixture systems of Hel 13-5 and various neutral and acidic lipid species by means of turbidity measurements, dynamic light scattering measurements, and electron microscopy. We designed and synthesized two sets of Hel 13-5 related peptides: 1) Five peptides to examine the role of hydrophobic or hydrophilic residues in amphiphilic alpha-helical structures, and 2) Six peptides to examine the role of peptide length, having even number residues from 12 to 24. Conformational, solution, and morphological studies showed that the amphiphilic alpha-helical structure and the peptide chain length (especially 18 amino acid residues) are critical determinants of very long tubular structures. A mixture of alpha-helix and beta-structures determines the tubular shapes and assemblies. However, we found that the charged Lys residues comprising the hydrophilic regions of amphiphilic structures can be replaced by Arg or Glu residues without a loss of tubular structures. This suggests that the mechanism of microtubule formation does not involve the charge interaction. The immersion of the hydrophobic part of the amphiphilic peptides into liposomes initially forms elliptic-like structures due to the fusion of small liposomes, which is followed by a transformation into tubular structures of various sizes and shapes.
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Affiliation(s)
- Tomomi Furuya
- Department of Chemistry, Faculty of Science, Fukuoka University, Japan
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31
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Mercier C, Dubremetz JF, Rauscher B, Lecordier L, Sibley LD, Cesbron-Delauw MF. Biogenesis of nanotubular network in Toxoplasma parasitophorous vacuole induced by parasite proteins. Mol Biol Cell 2002; 13:2397-409. [PMID: 12134078 PMCID: PMC117322 DOI: 10.1091/mbc.e02-01-0021] [Citation(s) in RCA: 126] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The intracellular parasite Toxoplasma gondii develops within a nonfusogenic vacuole containing a network of elongated nanotubules that form connections with the vacuolar membrane. Parasite secretory proteins discharged from dense granules (known as GRA proteins) decorate this intravacuolar network after invasion. Herein, we show using specific gene knockout mutants, that the unique nanotubule conformation of the network is induced by the parasite secretory protein GRA2 and further stabilized by GRA6. The vacuolar compartment generated by GRA2 knockout parasites was dramatically disorganized, and the normally tubular network was replaced by small aggregated material. The defect observed in Deltagra2 parasites was evident from the initial stages of network formation when a prominent cluster of multilamellar vesicles forms at a posterior invagination of the parasite. The secretory protein GRA6 failed to localize properly to this posterior organizing center in Deltagra2 cells, indicating that this early conformation is essential to proper assembly of the network. Construction of a Deltagra6 mutant also led to an altered mature network characterized by small vesicles instead of elongated nanotubules; however, the initial formation of the posterior organizing center was normal. Complementation of the Deltagra2 knockout with mutated forms of GRA2 showed that the integrity of both amphipathic alpha-helices of the protein is required for correct formation of the network. The induction of nanotubues by the parasite protein GRA2 may be a conserved feature of amphipathic alpha-helical regions, which have also been implicated in the organization of Golgi nanotubules and endocytic vesicles in mammalian cells.
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Affiliation(s)
- Corinne Mercier
- Centre National de la Recherche Scientifique FRE 2383, Bâtiment CERMO, Université Joseph Fourier, Grenoble, France 38041
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32
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Affiliation(s)
- Marta Miaczynska
- Max Planck Institute for Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, Dresden, 01307, Germany
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33
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Ishiyama N, Hill CM, Bates IR, Harauz G. The formation of helical tubular vesicles by binary monolayers containing a nickel-chelating lipid and phosphoinositides in the presence of basic polypeptides. Chem Phys Lipids 2002; 114:103-11. [PMID: 11841829 DOI: 10.1016/s0009-3084(02)00002-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Binary lipid monolayers consisting of equimolar proportions of a phosphoinositide and a nickel-chelating lipid formed helical tubular vesicular structures, which appeared to be induced and/or stabilized by myelin basic protein (MBP). Another basic polypeptide, poly-L-lysine, had a similar effect but not to as great a degree as MBP; the proteins thus appeared to act as polycations. Although, the nickel-chelating lipid is a synthetic product, other endogenous divalent cations such as Zn(2+), as well as phosphoinositides, are integral and dynamic components of the myelin sheath in vivo. There, comparable helical tubular structures might represent a means for sequestration of these lipids into domains of high local concentration, perhaps in regions where the membrane is greatly curved.
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Affiliation(s)
- Noboru Ishiyama
- Biophysics Interdepartmental Group, Department of Molecular Biology and Genetics, University of Guelph, 50 Stone Road East, Ont., N1G 2W1, Guelph, Canada
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34
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Ishiyama N, Bates IR, Hill CM, Wood DD, Matharu P, Viner NJ, Moscarello MA, Harauz G. The effects of deimination of myelin basic protein on structures formed by its interaction with phosphoinositide-containing lipid monolayers. J Struct Biol 2001; 136:30-45. [PMID: 11858705 DOI: 10.1006/jsbi.2001.4421] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The recombinant 18.5-kDa charge isoform of murine myelin basic protein (rmMBP) is unmodified posttranslationally and was used to study the effects of deimination, i.e., the conversion of arginyl to citrullinyl residues, on the protein's interactions with itself and with lipids. The unmodified species rmMBP-Cit(0) (i.e., containing no citrullinyl residues) interacted with binary monolayers containing acidic (phosphatidylinositol) and nickel-chelating lipids to form paracrystalline arrays with 4.8-nm spacing. A sample of protein was deiminated to an average of 9 citrullinyl residues per molecule of protein, yielding rmMBP-Cit(9). Under both low- and high-salt conditions, this species formed better-ordered domains than rmMBP-Cit(0), viz., planar crystalline assemblies. Thus, deimination of MBP resulted in a significant alteration of its lipid-organizing and self-interaction properties that might be operative in myelin in vivo, especially in progression of the autoimmune disease multiple sclerosis. Comparisons of amino acid sequences indicated significant similarities of MBP with filaggrin, a protein that is deiminated in another autoimmune disease, rheumatoid arthritis, suggesting that comparable epitopes could be targeted in both pathologies. In contrast, binary lipid monolayers consisting of phosphatidylinositol-4-phosphate (or phosphatidylinositol-4,5-bisphosphate) and a nickel-chelating lipid formed helical tubular vesicular structures, which appeared to be induced and/or stabilized by rmMBP, especially in its deiminated form. Sequence comparisons with other actin- and phosphoinositide-binding proteins (vinculin, ActA, MARCKS) suggested that the carboxyl-terminal segment of MBP could form an amphipathic alpha helix and was the phosphoinositide binding site.
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Affiliation(s)
- N Ishiyama
- Department of Molecular Biology and Genetics, University of Guelph, 50 Stone Road East, Guelph, Ontario, N1G 2W1, Canada
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