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Intracellular and Plasma Membrane Events in Cholesterol Transport and Homeostasis. J Lipids 2018; 2018:3965054. [PMID: 30174957 PMCID: PMC6106919 DOI: 10.1155/2018/3965054] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 07/26/2018] [Indexed: 12/13/2022] Open
Abstract
Cholesterol transport between intracellular compartments proceeds by both energy- and non-energy-dependent processes. Energy-dependent vesicular traffic partly contributes to cholesterol flux between endoplasmic reticulum, plasma membrane, and endocytic vesicles. Membrane contact sites and lipid transfer proteins are involved in nonvesicular lipid traffic. Only “active" cholesterol molecules outside of cholesterol-rich regions and partially exposed in water phase are able to fast transfer. The dissociation of partially exposed cholesterol molecules in water determines the rate of passive aqueous diffusion of cholesterol out of plasma membrane. ATP hydrolysis with concomitant conformational transition is required to cholesterol efflux by ABCA1 and ABCG1 transporters. Besides, scavenger receptor SR-B1 is involved also in cholesterol efflux by facilitated diffusion via hydrophobic tunnel within the molecule. Direct interaction of ABCA1 with apolipoprotein A-I (apoA-I) or apoA-I binding to high capacity binding sites in plasma membrane is important in cholesterol escape to free apoA-I. ABCG1-mediated efflux to fully lipidated apoA-I within high density lipoprotein particle proceeds more likely through the increase of “active” cholesterol level. Putative cholesterol-binding linear motifs within the structure of all three proteins ABCA1, ABCG1, and SR-B1 are suggested to contribute to the binding and transfer of cholesterol molecules from cytoplasmic to outer leaflets of lipid bilayer. Together, plasma membrane events and intracellular cholesterol metabolism and traffic determine the capacity of the cell for cholesterol efflux.
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Matsuzaki N, Handa T, Nakano M. Kinetic and Thermodynamic Analysis of Cholesterol Transfer between Phospholipid Vesicles and Nanodiscs. J Phys Chem B 2015; 119:9764-71. [DOI: 10.1021/acs.jpcb.5b03682] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Naoya Matsuzaki
- Graduate
School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Tetsurou Handa
- Faculty
of Pharmaceutical Sciences, Suzuka University of Medical Science, 3500-3
Minami-Tamagaki-cho, Suzuka, Mie 513-8670, Japan
| | - Minoru Nakano
- Graduate
School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
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Cuellar LÁ, Prieto ED, Cabaleiro LV, Garda HA. Apolipoprotein A-I configuration and cell cholesterol efflux activity of discoidal lipoproteins depend on the reconstitution process. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1841:180-9. [DOI: 10.1016/j.bbalip.2013.10.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Revised: 10/02/2013] [Accepted: 10/24/2013] [Indexed: 12/31/2022]
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Toledo JD, Cabaleiro LV, Garda HA, Gonzalez MC. Effect of reconstituted discoidal high-density lipoproteins on lipid mobilization in RAW 264.7 and CHOK1 cells. J Cell Biochem 2012; 113:1208-16. [PMID: 22095661 DOI: 10.1002/jcb.23453] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Reconstituted discoidal high-density lipoproteins (rHDL) resemble nascent HDL, which are formed at the early reverse cholesterol transport steps, and constitute the initial cholesterol (Chol) acceptors from cell membranes. We have used different sized rHDL containing or not Chol, to test their abilities to promote cholesterol and phospholipid efflux from two different cell lines: Raw 264.7 macrophages and CHOK1 cells. All rHDL and lipid-free apolipoprotein A-I (apoA-I) were found to be bound to CHO and RAW cells. In RAW cells, a positive correlation between cellular binding and Chol removal was found for 78 and 96 Å rHDL. Chol-free rHDL were more effective than Chol-containing ones in binding to RAW cells and promoting Chol removal. These results were more evident in the 96 Å rHDL. On the other hand, rHDL binding to CHO cells was relatively independent of disc size and Chol content. In spite of the fact that apoA-I and rHDL promoted Chol efflux from both cellular lines, only in CHOK1 cells this result was also associated to decrease Chol esterification. Among choline-containing phospholipids, only phosphatidylcholine (PC) (but not sphingomyelin) was detected to be effuxed from both cellular lines. With the only exception of Chol-free 96 Å discs, the other rHDL as well as apoA-I promoted PC efflux from RAW cells. Chol-containing rHDL were more active than Chol-free ones of comparable size to promote PC efflux from RAW macrophages. Regarding CHO cells, only apoA-I and Chol-free 78 Å rHDL were active enough to remove PC.
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Affiliation(s)
- Juan D Toledo
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), CONICET-UNLP, Facultad de Ciencias Médicas, calles 60 y 120, 1900-La Plata, Argentina
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Prieto ED, Garda HA. Membrane insertion topology of the central apolipoprotein A-I region. Fluorescence studies using single tryptophan mutants. Biochemistry 2010; 50:466-79. [PMID: 21141907 DOI: 10.1021/bi1009634] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Apolipoprotein A-I (apoAI) contains several amphipathic α-helices. To carry out its function, it exchanges between lipid-free and different lipidated states as bound to membranes or to lipoprotein complexes of different morphology, size, and composition. When bound to membranes or to spherical lipoprotein surfaces, it is thought that most α-helices arrange with their long axis parallel to the membrane surface. However, we previously found that a central region spanning residues 87-112 is exclusively labeled by photoactivable reagents deeply located into the membrane (Córsico et al. (2001) J. Biol. Chem. 276, 16978-16985). A pair of amphipathic α-helical repeats with a particular charge distribution is predicted in this region. In order to study their insertion topology, three single tryptophan mutants, each one containing the tryptophan residue at a selected position in the hydrophobic face of the central Y-helices (W@93, W@104, and W@108), were used. From the accessibility to quenchers located at different membrane depths, distances from the bilayer center of 13.4, 10.5, and 15.7 Å were estimated for positions 93, 104, and 108, respectively. Reported data also indicate that distances between homologous positions (in particular for W@93 and W@104) are very short in dimers in aqueous solution, but they are larger in membrane-bound dimers. Data indicate that an intermolecular central Y-helix bundle would penetrate the membrane perpendicularly to the membrane surface. Intermolecular helix-helix interactions would occur through the hydrophilic helix faces in the membrane-bound bundle but through the hydrophobic faces in the case of dimers in solution.
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Affiliation(s)
- Eduardo D Prieto
- Instituto de Investigaciones Bioquímicas de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional de La Plata, Facultad de Ciencias Médicas, Calles 60 y 120, La Plata, Argentina
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Goksu EI, Longo ML. Ternary lipid bilayers containing cholesterol in a high curvature silica xerogel environment. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:8614-24. [PMID: 20143868 DOI: 10.1021/la9046885] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The phase behavior of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC)/1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) (1/1 mol ratio)/cholesterol (0-60 mol %) supported lipid bilayers agreed with a DOPC/DSPC/cholesterol ternary phase diagram by Zhao et al. when a mica support was used (Zhao, J.; Wu, J.; Heberle, F. A.; Mills, T. T.; Klawitter, P.; Huang, G.; Costanza, G.; Feigenson, G. W. Biochim. Biophys. Acta, Biomembr. 2007, 1768, 2764-2776). However, when a silica xerogel support was used, the phase behavior deviated from the phase diagram. Specifically, miscibility and trend lines of DSPC-rich domain area fraction, domain shape, and domain size versus cholesterol, obtained by analysis of fluorescence and atomic force microscopy (AFM) images, were as expected for mica-supported lipid bilayers, but were substantially stretched to higher cholesterol concentrations for silica xerogel-supported lipid bilayers. In addition, this behavior was found in three other ternary lipid compositions substituting slightly shorter acyl chain lengths in comparison to DSPC or a saturated lipid versus unsaturated DOPC. Qualitative comparison of domain characteristics of DOPC/DSPC/cholesterol (0 and 15 mol %) bilayers supported by silica xerogel, mica, borosilicate glass, and quartz showed that the networked surface layer of high curvature (0.04 nm(-1)) silica beads was the dominant influence as opposed to the surface chemistry. Based upon the literature, we postulate two curvature-based mechanisms that explain our results. In the first mechanism, cholesterol was transferred from the higher curvature supported lipid bilayer to the lower curvature vesicles in the medium during the vesicle fusion and thermal cooling step, resulting in a lowered cholesterol concentration of the supported lipid bilayer. In the second mechanism, high curvature promoted sustained lipid demixing as the cholesterol concentration was increased, thus creating a new phase diagram in which coexisting phases persist to a higher cholesterol concentration. These results suggest that a surface layer of high curvature features can be used to observe and study curvature-induced intrabilayer transport or demixing over large areas and that curvature can play an important role in sorting and localization of biomembrane components.
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Affiliation(s)
- Emel I Goksu
- Department of Chemical Engineering & Materials Science, University of California, Davis, California 95616, USA
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Vanmierlo T, Rutten K, Dederen J, Bloks VW, van Vark-van der Zee LC, Kuipers F, Kiliaan A, Blokland A, Sijbrands EJG, Steinbusch H, Prickaerts J, Lütjohann D, Mulder M. Liver X receptor activation restores memory in aged AD mice without reducing amyloid. Neurobiol Aging 2009; 32:1262-72. [PMID: 19674815 DOI: 10.1016/j.neurobiolaging.2009.07.005] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2008] [Revised: 06/03/2009] [Accepted: 07/10/2009] [Indexed: 11/19/2022]
Abstract
Alterations in cerebral cholesterol metabolism are thought to play a role in the progression of Alzheimer's disease (AD). Liver X receptors (LXRs) are key regulators of cholesterol metabolism. The synthetic LXR activator, T0901317 has been reported to improve memory functions in animal models for AD and to reduce amyloid-β (Aβ) deposition in the brain. Here we provide evidence that long-term administration of T0901317 to aged, 21-month-old APPSLxPS1mut mice restores impaired memory. Cerebral cholesterol turnover was enhanced as indicated by the increased levels of brain cholesterol precursors and the upregulation of LXR-target genes Abca1, Abcg1, and Apoe. Unexpectedly, the improved memory functions in the APPSLxPS1mut mice after T0901317 treatment were not accompanied by a decrease in Aβ plaque load in the cortex or hippocampus DG, CA1 or CA3. T0901317 administration also enhanced cerebral cholesterol turnover in aged C57BL/6NCrl mice, but did not further improve their memory functions. In conclusion, long-term activation of the LXR-pathway restored memory functions in aged APPSLxPS1mut mice with advanced Aβ deposition. However the beneficial effects of T0901317 on memory in the APPSLxPS1mut mice were independent of the Aβ plaque load in the hippocampus, but were associated with enhanced brain cholesterol turnover.
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Affiliation(s)
- Tim Vanmierlo
- Department of Neuroscience, Maastricht University, Maastricht, The Netherlands
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Massey JB, Pownall HJ, Macha S, Morris J, Tubb MR, Silva RAGD. Mass spectrometric determination of apolipoprotein molecular stoichiometry in reconstituted high density lipoprotein particles. J Lipid Res 2009; 50:1229-36. [PMID: 19179308 DOI: 10.1194/jlr.d800044-jlr200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Plasma HDL-cholesterol and apolipoprotein A-I (apoA-I) levels are strongly inversely associated with cardiovascular disease. However, the structure and protein composition of HDL particles is complex, as native and synthetic discoidal and spherical HDL particles can have from two to five apoA-I molecules per particle. To fully understand structure-function relationships of HDL, a method is required that is capable of directly determining the number of apolipoprotein molecules in heterogeneous HDL particles. Chemical cross-linking followed by SDS polyacrylamide gradient gel electrophoresis has been previously used to determine apolipoprotein stoichiometry in HDL particles. However, this method yields ambiguous results due to effects of cross-linking on protein conformation and, subsequently, its migration pattern on the gel. Here, we describe a new method based on cross-linking chemistry followed by MALDI mass spectrometry that determines the absolute mass of the cross-linked complex, thereby correctly determining the number of apolipoprotein molecules in a given HDL particle. Using well-defined, homogeneous, reconstituted apoA-I-containing HDL, apoA-IV-containing HDL, as well as apoA-I/apoA-II-containing HDL, we have validated this method. The method has the capability to determine the molecular ratio and molecular composition of apolipoprotein molecules in complex reconstituted HDL particles.
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Affiliation(s)
- John B Massey
- Section of Atherosclerosis and Vascular Medicine, Department of Medicine, Baylor College of Medicine, Houston, TX 77030, USA
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Gonzalez MC, Toledo JD, Tricerri MA, Garda HA. The central type Y amphipathic α-helices of apolipoprotein AI are involved in the mobilization of intracellular cholesterol depots. Arch Biochem Biophys 2008; 473:34-41. [DOI: 10.1016/j.abb.2008.02.021] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2008] [Revised: 02/14/2008] [Accepted: 02/16/2008] [Indexed: 01/14/2023]
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Garda HA. Structure–function relationships in human apolipoprotein A-I: role of a central helix pair. ACTA ACUST UNITED AC 2007. [DOI: 10.2217/17460875.2.1.95] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Chapter 7 Lipid Vesicles—Development and Applications for Studding Membrane Heterogeneity and Interactions. ADVANCES IN PLANAR LIPID BILAYERS AND LIPOSOMES 2006. [DOI: 10.1016/s1554-4516(06)05007-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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12
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Puff N, Lamazière A, Seigneuret M, Trugnan G, Angelova MI. HDLs induce raft domain vanishing in heterogeneous giant vesicles. Chem Phys Lipids 2005; 133:195-202. [PMID: 15642587 DOI: 10.1016/j.chemphyslip.2004.10.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2004] [Revised: 10/11/2004] [Accepted: 10/19/2004] [Indexed: 11/15/2022]
Abstract
Cholesterol efflux from the plasma membrane to HDLs is essential for cell cholesterol homeostasis. Recently, cholesterol-enriched ordered membrane domains, i.e. lipid rafts have been proposed to play an important role in this process. Here we introduce a new method to investigate the role of HDL interactions with the raft lipid phase and to directly visualize the effects of HDL-induced cholesterol efflux on rafts in model membranes. Addition of HDLs to giant lipid vesicles containing raft-type domains promoted decrease in size and disappearance of such domains as visualized by fluorescence microscopy. This was interpreted as resulting from cholesterol efflux from the vesicles to the HDLs. The raft vanishing rate was directly related to the HDL concentration. Evidence for a direct interaction of HDLs with the membrane was obtained by observing mutual adhesion of vesicles. It is suggested that the present method can be used to study the selective role of the bilayer lipid phase (raft and non-raft) in cholesterol efflux and membrane-HDL interaction and their underlying mechanisms. Such mechanisms may contribute to cholesterol efflux in vivo.
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Affiliation(s)
- Nicolas Puff
- Laboratoire de Physicochimie Biomoléculaire et Cellulaire, Université Pierre et Marie Curie, CNRS UMR 7033, Case 138, 4 Place Jussieu, 75252 Paris, Cedex 05, France
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Toledo JD, Prieto ED, Gonzalez MC, Soulages JL, Garda HA. Functional independence of a peptide with the sequence of human apolipoprotein A-I central region. Arch Biochem Biophys 2004; 428:188-97. [PMID: 15246876 DOI: 10.1016/j.abb.2004.05.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2004] [Revised: 05/10/2004] [Indexed: 11/23/2022]
Abstract
Previous results [J. Biol. Chem. 276 (2001) 16978] indicated that an apolipoprotein A-I (apoAI) central region swings away from lipid contact in discoidal high density lipoproteins (HDL), but it is able to penetrate into the bilayer of lipid vesicles. In this work, we have studied the interaction with lipid membranes of a synthetic peptide with the sequence of apoAI region between residues 77 and 120 (AI 77-120). Like apoAI, AI 77-120 binds to phospholipid vesicles and shows selectivity for cholesterol-containing membranes. Moreover, AI 77-120 promotes cholesterol desorption from membranes in a similar fashion as apoAI and can stimulate cholesterol efflux from Chinese hamster ovary cells. AI 77-120 has a considerable alpha-helical content in water solution, and its secondary structure is not largely modified after binding to membranes. Both apoA-I and AI 77-120 are oligomeric in the lipid-bound state, suggesting that dimerization of the central domain could be required for the membrane binding activity of apoA-I in HDL.
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Affiliation(s)
- Juan Domingo Toledo
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP)-Consejo Nacional de Investigaciones Científicas y Técnicas / Universidad Nacional de La Plata, Facultad de Ciencias Médicas, Calles 60 y 120, 1900 La Plata, Argentina
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Sigalov AB, Stern LJ. Oxidation of methionine residues affects the structure and stability of apolipoprotein A-I in reconstituted high density lipoprotein particles. Chem Phys Lipids 2001; 113:133-46. [PMID: 11687233 DOI: 10.1016/s0009-3084(01)00186-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
To determine the effect of oxidative damage to lipid-bound apolipoprotein A-I (apo A-I) on its structure and stability that might be related to previously observed functional disorders of oxidized apo A-I in high density lipoproteins (HDL), we prepared homogeneous reconstituted HDL (rHDL) particles containing unoxidized apo A-I and its commonly occurring oxidized form (Met-112, 148 bis-sulfoxide). The size of the obtained discoidal rHDL particles ranged from 9.0 to 10.0 nm and did not depend upon the content of the oxidized protein. Using circular dichroism methods, no change in the secondary structure of lipid-bound oxidized apo A-I was found. Isothermal and thermal denaturation experiments showed a significant destabilization of the oxidized protein to denaturation by guanidine hydrochloride or heat. This effect was observed with and without co-reconstituted apolipoprotein A-II. Limited tryptic digestion indicated that the central region of oxidatively damaged apo A-I becomes exposed to proteolysis in the rHDL particles. Implications of these data for apolipoprotein function are discussed.
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Affiliation(s)
- A B Sigalov
- Biomedical Department, AMW Biomed, 22-1-11 Tarusskaya Street, Moscow 117588, Russia.
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Córsico B, Toledo JD, Garda HA. Evidence for a central apolipoprotein A-I domain loosely bound to lipids in discoidal lipoproteins that is capable of penetrating the bilayer of phospholipid vesicles. J Biol Chem 2001; 276:16978-85. [PMID: 11278925 DOI: 10.1074/jbc.m011533200] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Previous evidence indicated that discoidal reconstituted high density lipoproteins (rHDL) of apolipoprotein A-I (apoA-I) can interact with lipid membranes (Tricerri, M. A., Córsico, B., Toledo, J. D., Garda, H. A., and Brenner, R. R. (1998) Biochim. Biophys. Acta 1391, 67-78). With the aim of studying this interaction, photoactivable reagents and protein cleavage with CNBr and hydroxylamine were used. The generic hydrophobic reagent 3-(trifluoromethyl)-3-(m-[125I]iodophenyl)diazirine gave information on the apoA-I regions in contact with the lipid phase in the rHDL discs. Two protein regions loosely bound to lipids were detected: a C-terminal domain and a central one located between residues 87 and 112. They consist of class Y amphipathic alpha-helices that have a different distribution of the charged residues in their polar faces by comparison with class A helices, which predominate in the rest of the apoA-I molecule. The phospholipid analog 1-O-hexadecanoyl-2-O-[9-[[[2-[125I]iodo-4-(trifluoro-methyl-3-H-diazirin-3-yl)benzyl]oxy]carbonyl]nonanoyl]-sn-glycero-3-phosphocholine, which does not undergo significant exchange between membranes and lipoproteins, was used to identify the apoA-I domain directly involved in the interaction of rHDL discs with membranes. By incubating either rHDL or lipid-free apoA-I with lipid vesicles containing 125I-TID-PC, only the 87-112 apoA-I segment becomes labeled after photoactivation. These results indicate that the central domain formed by two type Y helices swings away from lipid contact in the discoidal lipoproteins and is able to insert into membrane bilayers, a process that may be of great importance for the mechanism of cholesterol exchange between high density lipoproteins and cell membranes.
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Affiliation(s)
- B Córsico
- Instituto de Investigaciones Bioquimicas de La Plata-Consejo Nacional de Investigaciones Científicas y Técnicas/Universidad Nacional de La Plata, Facultad de Ciencias Médicas, Calles 60 y 120, 1900 La Plata, Argentina
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