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Kamperman T, Willemen NGA, Kelder C, Koerselman M, Becker M, Lins L, Johnbosco C, Karperien M, Leijten J. Steering Stem Cell Fate within 3D Living Composite Tissues Using Stimuli-Responsive Cell-Adhesive Micromaterials. Adv Sci (Weinh) 2023; 10:e2205487. [PMID: 36599686 PMCID: PMC10074101 DOI: 10.1002/advs.202205487] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 11/28/2022] [Indexed: 06/12/2023]
Abstract
Engineered living microtissues such as cellular spheroids and organoids have enormous potential for the study and regeneration of tissues and organs. Microtissues are typically engineered via self-assembly of adherent cells into cellular spheroids, which are characterized by little to no cell-material interactions. Consequently, 3D microtissue models currently lack structural biomechanical and biochemical control over their internal microenvironment resulting in suboptimal functional performance such as limited stem cell differentiation potential. Here, this work report on stimuli-responsive cell-adhesive micromaterials (SCMs) that can self-assemble with cells into 3D living composite microtissues through integrin binding, even under serum-free conditions. It is demonstrated that SCMs homogeneously distribute within engineered microtissues and act as biomechanically and biochemically tunable designer materials that can alter the composite tissue microenvironment on demand. Specifically, cell behavior is controlled based on the size, stiffness, number ratio, and biofunctionalization of SCMs in a temporal manner via orthogonal secondary crosslinking strategies. Photo-based mechanical tuning of SCMs reveals early onset stiffness-controlled lineage commitment of differentiating stem cell spheroids. In contrast to conventional encapsulation of stem cell spheroids within bulk hydrogel, incorporating cell-sized SCMs within stem cell spheroids uniquely provides biomechanical cues throughout the composite microtissues' volume, which is demonstrated to be essential for osteogenic differentiation.
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Affiliation(s)
- Tom Kamperman
- Department of Developmental BioEngineeringFaculty of Science and TechnologyTechnical Medical CentreUniversity of TwenteDrienerlolaan 5Enschede7522NBThe Netherlands
| | - Niels G. A. Willemen
- Department of Developmental BioEngineeringFaculty of Science and TechnologyTechnical Medical CentreUniversity of TwenteDrienerlolaan 5Enschede7522NBThe Netherlands
| | - Cindy Kelder
- Department of Developmental BioEngineeringFaculty of Science and TechnologyTechnical Medical CentreUniversity of TwenteDrienerlolaan 5Enschede7522NBThe Netherlands
| | - Michelle Koerselman
- Department of Developmental BioEngineeringFaculty of Science and TechnologyTechnical Medical CentreUniversity of TwenteDrienerlolaan 5Enschede7522NBThe Netherlands
| | - Malin Becker
- Department of Developmental BioEngineeringFaculty of Science and TechnologyTechnical Medical CentreUniversity of TwenteDrienerlolaan 5Enschede7522NBThe Netherlands
| | - Luanda Lins
- Department of Developmental BioEngineeringFaculty of Science and TechnologyTechnical Medical CentreUniversity of TwenteDrienerlolaan 5Enschede7522NBThe Netherlands
| | - Castro Johnbosco
- Department of Developmental BioEngineeringFaculty of Science and TechnologyTechnical Medical CentreUniversity of TwenteDrienerlolaan 5Enschede7522NBThe Netherlands
| | - Marcel Karperien
- Department of Developmental BioEngineeringFaculty of Science and TechnologyTechnical Medical CentreUniversity of TwenteDrienerlolaan 5Enschede7522NBThe Netherlands
| | - Jeroen Leijten
- Department of Developmental BioEngineeringFaculty of Science and TechnologyTechnical Medical CentreUniversity of TwenteDrienerlolaan 5Enschede7522NBThe Netherlands
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Rondelli V, Koutsioubas A, Pršić J, Deboever E, Crowet JM, Lins L, Deleu M. Sitosterol and glucosylceramide cooperative transversal and lateral uneven distribution in plant membranes. Sci Rep 2021; 11:21618. [PMID: 34732753 PMCID: PMC8566578 DOI: 10.1038/s41598-021-00696-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 07/29/2021] [Accepted: 10/05/2021] [Indexed: 11/13/2022] Open
Abstract
The properties of biomembranes depend on the presence, local structure and relative distribution assumed by the thousands of components it is made of. As for animal cells, plant membranes have been demonstrated to be organized in subdomains with different persistence lengths and times. In plant cells, sitosterol has been demonstrated to confer to phospholipid membranes a more ordered structure while among lipids, glycosphingolipids are claimed to form rafts where they tightly pack with sterols. Glucosylceramides are glycosphingolipids involved in plant signalling and are essential for viability of cells and whole plant. The glucosylceramide-sitosterol structural coupling within PLPC membranes is here investigated by Langmuir films, in silico simulations and neutron reflectometry, unveiling that a strong direct interaction between the two molecules exists and governs their lateral and transversal distribution within membrane leaflets. The understanding of the driving forces governing specific molecules clustering and segregation in subdomains, such as glucosylceramide and sitosterol, have an impact on the mechanical properties of biomembranes and could reflect in the other membrane molecules partitioning and activity.
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Affiliation(s)
- V Rondelli
- Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milano, Italy.
| | - A Koutsioubas
- Jülich Centre for Neutron Science at Heinz Maier-Leibnitz Zentrum, Forschungszentrum Jülich GmbH, Garching, Germany.
| | - J Pršić
- Microbial Processes and Interactions Laboratory (MiPI), TERRA Research Center, Gembloux Agro-Bio Tech, Université de Liège, Gembloux, Belgium
| | - E Deboever
- Laboratoire de Biophysique Moléculaire aux Interfaces, Structure Fédérative de Recherche Condorcet, TERRA Research Center, Gembloux Agro-Bio Tech, Université de Liège, Gembloux, Belgium.,Laboratory of Natural Molecules Chemistry, Gembloux Agro-Bio Tech, University of Liège, 2, Passage des Déportés, 5030, Gembloux, Belgium.,FytoFend S.A., rue Georges Legrand, 6, 5032, Isnes, Belgium
| | - J M Crowet
- Université de Reims Champagne-Ardenne, UFR Sciences Exactes et Naturelles, Reims, France
| | - L Lins
- Laboratoire de Biophysique Moléculaire aux Interfaces, Structure Fédérative de Recherche Condorcet, TERRA Research Center, Gembloux Agro-Bio Tech, Université de Liège, Gembloux, Belgium
| | - M Deleu
- Laboratoire de Biophysique Moléculaire aux Interfaces, Structure Fédérative de Recherche Condorcet, TERRA Research Center, Gembloux Agro-Bio Tech, Université de Liège, Gembloux, Belgium.
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Bailer M, Teixeira S, Oliveira V, Rodrigues R, Capelloza R, Ferrari E, Mazucatto I, Sanches M, Lazo G, Lins L. Is it possible to reach the patient's caloric goal within 72 hours after hospital admission? Clin Nutr ESPEN 2020. [DOI: 10.1016/j.clnesp.2020.09.307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Mazucatto I, Totti F, Longhi S, Alves F, Lins L, Bailer M, Navarro G, Ogeda E. Implementation and segment of fasting abbreviation project in a private hospital in the city of São paulo - Brazil. We are ready? Clin Nutr ESPEN 2020. [DOI: 10.1016/j.clnesp.2020.09.567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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5
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Bailer M, Teixeira S, Oliveira V, Botelho F, Capelloza R, Mazucatto I, Rangel B, Lins L, Ferreira E, Carvalho V. Monitoring of dietary administration in patients with enteral nutritional therapy using a prescribed volume X infused volume indicator. Clin Nutr ESPEN 2020. [DOI: 10.1016/j.clnesp.2020.09.306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Pazeto C, Timoteo F, Moschovas M, Lins L, Korkes F, Neves O. Robotic ureteral reimplantation due to deep infiltrating endometriosis - psoas hitch approach. EUR UROL SUPPL 2020. [DOI: 10.1016/s2666-1683(20)35883-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Lins L, Wianny F, Dehay C, Jestin J, Loh W. Adhesive Sponge Based on Supramolecular Dimer Interactions as Scaffolds for Neural Stem Cells. Biomacromolecules 2020; 21:3394-3410. [PMID: 32584556 DOI: 10.1021/acs.biomac.0c00825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Improving cell-material interactions of nonadhesive scaffolds is crucial for the success of biomaterials in tissue engineering. Due to their high surface area and open pore structure, sponges are widely reported as absorbent materials for biomedical engineering. The biocompatibility and biodegradability of polysaccharide sponges, coupled with the chemical functionalities of supramolecular dimers, make them promising combinations for the development of adhesive scaffolds. Here, a supramolecular tactic based on (UPy)-modified polysaccharide associated with three-dimensional structure of sponges was developed to reach enhanced cellular adhesion. For this purpose, three approaches were examined individually in order to accomplish this goal. In the first approach, the backbone polysaccharides with noncell adhesive properties were modified via a modular tactic using UPy-dimers. Hereupon, the physical-chemical characterizations of the supramolecular sponges were performed, showing that the presence of supramolecular dimers improved their mechanical properties and induced different architectures. In addition, small-angle neutron scattering (SANS) measurements and rheology experiments revealed that the UPy-dimers into agarose backbone are able to reorganize in thinning aggregates. It is also demonstrated that the resulted UPy-agarose (AGA-UPy) motifs in surfaces can promote cell adhesion. Finally, the last approach showed the great potential for use of this novel material in bioadhesive scaffolds indicating that neural stem cells show a spreading bias in soft materials and that cell adhesion was enhanced for all UPy-modified sponges compared to the reference, i.e. unmodified sponges. Therefore, by functionalizing sponge surfaces with UPy-dimers, an adhesive supramolecular scaffold is built which opens the opportunity its use neural tissues regeneration.
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Affiliation(s)
- Luanda Lins
- Institute of Chemistry, University of Campinas (UNICAMP), Campinas, SP 13083-970, Brazil
| | - Florence Wianny
- Univ Lyon, Université Claude Bernard Lyon 1, INSERM, Stem Cell and Brain Research Institute U1208, 69500 Bron, France
| | - Colette Dehay
- Univ Lyon, Université Claude Bernard Lyon 1, INSERM, Stem Cell and Brain Research Institute U1208, 69500 Bron, France
| | - Jacques Jestin
- Laboratoire Léon Brillouin, UMR12, Bat 563 CEA Saclay, 91191 Gif sur Yvette Cedex, France
| | - Watson Loh
- Institute of Chemistry, University of Campinas (UNICAMP), Campinas, SP 13083-970, Brazil
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Franche A, Fayeulle A, Lins L, Billamboz M, Pezron I, Deleu M, Léonard E. Amphiphilic azobenzenes: Antibacterial activities and biophysical investigation of their interaction with bacterial membrane lipids. Bioorg Chem 2020; 94:103399. [DOI: 10.1016/j.bioorg.2019.103399] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 10/23/2019] [Accepted: 10/24/2019] [Indexed: 01/22/2023]
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9
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Lins L, Alencar Junior F, Fernandes R. PMH2 THE ENVIRONMENT DISASTER OF BRAZILIAN MINING OF MARIANA IN THE HEALTH ECONOMIC CONTEXT: PSYCHOLOGICAL TRAGEDY COST. Value Health Reg Issues 2019. [DOI: 10.1016/j.vhri.2019.08.283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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10
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Sallum F, Aguiar E, Lins L, Pontes Á, Amaral L, Fernandes R. PMU12 A NON-COMMUNICABLE DISEASES MULTI-CRITERIA ANALYSIS IN LATIN AMERICA. Value Health Reg Issues 2019. [DOI: 10.1016/j.vhri.2019.08.326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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11
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Mazucatto I, Longhi S, Totti F, Lazo G, Alves F, Lins L, Sanches L. SUN-PO236: Evaluation of Muscle Mass Loss Related to the Time of Mechanical Ventilation, Diagnosis and Age. Is there a Relationship? Clin Nutr 2019. [DOI: 10.1016/s0261-5614(19)32868-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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12
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Mazucatto I, Longhi S, Totti F, Alves F, Lins L, Nascimento C, Arrais A, Paiva T, Sanches L. SUN-PO237: Nutric Score X NRS Nutritional Risk Screening. Is There Difference in Results in the Same Population? Clin Nutr 2019. [DOI: 10.1016/s0261-5614(19)32869-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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13
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Sanches L, Alves F, Totti F, Buonso I, Bailer M, Nascimento C, Lins L, Jordão M, Longhi S. Nutritional support: Delivery versus energy requirements. Clin Nutr 2018. [DOI: 10.1016/j.clnu.2018.06.1508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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14
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Totti F, Guimarães M, Sanches L, Paraizo V, Lins L, Santos R, Alves F, Ferreirea D, Cukier C. SUN-P186: Implementation of the Training Course of Nursing Referral in Nutritional Therapy. Clin Nutr 2017. [DOI: 10.1016/s0261-5614(17)30442-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Sanches L, Totti F, Alves F, Guimaraes M, Lins L, Arrais A, Paraiso V, Ferreira D. SUN-P185: Observational Study: Protein Target Adequacy and New Challenges. Clin Nutr 2017. [DOI: 10.1016/s0261-5614(17)30443-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Baldan RCF, Coracin FL, Lins L, Mello WR, Santos PS. Atrophic Maxilla Reconstruction With Fresh Frozen Allograft Bone, Titanium Mesh, and Platelet-Rich Fibrin: Case Report. Transplant Proc 2017; 49:893-897. [PMID: 28457420 DOI: 10.1016/j.transproceed.2017.01.053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The purpose of this article was to report the clinical and radiographic findings about a case of a man affected by severely atrophic maxilla to demonstrate the clinical proceedings associated with alveolar reconstruction destined for dental implant rehabilitation. The 3-dimensional augmentation of the alveolar ridge with the use of fresh-frozen bone graft, platelet-rich fibrin membrane, and titanium mesh suggests potential benefits to the development of the bone formation physiology. The treatment combination may result in an optimal prognosis and represents an option for reconstruction of bone defects. At 8 months after surgery, no evidence of complications was observed; the clinical examination and computerized tomographic scan revealed bone formation and installed implant stability.
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Affiliation(s)
- R C F Baldan
- Dental Commission, Brazilian Association of Organ Transplantation, São Paulo, Brazil.
| | - F L Coracin
- Dental Commission, Brazilian Association of Organ Transplantation, São Paulo, Brazil
| | - L Lins
- Dental Commission, Brazilian Association of Organ Transplantation, São Paulo, Brazil
| | - W R Mello
- Dental Commission, Brazilian Association of Organ Transplantation, São Paulo, Brazil
| | - P S Santos
- Dental Commission, Brazilian Association of Organ Transplantation, São Paulo, Brazil
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Lebecque S, Crowet J, Nasir M, Deleu M, Lins L. Molecular dynamics study of micelles properties according to their size. J Mol Graph Model 2017; 72:6-15. [DOI: 10.1016/j.jmgm.2016.12.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 12/07/2016] [Accepted: 12/09/2016] [Indexed: 11/26/2022]
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18
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Sanches L, Bailer M, Totti F, Alves F, Guimarães M, Raiher S, Lins L, Buonso I. SUN-P153: How Much of the Caloric Needs are Met on Enteral Feeding Patients? Clin Nutr 2016. [DOI: 10.1016/s0261-5614(16)30496-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Alves F, Lins L, Rodrigues G. MON-PP163: Nutritional Status of Patients Admitted in a Private Hospital in São Paulo, Brazil. Clin Nutr 2015. [DOI: 10.1016/s0261-5614(15)30595-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Bailer M, Rodrigues G, Alves F, Lins L. SUN-PP089: Assessment of Nutritional Status before and After Protocol Implementation Specialized in Attending the Elderly Hospitalized. Clin Nutr 2015. [DOI: 10.1016/s0261-5614(15)30240-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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21
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Nsimba Zakanda F, Lins L, Nott K, Paquot M, Mvumbi Lelo G, Deleu M. Interaction of hexadecylbetainate chloride with biological relevant lipids. Langmuir 2012; 28:3524-33. [PMID: 22263671 DOI: 10.1021/la2040328] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The present work investigates the interaction of hexadecylbetainate chloride (C(16)BC), a glycine betaine-based ester with palmitoyl-oleoyl-phosphatidylcholine (POPC), sphingomyelin (SM), and cholesterol (CHOL), three biological relevant lipids present in the outer leaflet of the mammalian plasma membrane. The binding affinity and the mixing behavior between the lipids and C(16)BC are discussed based on experimental (isothermal titration calorimetry (ITC) and Langmuir film balance) and molecular modeling studies. The results show that the interaction between C(16)BC and each lipid is thermodynamically favorable and does not affect the integrity of the lipid vesicles. The primary adsorption of C(16)BC into the lipid film is mainly governed by a hydrophobic effect. Once C(16)BC is inserted in the lipid film, the polar component of the interaction energy between C(16)BC and the lipid becomes predominant. Presence of CHOL increases the affinity of C(16)BC for membrane. This result can be explained by the optimal matching between C(16)BC and CHOL within the film rather by a change of membrane fluidity due to the presence of CHOL. The interaction between C(16)BC and SM is also favorable and gives rise to highly stable monolayers probably due to hydrogen bonds between their hydrophilic groups. The interaction of C(16)BC with POPC is less favorable but does not destabilize the mixed monolayer from a thermodynamic point of view. Interestingly, for all the monolayers investigated, the exclusion surface pressures are above the presumed lateral pressure of the plasma membranes suggesting that C(16)BC would be able to penetrate into mammalian plasma membranes in vivo. These results may serve as a useful basis in understanding the interaction of C(16)BC with real membranes.
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Affiliation(s)
- F Nsimba Zakanda
- Unité de Chimie Biologique Industrielle, Gembloux Agro-Bio Tech-University of Liege, Passage des Déportés 2, 5030 Gembloux, Belgium
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Ravault S, Flore C, Saurel O, Milon A, Brasseur R, Lins L. Study of the specific lipid binding properties of Abeta 11-22 fragment at endosomal pH. Langmuir 2009; 25:10948-10953. [PMID: 19735146 DOI: 10.1021/la901544g] [Citation(s) in RCA: 4] [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] [Indexed: 05/28/2023]
Abstract
Increasing evidence implicates interactions between Abeta peptide and lipids in the development of Alzheimer's disease. More generally, Abeta peptide interactions with membranes seem to depend on the composition of the lipid bilayer and the structural features of the peptide. One key parameter should be pH, since one site of intracellular Abeta peptide production and/or accumulation is likely to be endosomes. This intracellular endosomal accumulation was suggested to contribute to disease progression. In this paper, we report a study on the 11-22 amphiphilic domain of Abeta in interaction with model membrane; this region contains most of the charged residues of the N-terminal domain of Abeta. We show that the peptide charge, and more precisely the protonation state of histidines 13 and/or 14, is important for the interaction with lipids. Hence, it is only at endosomal pH that a conformational change of the peptide is observed in the presence of negatively charged lipid vesicles, that is, when both lipid headgroups and histidines can interact through electrostatic interactions. Specific interactions of the fragment with phosphatidylserine and to a lesser extent with phosphatidylcholine, but not phosphatidylethanolamine, are further evidenced by the Langmuir monolayer technique. From our results, we suggest that the protonation state of His residues could have a role in the pathogenic surface interaction of the whole Abeta peptide with membranes.
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Affiliation(s)
- S Ravault
- Centre de Biophysique Moléculaire Numérique, Agricultural University of Gembloux, 5030 Gembloux, Belgium
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Santini S, Crowet JM, Thomas A, Paquot M, Vandenbol M, Thonart P, Wathelet JP, Blecker C, Lognay G, Brasseur R, Lins L, Charloteaux B. Study of Thermomyces lanuginosa lipase in the presence of tributyrylglycerol and water. Biophys J 2009; 96:4814-25. [PMID: 19527641 DOI: 10.1016/j.bpj.2009.03.040] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2008] [Revised: 02/09/2009] [Accepted: 03/24/2009] [Indexed: 10/20/2022] Open
Abstract
The Thermomyces lanuginosa lipase has been extensively studied in industrial and biotechnological research because of its potential for triacylglycerol transformation. This protein is known to catalyze both hydrolysis at high water contents and transesterification in quasi-anhydrous conditions. Here, we investigated the Thermomyces lanuginosa lipase structure in solution in the presence of a tributyrin aggregate using 30 ns molecular-dynamics simulations. The water content of the active-site groove was modified between the runs to focus on the protein-water molecule interactions and their implications for protein structure and protein-lipid interactions. The simulations confirmed the high plasticity of the lid fragment and showed that lipid molecules also bind to a secondary pocket beside the lid. Together, these results strongly suggest that the lid plays a role in the anchoring of the protein to the aggregate. The simulations also revealed the existence of a polar channel that connects the active-site groove to the outside solvent. At the inner extremity of this channel, a tyrosine makes hydrogen bonds with residues interacting with the catalytic triad. This system could function as a pipe (polar channel) controlled by a valve (the tyrosine) that could regulate the water content of the active site.
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Affiliation(s)
- S Santini
- Center of Numerical Molecular Biophysics, Gembloux Agricultural University, Gembloux, Belgium
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Lins L, El Kirat K, Charloteaux B, Flore C, Stroobant V, Thomas A, Dufrene Y, Brasseur R. Lipid-destabilizing properties of the hydrophobic helices H8 and H9 from colicin E1. Mol Membr Biol 2009; 24:419-30. [PMID: 17710646 DOI: 10.1080/09687860701228254] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [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: 10/22/2022]
Abstract
Colicins are toxic proteins produced by Escherichia coli that must cross the membrane to exert their activity. The lipid insertion of their pf domain is linked to a conformational change which enables the penetration of a hydrophobic hairpin. They provide useful models to more generally study insertion of proteins, channel formation and protein translocation in and across membranes. In this paper, we study the lipid-destabilizing properties of helices H8 and H9 forming the hydrophobic hairpin of colicin E1. Modelling analysis suggests that those fragments behave like tilted peptides. The latter are characterized by an asymmetric distribution of their hydrophobic residues when helical. They are able to interact with a hydrophobic/hydrophilic interface (such as a lipid membrane) and to destabilize the organized system into which they insert. Fluorescence techniques using labelled liposomes clearly show that H9, and H8 to a lesser extent, destabilize lipid particles, by inducing fusion and leakage. AFM assays clearly indicate that H8 and especially H9 induce membrane fragilization. Holes in the membrane are even observed in the presence of H9. This behaviour is close to what is seen with viral fusion peptides. Those results suggest that the peptides could be involved in the toroidal pore formation of colicin E1, notably by disturbing the lipids and facilitating the insertion of the other, more hydrophilic, helices that will form the pore. Since tilted, lipid-destabilizing fragments are also common to membrane proteins and to signal sequences, we suggest that tilted peptides should have an ubiquitous role in the mechanism of insertion of proteins into membranes.
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Affiliation(s)
- L Lins
- Centre de Biophysique Moléculaire Numérique, Faculté des Sciences, Agronomiques de Gembloux, Gembloux, Belgium.
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Charloteaux B, Lorin A, Brasseur R, Lins L. The “Tilted Peptide Theory” Links Membrane Insertion Properties and Fusogenicity of Viral Fusion Peptides. Protein Pept Lett 2009; 16:718-25. [DOI: 10.2174/092986609788681724] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Dorfmeister B, Zeng WW, Dichlberger A, Nilsson SK, Schaap FG, Hubacek JA, Merkel M, Cooper JA, Lookene A, Putt W, Whittall R, Lee PJ, Lins L, Delsaux N, Nierman M, Kuivenhoven JA, Kastelein JJP, Vrablik M, Olivecrona G, Schneider WJ, Heeren J, Humphries SE, Talmud PJ. Effects of six APOA5 variants, identified in patients with severe hypertriglyceridemia, on in vitro lipoprotein lipase activity and receptor binding. Arterioscler Thromb Vasc Biol 2008; 28:1866-71. [PMID: 18635818 DOI: 10.1161/atvbaha.108.172866] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The purpose of this study was to identify rare APOA5 variants in 130 severe hypertriglyceridemic patients by sequencing, and to test their functionality, since no patient recall was possible. METHODS AND RESULTS We studied the impact in vitro on LPL activity and receptor binding of 3 novel heterozygous variants, apoAV-E255G, -G271C, and -H321L, together with the previously reported -G185C, -Q139X, -Q148X, and a novel construct -Delta139 to 147. Using VLDL as a TG-source, compared to wild type, apoAV-G255, -L321 and -C185 showed reduced LPL activation (-25% [P=0.005], -36% [P<0.0001], and -23% [P=0.02]), respectively). ApoAV-C271, -X139, -X148, and Delta139 to 147 had little affect on LPL activity, but apoAV-X139, -X148, and -C271 showed no binding to LDL-family receptors, LR8 or LRP1. Although the G271C proband carried no LPL and APOC2 mutations, the H321L carrier was heterozygous for LPL P207L. The E255G carrier was homozygous for LPL W86G, yet only experienced severe hypertriglyceridemia when pregnant. CONCLUSIONS The in vitro determined function of these apoAV variants only partly explains the high TG levels seen in carriers. Their occurrence in the homozygous state, coinheritance of LPL variants or common APOA5 TG-raising variant in trans, appears to be essential for their phenotypic expression.
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Affiliation(s)
- B Dorfmeister
- Department of Medicine, Division of Cardiovascular Genetics, UCL, London, UK
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Fa N, Lins L, Courtoy PJ, Dufrêne Y, Van Der Smissen P, Brasseur R, Tyteca D, Mingeot-Leclercq MP. Decrease of elastic moduli of DOPC bilayers induced by a macrolide antibiotic, azithromycin. Biochimica et Biophysica Acta (BBA) - Biomembranes 2007; 1768:1830-8. [PMID: 17537401 DOI: 10.1016/j.bbamem.2007.04.013] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2007] [Revised: 04/06/2007] [Accepted: 04/10/2007] [Indexed: 10/23/2022]
Abstract
The elastic properties of membrane bilayers are key parameters that control its deformation and can be affected by pharmacological agents. Our previous atomic force microscopy studies revealed that the macrolide antibiotic, azithromycin, leads to erosion of DPPC domains in a fluid DOPC matrix [A. Berquand, M. P. Mingeot-Leclercq, Y. F. Dufrene, Real-time imaging of drug-membrane interactions by atomic force microscopy, Biochim. Biophys. Acta 1664 (2004) 198-205.]. Since this observation could be due to an effect on DOPC cohesion, we investigated the effect of azithromycin on elastic properties of DOPC giant unilamellar vesicles (GUVs). Microcinematographic and morphometric analyses revealed that azithromycin addition enhanced lipid membranes fluctuations, leading to eventual disruption of the largest GUVs. These effects were related to change of elastic moduli of DOPC, quantified by the micropipette aspiration technique. Azithromycin decreased both the bending modulus (k(c), from 23.1+/-3.5 to 10.6+/-4.5 k(B)T) and the apparent area compressibility modulus (K(app), from 176+/-35 to 113+/-25 mN/m). These data suggested that insertion of azithromycin into the DOPC bilayer reduced the requirement level of both the energy for thermal fluctuations and the stress to stretch the bilayer. Computer modeling of azithromycin interaction with DOPC bilayer, based on minimal energy, independently predicted that azithromycin (i) inserts at the interface of phospholipid bilayers, (ii) decreases the energy of interaction between DOPC molecules, and (iii) increases the mean surface occupied by each phospholipid molecule. We conclude that azithromycin inserts into the DOPC lipid bilayer, so as to decrease its cohesion and to facilitate the merging of DPPC into the DOPC fluid matrix, as observed by atomic force microscopy. These investigations, based on three complementary approaches, provide the first biophysical evidence for the ability of an amphiphilic antibiotic to alter lipid elastic moduli. This may be an important determinant for drug: lipid interactions and cellular pharmacology.
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Affiliation(s)
- N Fa
- Université Catholique de Louvain, Unité de Pharmacologie Cellulaire et Moléculaire, Avenue E. Mounier 73, Bt 7370, B-1200 Brussels, Belgium
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Lorin A, Thomas A, Stroobant V, Brasseur R, Lins L. Lipid-destabilising properties of a peptide with structural plasticity. Chem Phys Lipids 2006; 141:185-96. [PMID: 16672156 DOI: 10.1016/j.chemphyslip.2006.02.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2005] [Accepted: 02/20/2006] [Indexed: 11/24/2022]
Abstract
The Chameleon peptide (Cham) is a peptide designed from two regions of the GB1 protein, one folded as an alpha-helix and the other as a beta structure. Depending on the environment, the Cham peptide adopts an alpha or a beta conformation when inserted in different locations of GB1. This environment dependence is also observed for tilted peptides. These short protein fragments, able to destabilise organised system, are mainly folded in beta structure in water and in alpha helix in a hydrophobic environment, like the lipid bilayer. In this paper, we tested whether the Cham peptide can be qualified as a tilted peptide. For this, we have compared the properties of Cham peptide (hydrophobicity, destabilising properties, conformation) to those of tilted peptides. The results suggest that Cham is a tilted peptide. Our study, together the presence of tilted fragments in transconformational proteins, suggests a relationship between tilted peptides and structural lability.
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Affiliation(s)
- A Lorin
- Centre de Biophysique Moléculaire Numérique, Faculté Universitaire des Sciences Agronomiques, Gembloux, Belgium
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30
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Charloteaux B, Lorin A, Crowet JM, Stroobant V, Lins L, Thomas A, Brasseur R. The N-terminal 12 Residue Long Peptide of HIV gp41 is the Minimal Peptide Sufficient to Induce Significant T-cell-like Membrane Destabilization in Vitro. J Mol Biol 2006; 359:597-609. [PMID: 16677669 DOI: 10.1016/j.jmb.2006.04.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2006] [Accepted: 04/03/2006] [Indexed: 11/26/2022]
Abstract
Here, we predicted the minimal N-terminal fragment of gp41 required to induce significant membrane destabilization using IMPALA. This algorithm is dedicated to predict peptide interaction with a membrane. We based our prediction of the minimal fusion peptide on the tilted peptide theory. This theory proposes that some protein fragments having a peculiar distribution of hydrophobicity adopt a tilted orientation at a hydrophobic/hydrophilic interface. As a result of this orientation, tilted peptides should disrupt the interface. We analysed in silico the membrane-interacting properties of gp41 N-terminal peptides of different length derived from the isolate BRU and from an alignment of 710 HIV strains available on the Los Alamos National Laboratory. Molecular modelling results indicated that the 12 residue long peptide should be the minimal fusion peptide. We then assayed lipid-mixing and leakage of T-cell-like liposomes with N-terminal peptides of different length as first challenge of our predictions. Experimental results confirmed that the 12 residue long peptide is necessary and sufficient to induce membrane destabilization to the same extent as the 23 residue long fusion peptide. In silico analysis of some fusion-incompetent mutants presented in the literature further revealed that they cannot insert into a modelled membrane correctly tilted. According to this work, the tilted peptide model appears to explain at least partly the membrane destabilization properties of HIV fusion peptide.
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Affiliation(s)
- B Charloteaux
- Centre de Biophysique Moléculaire Numérique, Faculté Universitaire des Sciences Agronomiques, Passage des déportés, B-5030 Gembloux, Belgium.
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31
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Lins L, Charloteaux B, Heinen C, Thomas A, Brasseur R. "De novo" design of peptides with specific lipid-binding properties. Biophys J 2006; 90:470-9. [PMID: 16275638 PMCID: PMC1367053 DOI: 10.1529/biophysj.105.068213] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2005] [Accepted: 09/13/2005] [Indexed: 11/18/2022] Open
Abstract
In this study, we describe an in silico method to design peptides that can be made of non-natural amino acids and elicit specific membrane-interacting properties. The originality of the method holds in the capacities developed to design peptides from any non-natural amino acids as easily as from natural ones, and to test the structure stability by an angular dynamics rather than the currently-used molecular dynamics. The goal of this study was to design a non-natural tilted peptide. Tilted peptides are short protein fragments able to destabilize lipid membranes and characterized by an asymmetric distribution of hydrophobic residues along their helix structure axis. The method is based on the random generation of peptides and their selection on three main criteria: mean hydrophobicity and the presence of at least one polar residue; tilted insertion at the level of the acyl chains of lipids of a membrane; and conformational stability in that hydrophobic phase. From 10,000,000 randomly-generated peptides, four met all the criteria. One was synthesized and tested for its lipid-destabilizing properties. Biophysical assays showed that the "de novo" peptide made of non-natural amino acids is helical either in solution or into lipids as tested by Fourier transform infrared spectroscopy and is able to induce liposome fusion. These results are in agreement with the calculations and validate the theoretical approach.
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Affiliation(s)
- L Lins
- Centre de Biophysique Moléculaire Numérique, Faculté des Sciences Agronomiques de Gembloux, Gembloux, Belgium
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32
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Adam B, Lins L, Stroobant V, Thomas A, Brasseur R. Distribution of hydrophobic residues is crucial for the fusogenic properties of the Ebola virus GP2 fusion peptide. J Virol 2004; 78:2131-6. [PMID: 14747578 PMCID: PMC369453 DOI: 10.1128/jvi.78.4.2131-2136.2004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2003] [Accepted: 11/04/2003] [Indexed: 11/20/2022] Open
Abstract
The lipid-destabilizing properties of the N-terminal domain of the GP2 of Ebola virus were investigated. Our results suggest that the domain of Ebola virus needed for fusion is shorter than that previously reported. The fusogenic properties of this domain are related to its oblique orientation at the lipid/water interface owing to an asymmetric distribution of the hydrophobic residues when helical.
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Affiliation(s)
- B Adam
- Centre de Biophysique Moléculaire Numérique, FSAGX, 5030 Gembloux, Leuven, Belgium
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33
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Lins L, Flore C, Chapelle L, Talmud PJ, Thomas A, Brasseur R. Lipid-interacting properties of the N-terminal domain of human apolipoprotein C-III. Protein Eng Des Sel 2002; 15:513-20. [PMID: 12082170 DOI: 10.1093/protein/15.6.513] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [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: 11/14/2022] Open
Abstract
The lipid-interacting properties of the N-terminal domain of human apolipoprotein C-III (apo C-III) were investigated. By molecular modeling, we predicted that the 6-20 fragment of apo C-III is obliquely orientated at the lipid/water interface owing to an asymmetric distribution of the hydrophobic residues when helical. This is characteristic of 'tilted peptides' originally discovered in viral fusion proteins and later in various proteins including some involved in lipoprotein metabolism. Since most tilted peptides were shown to induce liposome fusion in vitro, the fusogenic capacity of the 6-20 fragment of apo C-III was tested on unilamellar liposomes and compared with the well characterized SIV fusion peptide. Mutants were designed by molecular modeling to assess the role of the hydrophobicity gradient in the fusion. FTIR spectroscopy confirmed the predominantly helical conformation of the peptides in TFE solution and also in lipid-peptide complexes. Lipid-mixing experiments showed that the apo C-III (6-20) peptide is able to increase the fluorescence of a lipophilic fluorescent probe. The vesicle fusion was confirmed by core-mixing and leakage assays. The hydrophobicity gradient plays a key role in the fusion process because the mutant with no hydrophobic asymmetry but the same mean hydrophobicity as the wild type does not induce significant lipid fusion. The apo C-III (6-20) fragment is, however, less fusogenic than the SIV peptide, in agreement with their respective mean hydrophobicity. Since lipid fusion should not be the physiological function of the N-terminal domain of apo CIII, we suggest that its peculiar distribution of hydrophobic residues is important for the lipid-binding properties of apo C-III and should be involved in apolipoprotein and lipid exchanges crucial for triglyceride metabolism.
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Affiliation(s)
- L Lins
- INSERM U447, IBL, 59021 Lille Cedex, France
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34
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Lins L, Charloteaux B, Thomas A, Brasseur R. Computational study of lipid-destabilizing protein fragments: towards a comprehensive view of tilted peptides. Proteins 2001; 44:435-47. [PMID: 11484221 DOI: 10.1002/prot.1109] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [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: 11/11/2022]
Abstract
Tilted peptides are short sequence fragments (10-20 residues long) that possess an asymmetric hydrophobicity gradient along their sequence when they are helical. Due to this gradient, they adopt a tilted orientation towards a single lipid/water interface and destabilize the lipids. We have detected those peptides in many different proteins with various functions. While being all tilted-oriented at a single lipid/water interface, no consensus sequence can be evidenced. In order to better understand the relationships between their lipid-destabilizing activity and their properties, we used IMPALA to classify the tilted peptides. This method allows the study of interactions between a peptide and a modeled lipid bilayer using simple restraint functions designed to mimic some of the membrane properties. We predict that tilted peptides have access to a wide conformational space in membranes, in contrast to transmembrane and amphipathic helices. In agreement with previous studies, we suggest that those metastable configurations could lead to the perturbation of the acyl chains organization and could be a general mechanism for lipid destabilization. Our results further suggest that tilted peptides fall into two classes: those from proteins acting on membrane behave differently than destabilizing fragments from interfacial proteins. While the former have equal access to the two layers of the membrane, the latter are confined within a single lipid layer. This could be in relation with the organization of lipid substrate on which the peptides physiologically act.
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Affiliation(s)
- L Lins
- INSERM U410, Faculté X. Bichat, Paris, France
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35
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Messika-Zeitoun L, Gouédard L, Belville C, Dutertre M, Lins L, Imbeaud S, Hughes IA, Picard JY, Josso N, di Clemente N. Autosomal recessive segregation of a truncating mutation of anti-Müllerian type II receptor in a family affected by the persistent Müllerian duct syndrome contrasts with its dominant negative activity in vitro. J Clin Endocrinol Metab 2001; 86:4390-7. [PMID: 11549681 DOI: 10.1210/jcem.86.9.7839] [Citation(s) in RCA: 6] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Anti-Müllerian hormone belongs to the TGFbeta family whose members exert their effects by signaling through two related serine/threonine kinase receptors. Mutations of the anti-Müllerian hormone type II receptor occur naturally, causing the persistent Müllerian duct syndrome. In a family with two members with persistent Müllerian duct syndrome and one normal sibling, we detected two novel mutations of the anti-Müllerian hormone type II receptor gene. One, transmitted by the mother to her three sons, is a deletion of a single base leading to a stop codon, causing receptor truncation after the transmembrane domain. The other, a missense mutation in the substrate-binding site of the kinase domain, is transmitted by the father to the two sons affected by persistent Müllerian duct syndrome, indicating a recessive autosomal transmission as in other cases of persistent Müllerian duct syndrome. Truncating mutations in receptors of the TGFbeta family exert dominant negative activity, which was seen only when each of the mutant anti-Müllerian hormone receptors was overexpressed in an anti-Müllerian hormone-responsive cell line. We conclude that assessment of dominant activity in vitro, which usually involves overexpression of mutant genes, does not necessarily produce information applicable to clinical conditions, in which mutant and endogenous genes are expressed on a one to one basis.
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Affiliation(s)
- L Messika-Zeitoun
- Unité de Recherches sur l'Endocrinologie du Développement, INSERM, U-493, Département de Biologie, Ecole Normale Supérieure, 92120 Montrouge, France
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36
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Festy F, Lins L, Péranzi G, Octave JN, Brasseur R, Thomas A. Is aggregation of beta-amyloid peptides a mis-functioning of a current interaction process? Biochim Biophys Acta 2001; 1546:356-64. [PMID: 11295441 DOI: 10.1016/s0167-4838(01)00158-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
In a previous study, Hughes et al. [Proc. Natl. Acad. Sci. USA 93 (1996) 2065-2070] demonstrated that the amyloid peptide is able to interact with itself in a two-hybrid system and that interaction is specific. They further supported that the method could be used to define the sequences that might be important in nucleation-dependent aggregation. The sequence of the amyloid peptide can be split into four clusters, two hydrophilic (1-16 and 22-28) and two hydrophobic (17-21 and 29-42). We designed by molecular modeling and tested by the two-hybrid approach, series of mutations spread all over the sequence and changing the distribution of hydrophobicity and/or the spatial hindrance. In the two-hybrid assay, interaction of native Abeta is reproduced. Screening of mutations demonstrates that the C-domain (residues 29-40 (42)), the median domain (residues 17-22) and the N-domain (1-16) are all crucial for interaction. This demonstrates that almost all fragments of the amyloid peptide but a loop (residues 23-28) and the C-term amino acid are important for the native interaction. We support that the folded three-dimensional (3D) structure is the Abeta-Abeta interacting species, that the whole sequence is involved in that 3D fold which has a low secondary structure propensity and a high susceptibility to mutations and thus should have a low stability. The native fold of Abeta could be stabilized in Abeta-Abeta complexes which could in other circumstances facilitate the nucleation event of aggregation that leads to the formation of stable senile plaques.
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Affiliation(s)
- F Festy
- INSERM U410, Faculté X. Bichat, 75870 Paris Cedex 18, France
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37
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Lins L, Couvineau A, Rouyer-Fessard C, Nicole P, Maoret JJ, Benhamed M, Brasseur R, Thomas A, Laburthe M. The human VPAC1 receptor: three-dimensional model and mutagenesis of the N-terminal domain. J Biol Chem 2001; 276:10153-60. [PMID: 11124960 DOI: 10.1074/jbc.m009730200] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [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: 02/05/2023] Open
Abstract
The human VPAC(1) receptor for vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase activating peptide belongs to the class II family of G-protein-coupled receptors with seven transmembrane segments. Like for all class II receptors, the extracellular N-terminal domain of the human VPAC(1) receptor plays a predominant role in peptide ligand recognition. To determine the three-dimensional structure of this N-terminal domain (residues 1-144), the Protein Data Bank (PDB) was screened for a homologous protein. A subdomain of yeast lipase B was found to have 27% sequence identity and 50% sequence homology with the N-terminal domain (8) of the VPAC(1) receptor together with a good alignment of the hydrophobic clusters. A model of the N-terminal domain of VPAC(1) receptor was thus constructed by homology. It indicated the presence of a putative signal sequence in the N-terminal extremity. Moreover, residues (Glu(36), Trp(67), Asp(68), Trp(73), and Gly(109)) which were shown to be crucial for VIP binding are gathered around a groove that is essentially negatively charged. New putatively important residues for VIP binding were suggested from the model analysis. Site-directed mutagenesis and stable transfection of mutants in CHO cells indicated that Pro(74), Pro(87), Phe(90), and Trp(110) are indeed important for VIP binding and activation of adenylyl cyclase activation. Combination of molecular modeling and directed mutagenesis provided the first partial three-dimensional structure of a VIP-binding domain, constituted of an electronegative groove with an outspanning tryptophan shell at one end, in the N-terminal extracellular region of the human VPAC(1) receptor.
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MESH Headings
- Adenylyl Cyclases/metabolism
- Amino Acid Sequence
- Animals
- CHO Cells
- Cricetinae
- DNA, Complementary/metabolism
- Databases, Factual
- Enzyme Activation
- Epitopes
- Humans
- Kinetics
- Ligands
- Microscopy, Fluorescence
- Models, Molecular
- Molecular Sequence Data
- Mutagenesis
- Mutagenesis, Site-Directed
- Mutation
- Phenotype
- Protein Binding
- Protein Structure, Secondary
- Protein Structure, Tertiary
- Receptors, Vasoactive Intestinal Peptide/chemistry
- Receptors, Vasoactive Intestinal Polypeptide, Type I
- Sequence Homology, Amino Acid
- Signal Transduction
- Software
- Structure-Activity Relationship
- Transfection
- Tryptophan/metabolism
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Affiliation(s)
- L Lins
- Unité INSERM U410 de Neuroendocrinologie et Biologie Cellulaire Digestives, Institut National de la Santé et de la Recherche Médicale, Faculté de Médecine Xavier Bichat, Paris F-75018, France
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38
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Haïk S, Peyrin JM, Lins L, Rosseneu MY, Brasseur R, Langeveld JP, Tagliavini F, Deslys JP, Lasmézas C, Dormont D. Neurotoxicity of the putative transmembrane domain of the prion protein. Neurobiol Dis 2000; 7:644-56. [PMID: 11114262 DOI: 10.1006/nbdi.2000.0316] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [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: 11/22/2022] Open
Abstract
It has been shown recently that the generation of an abnormal transmembrane form of the prion protein ((Ctm)PrP) is involved in the neurodegeneration process during inherited and infectious prion diseases but a causative relationship has never been established. We wanted to know if and how the proposed transmembrane domain of PrP could induce neuronal dysfunction. Thus, we investigated the neurotoxic properties of two peptides whose sequences are encompassed within this domain. We show that PrP peptides 118-135 and 105-132 as well as an amidated more soluble peptide 105-132 induce the death of pure cortical neurons originating from normal and PrP knockout mice. This can be correlated with the high propensity of these peptides to insert stably into and to destabilize cell membranes. Through this study, we have identified a novel mechanism of neurotoxicity for PrP, which directly involves membrane perturbation; this mechanism is independent of fibril formation and probably corresponds to the effect of the transmembrane insertion of (Ctm)PrP.
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Affiliation(s)
- S Haïk
- CEA, Fontenay aux Roses Cedex, 92 265, France
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39
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Liu H, Labeur C, Xu CF, Ferrell R, Lins L, Brasseur R, Rosseneu M, Weiss KM, Humphries SE, Talmud PJ. Characterization of the lipid-binding properties and lipoprotein lipase inhibition of a novel apolipoprotein C-III variant Ala23Thr. J Lipid Res 2000; 41:1760-71. [PMID: 11060345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
We have identified a G-to-A transition in exon 3 of the APOC3 gene resulting in a novel Ala23Thr apolipoprotein (apo) C-III variant, associated with apoC-III deficiency in three unrelated Yucatan Indians. The Ala23Thr substitution modifies the hydrophobic/hydrophilic repartition of the helical N-terminal peptide and hence could disturb the lipid association. In vitro expression in Escherichia coli of wild-type and mutant apoC-III enabled the characterization of the variant. Compared with wild-type apoC-III-Ala23, the mutant apoC-III-Thr23 showed reduced affinity for dimyristoylphosphatidylcholine (DMPC) multilamellar vesicles with higher amounts of free apoC-III. Displacement of apoE from discoidal apoE:dipalmitoylphosphatidycholine (DPPC) complex by apoC-III-Thr23 was comparable to wild type but the less efficient binding of the apoC-III-Thr23 to the discoidal complex resulted in a higher apoE/apoC-III (mol/mol) ratio (34%) than with wild-type/apoE:DPPC mixtures. The inhibition of lipoprotein lipase (LPL) by apoC-III-Thr23 was comparable to that of wild type, and therefore effects on LPL activity could not explain the lower triglyceride (Tg) levels in Thr-23 carriers. Thus, these in vitro results suggest that in vivo the less efficient lipid binding of apoC-III-Thr23 might lead to a faster catabolism of free apoC-III, reflected in the reduced plasma apoC-III levels identified in Thr-23 carriers, and poorer competition with apoE, which might enhance clearance of Tg-rich lipoproteins and lower plasma Tg levels seen in Thr-23 carriers.
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Affiliation(s)
- H Liu
- Cardiovascular Genetics Division, Department of Medicine, Royal Free and University College London Medical School, London WC1E 6JJ, UK
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40
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Liu H, Talmud PJ, Lins L, Brasseur R, Olivecrona G, Peelman F, Vandekerckhove J, Rosseneu M, Labeur C. Characterization of recombinant wild type and site-directed mutations of apolipoprotein C-III: lipid binding, displacement of ApoE, and inhibition of lipoprotein lipase. Biochemistry 2000; 39:9201-12. [PMID: 10924113 DOI: 10.1021/bi0009441] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [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
The physicochemical properties of recombinant wild type and three site-directed mutants of apolipoprotein C-III (apoC-III), designed by molecular modeling to alter specific amino acid residues implicated in lipid binding (L9T/T20L, F64A/W65A) or LPL inhibition (K21A), were compared. Relative lipid binding efficiencies to dimyristoylphosphatidylcholine (DMPC) were L9T/T20L > WT >K21A > F64A/W65A with an inverse correlation with size of the discoidal complexes formed. Physicochemical analysis (Trp fluorescence, circular dichroism, and GdnHCl denaturation) suggests that L9T/T20L forms tighter and more stable lipid complexes with phospholipids, while F64A/W65A associates less tightly. Lipid displacement properties were tested by gel-filtrating apoE:dipalmitoylphosphatidylcholine (DPPC) discoidal complexes mixed with the various apoC-III variants. All apoC-III proteins bound to the apoE:DPPC complexes; the amount of apoE displaced from the complex was dependent on the apoC-III lipid binding affinity. All apoC-III proteins inhibited LPL in the presence or absence of apoC-II, with F64A/W65A displaying the most inhibition, suggesting that apoC-III inhibition of LPL is independent of lipid binding and therefore of apoC-II displacement. Taken together. these data suggest that the hydrophobic residues F64 and W65 are crucial for the lipid binding properties of apoC-III and that redistribution of the N-terminal helix of apoC-III (L9T/T20L) enhances the stability of the lipid-bound protein, while LPL inhibition by apoC-III is likely to be due to protein:protein interactions.
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Affiliation(s)
- H Liu
- Centre for Cardiovascular Genetics, Department of Medicine, Royal Free and University College, London Medical School
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41
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Nicole P, Lins L, Rouyer-Fessard C, Drouot C, Fulcrand P, Thomas A, Couvineau A, Martinez J, Brasseur R, Laburthe M. Identification of key residues for interaction of vasoactive intestinal peptide with human VPAC1 and VPAC2 receptors and development of a highly selective VPAC1 receptor agonist. Alanine scanning and molecular modeling of the peptide. J Biol Chem 2000; 275:24003-12. [PMID: 10801840 DOI: 10.1074/jbc.m002325200] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.2] [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: 02/05/2023] Open
Abstract
The widespread neuropeptide vasoactive intestinal peptide (VIP) has two receptors VPAC(1) and VPAC(2). Solid-phase syntheses of VIP analogs in which each amino acid has been changed to alanine (Ala scan) or glycine was achieved and each analog was tested for: (i) three-dimensional structure by ab initio molecular modeling; (ii) ability to inhibit (125)I-VIP binding (K(i)) and to stimulate adenylyl cyclase activity (EC(50)) in membranes from cell clones stably expressing human recombinant VPAC(1) or VPAC(2) receptor. The data show that substituting residues at 14 positions out of 28 in VIP resulted in a >10-fold increase of K(i) or EC(50) at the VPAC(1) receptor. Modeling of the three-dimensional structure of native VIP (central alpha-helice from Val(5) to Asn(24) with random coiled N and C terminus) and analogs shows that substitutions of His(1), Val(5), Arg(14), Lys(15), Lys(21), Leu(23), and Ile(26) decreased biological activity without altering the predicted structure, supporting that those residues directly interact with VPAC(1) receptor. The interaction of the analogs with human VPAC(2) receptor is similar to that observed with VPAC(1) receptor, with three remarkable exceptions: substitution of Thr(11) and Asn(28) by alanine increased K(i) for binding to VPAC(2) receptor; substitution of Tyr(22) by alanine increased EC(50) for stimulating adenylyl cyclase activity through interaction with the VPAC(2) receptor. By combining 3 mutations at positions 11, 22, and 28, we developed the [Ala(11,22,28)]VIP analog which constitutes the first highly selective (>1,000-fold) human VPAC(1) receptor agonist derived from VIP ever described.
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Affiliation(s)
- P Nicole
- Unité INSERM U410 de Neuroendocrinologie et Biologie Cellulaire Digestives, Faculté de Médecine Xavier Bichat, Paris, 75018, France
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Labeur C, Liu H, Lins L, Brasseur R, Rosseneu M, Olivecrona G, Humphries S, Talmud P. Lipid binding and LPL inhibition properties of N- AND C-terminal mutants of human APO C-III. Atherosclerosis 2000. [DOI: 10.1016/s0021-9150(00)80853-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Abstract
Nisin is a 34-residue lantibiotic widely used as food preservative. Its mode of action on the bacterial cytoplasmic membrane is unclear. It should form ion channels but a molecular description of the interaction between nisin and phospholipids is lacking. The interactions between nisin and a membrane and the influence of phospholipids are here analysed by molecular modelling. The NMR structures of nisin in a micellar environment were previously determined (Van den Hooven et al., Eur. J. Biochem. 235 (1996) 382-393) Those structures were used to start with. They were refined by running a Monte Carlo procedure at a model lipid/water interface. It was shown that nisin is adsorbing onto the interface, with its N-terminal moiety more deeply inserted in lipids than the C-end, indicating distinct hydrophobic properties of the N- and C-domains. Therefore, we suggest that the N-terminal part is implied in the insertion of nisin in lipids, while the C-terminal moiety could be involved in the initial interaction with the membrane surface. Modelling the interaction of nisin with different neutral or anionic phospholipids shows that it disturbs the lipid organisation. The disturbance is maximal with phosphatidylglycerol. In this system, nisin curves the surface of phosphatidylglycerol layer round suggesting it could induce micelle formation. This could be a preliminary step to pore formation. It suggests that phosphatidylglycerol could have a direct action on nisin insertion and on ion channel formation. Appearance of a curvature also agrees with the 'wedge model' proposed in the literature for the nisin pore formation.
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Affiliation(s)
- L Lins
- INSERM U10, Hôpital Bichat, 170 bd Ney, 75018, Paris, France
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Lins L, Thomas-Soumarmon A, Pillot T, Vandekerchkhove J, Rosseneu M, Brasseur R. Molecular determinants of the interaction between the C-terminal domain of Alzheimer's beta-amyloid peptide and apolipoprotein E alpha-helices. J Neurochem 1999; 73:758-69. [PMID: 10428074 DOI: 10.1046/j.1471-4159.1999.0730758.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [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: 11/20/2022]
Abstract
In a previous work, we predicted and demonstrated that the 29-42-residue fragment of beta-amyloid peptide (Abeta peptide) has in vitro capacities close to those of the tilted fragment of viral fusion proteins. We further demonstrated that apolipoprotein E2 and E3 but not apolipoprotein E4 can decrease the fusogenic activity of Abeta(29-42) via a direct interaction. Therefore, we suggested that this fragment is implicated in the neurotoxicity of Abeta and in the protective effects of apolipoprotein E in Alzheimer's disease. Because structurally related apolipoproteins do not interact with the Abeta C-terminal domain but inhibit viral fusion, we suggested that interactions existing between fusogenic peptides and apolipoproteins are selective and responsible for the inhibition of fusion. In this study, we simulated interactions of all amphipathic helices of apolipoproteins E and A-I with Abeta and simian immunodeficiency virus (SIV) fusogenic fragments by molecular modeling. We further calculated cross-interactions that do not inhibit fusion in vitro. The results suggest that interactions of hydrophobic residues are the major event to inhibit the fusogenic capacities of Abeta(29-42) and SIV peptides. Selectivity of those interactions is due to the steric complementarity between bulky hydrophobic residues in the fusogenic fragments and hydrophobic residues in the apolipoprotein C-terminal amphipathic helices.
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Affiliation(s)
- L Lins
- INSERM U. 10, Hôpital Bichat-Claude Bernard, Paris, France
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Peuvot J, Schanck A, Lins L, Brasseur R. Are the fusion processes involved in birth, life and death of the cell depending on tilted insertion of peptides into membranes? J Theor Biol 1999; 198:173-81. [PMID: 10339392 DOI: 10.1006/jtbi.1999.0908] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [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: 11/22/2022]
Abstract
Various peptide segments have been modeled as asymmetric amphipathic alpha-helices. Theoretical calculations have shown that they insert obliquely into model membranes. They have been named "tilted peptides". Molecular modeling results reported here also evidence the presence of tilted peptides in ADM-1 protein of Caenorhabditis elegans that may be involved in fusion events, in meltrin alpha, a protein implicated in myoblast fusion, in hemagglutinin of influenza virus, in the E2 glycoprotein of rubella virus, in the S protein of hepatitis B virus, in a subdomain of Ebola virus and in the malaria CS protein. Experimental results have indicated that tilted peptide fragments may be involved in cellular life events like sperm-egg fecondation, muscle development, protein translocation through signal sequences and cellular death caused by viral infection or parasite infestation. We speculate that membrane destabilization by these tilted peptides may be an important common step in life processes involving fusion phenomena.
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Affiliation(s)
- J Peuvot
- Medical Affairs, UCB-Pharma, allée de la Recherche, 1070 Bruxelles, Belgium.
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Pillot T, Goethals M, Najib J, Labeur C, Lins L, Chambaz J, Brasseur R, Vandekerckhove J, Rosseneu M. Beta-amyloid peptide interacts specifically with the carboxy-terminal domain of human apolipoprotein E: relevance to Alzheimer's disease. J Neurochem 1999; 72:230-7. [PMID: 9886074 DOI: 10.1046/j.1471-4159.1999.0720230.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.7] [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: 11/20/2022]
Abstract
Growing evidence indicates the involvement of apolipoprotein E (apoE) in the development of late-onset and sporadic forms of Alzheimer's disease, although its exact role remains unclear. We previously demonstrated that beta-amyloid peptide (Abeta) displays membrane-destabilizing properties and that only apoE2 and E3 isoforms inhibit these properties. In this study, we clearly demonstrate that the carboxy-terminal lipid-binding domain of apoE (e.g., residues 200-299) is responsible for the Abeta-binding activity of apoE and that this interaction involves pairs of apoE amphipathic alpha-helices. We further demonstrate that Abeta is able to inhibit the association of the C-terminal domain of apoE with lipids due to the formation of Abeta/apoE complexes resistant to sodium dodecyl sulfate-polyacrylamide gel electrophoresis. On the contrary, the amino-terminal receptor-binding domain of apoE (e.g., residues 129-169) is not able to form stable complexes with Abeta. These data extend our understanding of human apoE-dependent binding of Abeta by involving the C-terminal domain of apoE in the efficient formation of apoE/Abeta complex.
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Affiliation(s)
- T Pillot
- Laboratory for Lipoprotein Chemistry, University of Gent, Belgium
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Festy F, Lins L, Gallet X, Robert JC, Thomas-Soumarmon A. 1-anilino-8-naphtalene sulfonate probes a gastric HK-ATPase potassium site whose access requires ionophores. J Membr Biol 1998; 165:153-60. [PMID: 9745003 DOI: 10.1007/s002329900429] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [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: 11/27/2022]
Abstract
1-anilino-8-naphtalenesulfonate (ANS) is a hydrophobic dipole previously used to demonstrate that the proton for potassium exchange by the gastric HK-ATPase is electroneutral. In this paper, we demonstrate that ANS binds to gastric membranes and probes conformational changes of the HK-ATPase independently of any active H for K exchange. Conformational changes require the presence of potassium-valinomycin and are not triggered by sodium. Potassium effect is enhanced by ATP, in the presence and in the absence of magnesium and, by ADP, in the presence of magnesium. Labeling of the pig HK-ATPase K518 by fluorescein-5-isothiocyanate inhibits the enzyme activity and knocks out the ATP effect on ANS fluorescence. Scherring 28080 and the monoclonal antibody 95-111, two competitive inhibitors of K-activated ATPase dephosphorylation, do not modify K-effect on ANS fluorescence but inhibit ATP effects. This supports that ANS does not probe K-site between the H1-H2 loop. Treatment of gastric membranes with trypsin does not inhibit the ANS response to potassium but does inhibit the response to ATP. This suggests that the ATP site inducing the ANS response is cytoplasmic and the potassium site is intramembranous. Titration reveals that one mole of ANS interacts with one mole of ATPase. We suggest that ANS probes a hydrophobic potassium site of gastric ATPase and that addition of ATP and ADP-Mg embed that site.
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Affiliation(s)
- F Festy
- INSERM U10, Hôpital Bichat, Paris, France
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Pillot T, Lins L, Goethals M, Vanloo B, Baert J, Vandekerckhove J, Rosseneu M, Brasseur R. The 118-135 peptide of the human prion protein forms amyloid fibrils and induces liposome fusion. J Mol Biol 1997; 274:381-93. [PMID: 9405147 DOI: 10.1006/jmbi.1997.1382] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.6] [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: 02/05/2023]
Abstract
The prion protein (PrPC) is a glycoprotein of unknown function normally found at the surface of neurons and of glial cells. It is involved in diseases such as bovine spongiform encephalopathy, and Creutzfeldt-Jakob disease in the human, where PrPC is converted into an altered form (termed PrPSc). PrPSc is highly resistant towards proteolytic degradation and accumulates in the central nervous system of affected individuals. By analogy with the pathological events occuring during the development of Alzheimer's disease, controverses still exist regarding the relationship between amyloidogenesis, prion aggregation and neuronal loss. To unravel the mechanism of PrP neurotoxicity and understand the interaction of PrP with cellular membranes, a series of natural and variant peptides spanning residues 118 to 135 of PrP was synthesized. The potential of these peptides to induce fusion of unilamellar lipid vesicles was investigated. According to computer modeling calculations, the 120 to 133 domain of PrP is predicted to be a tilted lipid-associating peptide, and to insert in a oblique way into a lipid bilayer through its N-terminal end. In addition to amyloidogenic properties exhibited in vitro by these peptides, peptide-induced vesicle fusion was demonstrated by several techniques, including lipid- and core-mixing assays. Elongation of the 120 to 133 peptide towards the N- and C-terminal ends of the PrP sequence showed that the 118 to 135 PrP peptide has maximal fusogenic properties, while the variant peptides had no effect. Due to their high hydrophobicity, all peptides tested were able to interact with liposomes to induce leakage of encapsulated calcein. We demonstrate also that the propensity of the peptides to fold as an alpha-helix increases their fusogenic activity, thus accounting for the maximal fusogenic activity of the most stable helix at residues 118 to 135. These data suggest that, by analogy with the C-terminal domain of the beta-amyloid peptide, the fusogenic properties exhibited by the prion peptides might contribute to the neurotoxicity of these peptides by destabilizing cellular membranes.
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Affiliation(s)
- T Pillot
- Department of Biochemistry, Universiteit Gent, Belgium
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Pillot T, Lins L, Najib J, Brasseur R, Rosseneu M. 4.P.389 Interaction of human apoE with the fusogenic C-terminal Alzheimer's β-amyloid peptide is mediated by the lipid-binding domain of apoE. Atherosclerosis 1997. [DOI: 10.1016/s0021-9150(97)89917-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Abstract
This review describes a class of peptides that associate with lipids in membranes and are commonly known as 'oblique-orientated peptides'. Owing to an asymmetric distribution of hydrophobic residues along the axis of the alpha-helix, such peptides can destabilize membranes or lipid cores, thereby facilitating such cellular processes as vesicular fusion or protein transport across subcellular compartments, as well as remodelling of lipid cores.
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Affiliation(s)
- R Brasseur
- Centre Biophysique Moleculaire Numerique, Fac. Agronomiques, Gembloux, Belgium
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