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Hayakawa ESH, Ueki M, Alhatmi E, Oiki S, Tokumasu F, Mitchell DC, Iwamoto M. Different lateral packing stress in acyl chains alters KcsA orientation and structure in lipid membranes. Biochim Biophys Acta Biomembr 2024:184338. [PMID: 38763269 DOI: 10.1016/j.bbamem.2024.184338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 04/26/2024] [Accepted: 05/12/2024] [Indexed: 05/21/2024]
Abstract
The molecular structures of the various intrinsic lipids in membranes regulate lipid-protein interactions. These different lipid structures with unique volumes produce different lipid molecular packing stresses/lateral stresses in lipid membranes. Most studies examining lipid packing effects have used phosphatidylcholine and phosphatidylethanolamine (PE), which are the main phospholipids of eukaryotic cell membranes. In contrast, Gram-negative or Gram-positive bacterial membranes are composed primarily of phosphatidylglycerol (PG) and PE, and the physical and thermodynamic properties of each acyl chain in PG at the molecular level remain unresolved. In this study, we used 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (POPG, 16:0-18:1 PG) and 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (PAPG, 16:0-20:4 PG) to prepare lipid bilayers (liposome) with the rod-type fluorescence probe DPH. We measured the lipid packing conditions by determining the rotational freedom of DPH in POPG or PAPG bilayers. Furthermore, we investigated the effect of different monoacyl chains on a K+ channel (KcsA) structure when embedded in POPG or PAPG membranes. The results revealed that differences in the number of double bonds and carbon chain length in the monoacyl chain at sn-2 affected the physicochemical properties of the membrane and the structure and orientation of KcsA.
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Affiliation(s)
- Eri Saki H Hayakawa
- Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan.
| | - Misuzu Ueki
- Division of Molecular Neuroscience, Faculty of Medical Sciences, University of Fukui, 23-3 Matsuoka Shimoaizuki, Eiheiji-cho, Yoshida-gun, Fukui 910-1193, Japan
| | - Elmukhtar Alhatmi
- Department of Physics, Portland State University, Portland, OR 97201-0751, USA
| | - Shigetoshi Oiki
- Biomedical Imaging Research Center, University of Fukui, 23-3 Matsuoka Shimoaizuki, Eiheiji-cho, Yoshida-gun, Fukui 9101193, Japan
| | - Fuyuki Tokumasu
- Department of Cellular Architecture Studies, Division of Shionogi Global Infectious Diseases, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; School of Tropical Medicine and Global Health, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; Department of Laboratory Sciences, Graduate School of Health Sciences, Gunma University, 3-39-22 Showa-machi, Maebashi, Gunma 371-8514, Japan
| | - Drake C Mitchell
- Department of Physics, Portland State University, Portland, OR 97201-0751, USA
| | - Masayuki Iwamoto
- Division of Molecular Neuroscience, Faculty of Medical Sciences, University of Fukui, 23-3 Matsuoka Shimoaizuki, Eiheiji-cho, Yoshida-gun, Fukui 910-1193, Japan
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Yasuda T, Ueura D, Nakagomi M, Hanashima S, Peter Slotte J, Murata M. Design, synthesis of ceramide 1-phosphate analogs and their affinity for cytosolic phospholipase A 2 as evidenced by surface plasmon resonance. Bioorg Med Chem Lett 2024; 107:129792. [PMID: 38734389 DOI: 10.1016/j.bmcl.2024.129792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2024] [Revised: 05/06/2024] [Accepted: 05/08/2024] [Indexed: 05/13/2024]
Abstract
Ceramide 1-phosphate (C1P) is a lipid mediator that specifically binds and activates cytosolic phospholipase A2α (cPLA2α). To elucidate the structure-activity relationship of the affinity of C1P for cPLA2α in lipid environments, we prepared a series of C1P analogs containing structural modifications in the hydrophilic parts and subjected them to surface plasmon resonance (SPR). The results suggested the presence of a specific binding site for cPLA2α on the amide, 3-OH and phosphate groups in C1P structure. Especially, dihydro-C1P exhibited enhanced affinity for cPLA2α, suggesting the hydrogen bonding ability of 3-hydroxy group is important for interactions with cPLA2α. This study helps to understand the influence of specific structural moieties of C1P on the interaction with cPLA2α at the atomistic level and may lead to the design of drugs that regulate cPLA2α activation.
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Affiliation(s)
- Tomokazu Yasuda
- Research Foundation ITSUU Laboratory, C1232, Kanagawa Science Park R&D Building, 3-2-1 Sakado, Takatsu-ku, Kawasaki, Kanagawa 213-0012, Japan; Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan; Forefront Research Center, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.
| | - Daiki Ueura
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - Madoka Nakagomi
- Research Foundation ITSUU Laboratory, C1232, Kanagawa Science Park R&D Building, 3-2-1 Sakado, Takatsu-ku, Kawasaki, Kanagawa 213-0012, Japan
| | - Shinya Hanashima
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - J Peter Slotte
- Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Tykistökatu 6A, FIN-20520 Turku, Finland
| | - Michio Murata
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan; Forefront Research Center, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
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3
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Ohkubo YZ, Radulovic PW, Kahira AN, Madsen JJ. Membrane binding and lipid-protein interaction of the C2 domain from coagulation factor V. Curr Res Struct Biol 2024; 7:100149. [PMID: 38766652 PMCID: PMC11098723 DOI: 10.1016/j.crstbi.2024.100149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 03/28/2024] [Accepted: 04/29/2024] [Indexed: 05/22/2024] Open
Abstract
Anchoring of coagulation factors to anionic regions of the membrane involves the C2 domain as a key player. The rate of enzymatic reactions of the coagulation factors is increased by several orders of magnitude upon membrane binding. However, the precise mechanisms behind the rate acceleration remain unclear, primarily because of a lack of understanding of the conformational dynamics of the C2-containing factors and corresponding complexes. We elucidate the membrane-bound form of the C2 domain from human coagulation factor V (FV-C2) by characterizing its membrane binding the specific lipid-protein interactions. Employing all-atom molecular dynamics simulations and leveraging the highly mobile membrane-mimetic (HMMM) model, we observed spontaneous binding of FV-C2 to a phosphatidylserine (PS)-containing membrane within 2-25 ns across twelve independent simulations. FV-C2 interacted with the membrane through three loops (spikes 1-3), achieving a converged, stable orientation. Multiple HMMM trajectories of the spontaneous membrane binding provided extensive sampling and ample data to examine the membrane-induced effects on the conformational dynamics of C2 as well as specific lipid-protein interactions. Despite existing crystal structures representing presumed "open" and "closed" states of FV-C2, our results revealed a continuous distribution of structures between these states, with the most populated structures differing from both "open" and "closed" states observed in crystal environments. Lastly, we characterized a putative PS-specific binding site formed by K23, Q48, and S78 located in the groove enclosed by spikes 1-3 (PS-specificity pocket), suggesting a different orientation of a bound headgroup moiety compared to previous proposals based upon analysis of static crystal structures.
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Affiliation(s)
- Y. Zenmei Ohkubo
- Department of Bioinformatics, School of Life and Natural Sciences, Abdullah Gül University, Kayseri, Turkey
| | - Peter W. Radulovic
- Graduate Programs, Taneja College of Pharmacy, University of South Florida, Tampa, FL 33612, USA
| | - Albert N. Kahira
- Graduate Programs, School of Engineering, Abdullah Gül University, Kayseri, Turkey
| | - Jesper J. Madsen
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
- Center for Global Health and Infectious Diseases Research, Global and Planetary Health, College of Public Health, University of South Florida, Tampa, FL 33612, USA
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Abstract
Lipid-protein interactions are normally classified as either specific or general. Specific interactions refer to lipid binding to specific binding sites within a membrane protein, thereby modulating the protein's thermal stability or kinetics. General interactions refer to indirect effects whereby lipids affect membrane proteins by modulating the membrane's physical properties, e.g., its fluidity, thickness, or dipole potential. It is not widely recognized that there is a third distinct type of lipid-protein interaction. Intrinsically disordered N- or C-termini of membrane proteins can interact directly but nonspecifically with the surrounding membrane. Many peripheral membrane proteins are held to the cytoplasmic surface of the plasma membrane via a cooperative combination of two forces: hydrophobic anchoring and electrostatic attraction. An acyl chain, e.g., myristoyl, added post-translationally to one of the protein's termini inserts itself into the lipid matrix and helps hold peripheral membrane proteins onto the membrane. Electrostatic attraction occurs between positively charged basic amino acid residues (lysine and arginine) on one of the protein's terminal tails and negatively charged phospholipid head groups, such as phosphatidylserine. Phosphorylation of either serine or tyrosine residues on the terminal tails via regulatory protein kinases allows for an electrostatic switch mechanism to control trafficking of the protein. Kinase action reduces the positive charge on the protein's tail, weakening the electrostatic attraction and releasing the protein from the membrane. A similar mechanism regulates many integral membrane proteins, but here only electrostatic interactions are involved, and the electrostatic switch modulates protein activity by altering the stabilities of different protein conformational states.
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Affiliation(s)
- Ronald J. Clarke
- School of Chemistry, University of Sydney, Sydney, NSW 2006 Australia
- The University of Sydney Nano Institute, Sydney, NSW 2006 Australia
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Lev B, Chennath M, Cranfield CG, Cornelius F, Allen TW, Clarke RJ. Involvement of the alpha-subunit N-terminus in the mechanism of the Na +,K +-ATPase. Biochim Biophys Acta Mol Cell Res 2023; 1870:119539. [PMID: 37479188 DOI: 10.1016/j.bbamcr.2023.119539] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 06/26/2023] [Accepted: 07/10/2023] [Indexed: 07/23/2023]
Abstract
Previous studies have shown that cytoplasmic K+ release and the associated E2 → E1 conformational change of the Na+,K+-ATPase is a major rate-determining step of the enzyme's ion pumping cycle and hence a prime site of acute regulatory intervention. From the ionic strength dependence of the enzyme's distribution between the E2 and E1 states, it has also been found that E2 is stabilized by an electrostatic attraction. Any disruption of this electrostatic attraction would, thus, have profound effects on the rate of ion pumping. The aim of this paper is to identify the location of this interaction. Using enhanced-sampling molecular dynamics simulations with a predicted N-terminal structure added to the X-ray crystal structure of the Na+,K+-ATPase, a previously postulated salt bridge between Lys32 and Glu233 (rat sequence numbering) of the enzyme's α-subunit can be excluded. The residues never approach closely enough to form a salt bridge. In contrast, strong interactions with anionic lipid head groups were seen. To investigate the possibility of a protein-lipid interaction experimentally, the surface charge density of Na+,K+-ATPase-containing membrane fragments was estimated from zeta potential measurements to be 0.019 (± 0.001) C m-2. This is in good agreement with the charge density previously determined to be responsible for stabilization of the E2 state of 0.023 (± 0.009) C m-2 and the membrane charge density estimated here from published electron-microscopic images of 0.018C m-2. The results are, therefore, consistent with an interaction of the Na+,K+-ATPase α-subunit N-terminus with negatively-charged lipid head groups of the neighbouring cytoplasmic membrane surface as the origin of the electrostatic interaction stabilising the E2 state.
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Affiliation(s)
- B Lev
- School of Science, RMIT University, Melbourne, Vic, 3001, Australia
| | - M Chennath
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - C G Cranfield
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - F Cornelius
- Department of Biomedicine, University of Aarhus, DK-8000 Aarhus, C, Denmark
| | - T W Allen
- School of Science, RMIT University, Melbourne, Vic, 3001, Australia
| | - R J Clarke
- School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia; The University of Sydney Nano Institute, Sydney, NSW 2006, Australia.
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Al Abyad D, Serfaty X, Lefrançois P, Arbault S, Baciou L, Dupré-Crochet S, Kouzayha A, Bizouarn T. Role of the phospholipid binding sites, PX of p47 phox and PB region of Rac1, in the formation of the phagocyte NADPH oxidase complex NOX2. Biochim Biophys Acta Biomembr 2023; 1865:184180. [PMID: 37245861 DOI: 10.1016/j.bbamem.2023.184180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 05/22/2023] [Accepted: 05/23/2023] [Indexed: 05/30/2023]
Abstract
In phagocytes, superoxide anion (O2-), the precursor of reactive oxygen species, is produced by the NADPH oxidase complex to kill pathogens. Phagocyte NADPH oxidase consists of the transmembrane cytochrome b558 (cyt b558) and four cytosolic components: p40phox, p47phox, p67phox, and Rac1/2. The phagocyte activation by stimuli leads to activation of signal transduction pathways. This is followed by the translocation of cytosolic components to the membrane and their association with cyt b558 to form the active enzyme. To investigate the roles of membrane-interacting domains of the cytosolic proteins in the NADPH oxidase complex assembly and activity, we used giant unilamellar phospholipid vesicles (GUV). We also used the neutrophil-like cell line PLB-985 to investigate these roles under physiological conditions. We confirmed that the isolated proteins must be activated to bind to the membrane. We showed that their membrane binding was strengthened by the presence of the other cytosolic partners, with a key role for p47phox. We also used a fused chimera consisting of p47phox(aa 1-286), p67phox(aa 1-212) and Rac1Q61L, as well as mutated versions in the p47phox PX domain and the Rac polybasic region (PB). We showed that these two domains have a crucial role in the trimera membrane-binding and in the trimera assembly to cyt b558. They also have an impact on O2.- production in vitro and in cellulo: the PX domain strongly binding to GUV made of a mix of polar lipids; and the PB region strongly binding to the plasma membrane of neutrophils and resting PLB-985 cells.
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Affiliation(s)
- Dina Al Abyad
- Université Paris Saclay, Institut de Chimie Physique UMR 8000, CNRS, 91405 Orsay Cedex, France; Laboratory of Applied Biotechnology (LBA3B), AZM Center for Research in Biotechnology and its Applications, Doctoral School for Sciences and Technology, Lebanese University, Tripoli 1300, Lebanon
| | - Xavier Serfaty
- Université Paris Saclay, Institut de Chimie Physique UMR 8000, CNRS, 91405 Orsay Cedex, France
| | - Pauline Lefrançois
- Univ. Bordeaux, Bordeaux INP, CNRS, ISM, UMR 5255, F-33402 Talence, France
| | - Stephane Arbault
- Univ. Bordeaux, Bordeaux INP, CNRS, ISM, UMR 5255, F-33402 Talence, France; Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, F-33600 Pessac, France
| | - Laura Baciou
- Université Paris Saclay, Institut de Chimie Physique UMR 8000, CNRS, 91405 Orsay Cedex, France
| | - Sophie Dupré-Crochet
- Université Paris Saclay, Institut de Chimie Physique UMR 8000, CNRS, 91405 Orsay Cedex, France
| | - Achraf Kouzayha
- Laboratory of Applied Biotechnology (LBA3B), AZM Center for Research in Biotechnology and its Applications, Doctoral School for Sciences and Technology, Lebanese University, Tripoli 1300, Lebanon
| | - Tania Bizouarn
- Université Paris Saclay, Institut de Chimie Physique UMR 8000, CNRS, 91405 Orsay Cedex, France.
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Iriondo MN, Etxaniz A, Varela YR, Ballesteros U, Lázaro M, Valle M, Fracchiolla D, Martens S, Montes LR, Goñi FM, Alonso A. Effect of ATG12-ATG5-ATG16L1 autophagy E3-like complex on the ability of LC3/GABARAP proteins to induce vesicle tethering and fusion. Cell Mol Life Sci 2023; 80:56. [PMID: 36729310 PMCID: PMC9894987 DOI: 10.1007/s00018-023-04704-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 01/19/2023] [Accepted: 01/20/2023] [Indexed: 02/03/2023]
Abstract
In macroautophagy, the autophagosome (AP) engulfs portions of cytoplasm to allow their lysosomal degradation. AP formation in humans requires the concerted action of the ATG12 and LC3/GABARAP conjugation systems. The ATG12-ATG5-ATG16L1 or E3-like complex (E3 for short) acts as a ubiquitin-like E3 enzyme, promoting LC3/GABARAP proteins anchoring to the AP membrane. Their role in the AP expansion process is still unclear, in part because there are no studies comparing six LC3/GABARAP family member roles under the same conditions, and also because the full human E3 was only recently available. In the present study, the lipidation of six members of the LC3/GABARAP family has been reconstituted in the presence and absence of E3, and the mechanisms by which E3 and LC3/GABARAP proteins participate in vesicle tethering and fusion have been investigated. In the absence of E3, GABARAP and GABARAPL1 showed the highest activities. Differences found within LC3/GABARAP proteins suggest the existence of a lipidation threshold, lower for the GABARAP subfamily, as a requisite for tethering and inter-vesicular lipid mixing. E3 increases and speeds up lipidation and LC3/GABARAP-promoted tethering. However, E3 hampers LC3/GABARAP capacity to induce inter-vesicular lipid mixing or subsequent fusion, presumably through the formation of a rigid scaffold on the vesicle surface. Our results suggest a model of AP expansion in which the growing regions would be areas where the LC3/GABARAP proteins involved should be susceptible to lipidation in the absence of E3, or else a regulatory mechanism would allow vesicle incorporation and phagophore growth when E3 is present.
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Affiliation(s)
- Marina N. Iriondo
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940 Leioa, Spain ,Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa, Spain
| | - Asier Etxaniz
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940 Leioa, Spain ,Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa, Spain
| | - Yaiza R. Varela
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940 Leioa, Spain ,Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa, Spain
| | - Uxue Ballesteros
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940 Leioa, Spain ,Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa, Spain
| | - Melisa Lázaro
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 800, 48160 Derio, Bizkaia Spain
| | - Mikel Valle
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 800, 48160 Derio, Bizkaia Spain
| | - Dorotea Fracchiolla
- Max Perutz Labs, University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9, 1030 Vienna, Austria
| | - Sascha Martens
- Max Perutz Labs, University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9, 1030 Vienna, Austria
| | - L. Ruth Montes
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940 Leioa, Spain ,Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa, Spain
| | - Félix M. Goñi
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940 Leioa, Spain ,Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa, Spain
| | - Alicia Alonso
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940, Leioa, Spain. .,Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940, Leioa, Spain.
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8
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Ballesteros U, Etxaniz A, Iriondo MN, Varela YR, Lázaro M, Viguera AR, Montes LR, Valle M, Goñi FM, Alonso A. Autophagy protein LC3C binding to phospholipid and interaction with lipid membranes. Int J Biol Macromol 2022; 212:432-441. [PMID: 35618088 DOI: 10.1016/j.ijbiomac.2022.05.129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 05/16/2022] [Accepted: 05/17/2022] [Indexed: 01/18/2023]
Abstract
Autophagy is a process in which parts of the eukaryotic cell are selectively degraded in the lysosome. The materials to be catabolized are first surrounded by a double-membrane structure, the autophagosome. Autophagosome generation is a complex event, in which many proteins are involved. Among the latter, yeast Atg8 or its mammalian orthologues are essential in autophagosome membrane elongation, shaping and closure. A subfamily of the human Atg8 orthologues is formed by the proteins LC3A, LC3B, and LC3C. Previous studies suggest that, at variance with the other two, LC3C does not participate in cardiolipin-mediated mitophagy. The present study was devoted to exploring the binding of LC3C to lipid vesicles, bilayers and monolayers, and the ensuing protein-dependent perturbing effects, in the absence of the mitochondrial lipid cardiolipin. All Atg8 orthologues are covalently bound to a phospholipid prior to their involvement in autophagosome elongation. In our case, a mutant in the C-terminal amino acid, LC3C G126C, together with the use of a maleimide-derivatized phosphatidyl ethanolamine, ensured LC3C lipidation, up to 100% under certain conditions. Ultracentrifugation, surface pressure measurements, spectroscopic and cryo-electron microscopic techniques revealed that lipidated LC3C induced vesicle aggregation (5-fold faster in sonicated than in large unilamellar vesicles) and inter-vesicular lipid mixing (up to 82%), including inner-monolayer lipid mixing (up to 32%), consistent with in vitro partial vesicle fusion. LC3C was also able to cause the release of 80-90% vesicular aqueous contents. The data support the idea that LC3C would be able to help in autophagosome elongation/fusion in autophagy phenomena.
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Affiliation(s)
- Uxue Ballesteros
- Instituto Biofisika (CSIC, UPV/EHU) and Department of Biochemistry, University of the Basque Country, 48940 Leioa, Spain
| | - Asier Etxaniz
- Instituto Biofisika (CSIC, UPV/EHU) and Department of Biochemistry, University of the Basque Country, 48940 Leioa, Spain
| | - Marina N Iriondo
- Instituto Biofisika (CSIC, UPV/EHU) and Department of Biochemistry, University of the Basque Country, 48940 Leioa, Spain
| | - Yaiza R Varela
- Instituto Biofisika (CSIC, UPV/EHU) and Department of Biochemistry, University of the Basque Country, 48940 Leioa, Spain
| | - Melisa Lázaro
- CIC bioGUNE, Basque Research & Technology Alliance (BRTA), Bizkaia Technology Park, Building 800, 48160 Derio, Bizkaia, Spain
| | - Ana R Viguera
- Instituto Biofisika (CSIC, UPV/EHU) and Department of Biochemistry, University of the Basque Country, 48940 Leioa, Spain
| | - L Ruth Montes
- Instituto Biofisika (CSIC, UPV/EHU) and Department of Biochemistry, University of the Basque Country, 48940 Leioa, Spain
| | - Mikel Valle
- CIC bioGUNE, Basque Research & Technology Alliance (BRTA), Bizkaia Technology Park, Building 800, 48160 Derio, Bizkaia, Spain
| | - Félix M Goñi
- Instituto Biofisika (CSIC, UPV/EHU) and Department of Biochemistry, University of the Basque Country, 48940 Leioa, Spain
| | - Alicia Alonso
- Instituto Biofisika (CSIC, UPV/EHU) and Department of Biochemistry, University of the Basque Country, 48940 Leioa, Spain.
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Waeytens J, Turbant F, Arluison V, Raussens V, Wien F. Analysis of Bacterial Amyloid Interaction with Lipidic Membrane by Orientated Circular Dichroism and Infrared Spectroscopies. Methods Mol Biol 2022; 2538:217-234. [PMID: 35951303 DOI: 10.1007/978-1-0716-2529-3_15] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Fourier transform infrared spectroscopy (FTIR), circular dichroism (CD), and orientated circular dichroism (OCD) are complementary spectroscopies widely used for the analysis of protein samples such as the amyloids commonly renowned as neurodegenerative agents. Determining the secondary structure content of proteins, such as aggregated β-sheets inside the amyloids and in various environments, including membranes and lipids, has made these techniques very valuable and complemental to high-resolution techniques such as nuclear magnetic resonance (NMR), X-ray crystallography, and cryo-electron microscopy. FTIR and CD are extremely sensitive to structural changes of proteins due to environmental changes. Furthermore, FTIR provides information on lipid modifications upon protein binding, whereas synchrotron radiation CD (SRCD) and OCD are sensitive to the subtle structural changes occurring in β-sheet-rich proteins and their orientation or alignment with lipid bilayers. FTIR and CD techniques allow the identification of parallel and antiparallel β-sheet content and are therefore complementary. In this chapter, we present FTIR and CD/OCD applications to study the interactions of bacterial amyloids with membranes and lipids. Moreover, we show how to decipher the spectroscopic signals to obtain information on the molecular structure of amyloids and their interaction with lipids, addressing potential amyloid insertion into membranes and the lipid bilayer adjustments observed.
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Affiliation(s)
- Jehan Waeytens
- Centre de Biologie structurale et de Bioinformatique, Structure et Fonction des Membranes Biologiques, Université libre de Bruxelles, Bruxelles, Belgium
- Institut de Chimie Physique, CNRS UMR8000, Université Paris-Sud, Université Paris-Saclay, Orsay, France
| | - Florian Turbant
- Laboratoire Léon Brillouin LLB, CEA, CNRS UMR12, Université Paris Saclay, Gif-sur-Yvette, France
| | - Véronique Arluison
- Laboratoire Léon Brillouin LLB, CEA, CNRS UMR12, Université Paris Saclay, Gif-sur-Yvette, France
- Université de Paris Cité, Paris, France
| | - Vincent Raussens
- Centre de Biologie structurale et de Bioinformatique, Structure et Fonction des Membranes Biologiques, Université libre de Bruxelles, Bruxelles, Belgium.
| | - Frank Wien
- Synchrotron SOLEIL, L'Orme des Merisiers, Gif-sur-Yvette, France.
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10
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Basso LGM, Zeraik AE, Felizatti AP, Costa-Filho AJ. Membranotropic and biological activities of the membrane fusion peptides from SARS-CoV spike glycoprotein: The importance of the complete internal fusion peptide domain. Biochim Biophys Acta Biomembr 2021; 1863:183697. [PMID: 34274319 PMCID: PMC8280623 DOI: 10.1016/j.bbamem.2021.183697] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/05/2021] [Accepted: 07/10/2021] [Indexed: 11/28/2022]
Abstract
Fusion peptides (FP) are prominent hydrophobic segments of viral fusion proteins that play critical roles in viral entry. FPs interact with and insert into the host lipid membranes, triggering conformational changes in the viral protein that leads to the viral-cell fusion. Multiple membrane-active domains from the severe acute respiratory syndrome (SARS) coronavirus (CoV) spike protein have been reported to act as the functional fusion peptide such as the peptide sequence located between the S1/S2 and S2' cleavage sites (FP1), the S2'-adjacent fusion peptide domain (FP2), and the internal FP sequence (cIFP). Using a combined biophysical approach, we demonstrated that the α-helical coiled-coil-forming internal cIFP displayed the highest membrane fusion and permeabilizing activities along with membrane ordering effect in phosphatidylcholine (PC)/phosphatidylglycerol (PG) unilamellar vesicles compared to the other two N-proximal fusion peptide counterparts. While the FP1 sequence displayed intermediate membranotropic activities, the well-conserved FP2 peptide was substantially less effective in promoting fusion, leakage, and membrane ordering in PC/PG model membranes. Furthermore, Ca2+ did not enhance the FP2-induced lipid mixing activity in PC/phosphatidylserine/cholesterol lipid membranes, despite its strong erythrocyte membrane perturbation. Nonetheless, we found that the three putative SARS-CoV membrane-active fusion peptide sequences here studied altered the physical properties of model and erythrocyte membranes to different extents. The importance of the distinct membranotropic and biological activities of all SARS-CoV fusion peptide domains and the pronounced effect of the internal fusion peptide sequence to the whole spike-mediated membrane fusion process are discussed.
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Affiliation(s)
- Luis Guilherme Mansor Basso
- Laboratório de Ciências Físicas, Centro de Ciência e Tecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego, 2000, 28013-602 Campos dos Goytacazes, RJ, Brazil; Laboratório de Biofísica Molecular, Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes, 3900, 14040-901 Ribeirão Preto, SP, Brazil.
| | - Ana Eliza Zeraik
- Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego, 2000, 28013-602 Campos dos Goytacazes, RJ, Brazil; Grupo de Biofísica e Biologia Estrutural "Sérgio Mascarenhas", Instituto de Física de São Carlos, Universidade de São Paulo, Avenida Trabalhador São-carlense, 400, Centro, São Carlos, SP, Brazil
| | - Ana Paula Felizatti
- Laboratório de Produtos Naturais, Departamento de Química, Centro de Ciências Exatas e de Tecnologia, Universidade Federal de São Carlos, Rod. Washington Luiz, Km 235, Monjolinho, 13565905, São Carlos, SP, Brazil; Grupo de Biofísica e Biologia Estrutural "Sérgio Mascarenhas", Instituto de Física de São Carlos, Universidade de São Paulo, Avenida Trabalhador São-carlense, 400, Centro, São Carlos, SP, Brazil
| | - Antonio José Costa-Filho
- Laboratório de Biofísica Molecular, Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes, 3900, 14040-901 Ribeirão Preto, SP, Brazil.
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11
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Abstract
Actinoporins are a family of homologous pore forming proteins from sea anemones. They are one of the few families of eukaryotic toxins that have been characterized in depth. Actinoporins are activated by lipids in the context of bilayers, especially in cell and in model membranes containing the lipid sphingomyelin. These proteins must undergo conformational changes induced upon interaction with lipids in the membrane, where they form cytotoxic pores causing cell death and lethality. Herein we review a list of procedures and techniques to study this family of toxins, with the goal of elucidating the physicochemical, thermodynamic and structural basis for their activation by lipids. The emerging picture indicates that actinoporins undergo a stepwise process that includes binding to the membrane, oligomerization, and pore formation, in this order. The key transformation from the inactive oligomer to the active pore is catalyzed by sphingomyelin, explaining the key role of this lipid in the function of actinoporins.
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Affiliation(s)
- Jose M M Caaveiro
- Department of Global Healthcare, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka-shi, Fukuoka, Japan.
| | - Kouhei Tsumoto
- Department of Bioengineering, Graduate School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo, Japan; Institute of Medical Science, The University of Tokyo, Minato-ku, Tokyo, Japan; Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
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12
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Tsukahara T, Sahara Y, Ribeiro N, Tsukahara R, Gotoh M, Sakamoto S, Handa H, Murakami-Murofushi K. Adenine nucleotide translocase 2, a putative target protein for 2-carba cyclic phosphatidic acid in microglial cells. Cell Signal 2021; 82:109951. [PMID: 33592249 DOI: 10.1016/j.cellsig.2021.109951] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 01/12/2021] [Accepted: 01/30/2021] [Indexed: 11/28/2022]
Abstract
Lipid-protein interactions play essential roles in many biological phenomena. Lysophospholipid mediators, such as cyclic phosphatidic acid (cPA), have been recognized as secondary messengers, yet few cellular targets for cPA have been identified to date. Furthermore, the molecular mechanism that activates these downstream signaling events remains unknown. In this study, using metabolically stabilized cPA carba-derivative (2ccPA)-immobilized magnetic beads, we identified adenine nucleotide translocase 2 (ANT2) as a 2ccPA-interacting protein in microglial cells. 2ccPA was tested for its ability to inhibit apoptosis caused by phenylarsine oxide in microglial cells. This damage was significantly improved upon 2ccPA treatment, along with cell proliferation, apoptosis, reactive oxygen species production, and intracellular ATP levels. This is the first report to suggest the direct binding of 2ccPA to ANT2 in microglial cells and provides evidence for a new benefit of 2ccPA in protecting microglial cells from apoptotic death induced by the ANT2-mediated signaling pathway.
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Affiliation(s)
- Tamotsu Tsukahara
- Department of Pharmacology and Therapeutic Innovation, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
| | - Yasuka Sahara
- Department of Pharmacology and Therapeutic Innovation, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | | | - Ryoko Tsukahara
- Ochadai Academic Production, Ochanomizu University, Tokyo, Japan
| | - Mari Gotoh
- Institute for Human Life Innovation, Ochanomizu University, Tokyo, Japan
| | - Satoshi Sakamoto
- School of Life Science and Technology, Tokyo Institute of Technology, Kanagawa, Japan
| | - Hiroshi Handa
- Department of Chemical Biology, Tokyo Medical University, Tokyo, Japan
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13
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Dergunov AD, Litvinov DY, Malkov AA, Baserova VB, Nosova EV, Dergunova LV. Denaturation of human plasma high-density lipoproteins by urea studied by apolipoprotein A-I dissociation. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1866:158814. [PMID: 32961276 DOI: 10.1016/j.bbalip.2020.158814] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 08/30/2020] [Accepted: 09/10/2020] [Indexed: 12/12/2022]
Abstract
We studied the mechanism of HDL denaturation with concomitant apoA-I dissociation with HDL preparations from 48 patients with a wide range of plasma HDL-C and evaluated the contribution of lipid-free apoA-I into cholesterol efflux from macrophage, in particular, mediated by cholesterol transporter ABCA1. We prepared HDL by precipitation of apoB-containing lipoproteins by polyethylene glycol and used the chaotropic agent urea to denature HDL preparations. Apo-I dissociation from urea-treated HDL was assessed by the increase of preβ-band fraction with agarose gel electrophoresis followed by electro transfer and immunodetection and by the increase of ABCA1-mediated efflux of fluorescent analogue BODIPY-Cholesterol from RAW 264.7 macrophages. The HDL denaturation is governed by a single transition to fully dissociated apoA-I and the transition cooperativity decreases with increasing HDL-C. The apoA-I release depends on phospholipid concentration of HDL preparation and HDL compositional and structural heterogeneity and is well described by apolipoprotein partition between aqueous and lipid phases. Dissociated apoA-I determines the increase of ABCA1-mediated efflux of BODIPY-Cholesterol from RAW 264.7 macrophages to patient HDL. The increase in apoA-I dissociation is associated with the increase of ABCA1 gene transcript in peripheral blood mononuclear cells from patients. The low level of plasma HDL particles may be compensated by their increased potency for apoA-I release, thus suggesting apoA-I dissociation as a new HDL functional property.
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Affiliation(s)
- Alexander D Dergunov
- Laboratory of Structural Fundamentals of Lipoprotein Metabolism, National Research Centre for Preventive Medicine, Moscow, Russia.
| | - Dmitry Y Litvinov
- Laboratory of Structural Fundamentals of Lipoprotein Metabolism, National Research Centre for Preventive Medicine, Moscow, Russia
| | - Artem A Malkov
- Laboratory of Structural Fundamentals of Lipoprotein Metabolism, National Research Centre for Preventive Medicine, Moscow, Russia
| | - Veronika B Baserova
- Laboratory of Structural Fundamentals of Lipoprotein Metabolism, National Research Centre for Preventive Medicine, Moscow, Russia
| | - Elena V Nosova
- Laboratory of Functional Genomics, Institute of Molecular Genetics of the Russian Academy of Sciences, Moscow, Russia
| | - Liudmila V Dergunova
- Laboratory of Functional Genomics, Institute of Molecular Genetics of the Russian Academy of Sciences, Moscow, Russia
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14
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Huin C, Cronier S, Guégan P, Béringue V, Rezaei H, Noinville S. Conformation-dependent membrane permeabilization by neurotoxic PrP oligomers: The role of the H2H3 oligomerization domain. Arch Biochem Biophys 2020; 692:108517. [PMID: 32738196 DOI: 10.1016/j.abb.2020.108517] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 07/08/2020] [Accepted: 07/26/2020] [Indexed: 12/11/2022]
Abstract
The relationship between prion propagation and the generation of neurotoxic species and clinical onset remains unclear. Several converging lines of evidence suggest that interactions with lipids promote various precursors to form aggregation-prone states that are involved in amyloid fibrils. Here, we compared the cytotoxicities of different soluble isolated oligomeric constructs from murine full-length PrP and from the restricted helical H2H3 domain with their effects on lipid vesicles. The helical H2H3 domain is suggested to be the minimal region of PrP involved in the oligomerization process. The discrete PrP oligomers of both the full-length sequence and the H2H3 domain have de novo β-sheeted structure when interacting with the membrane. They were shown to permeabilize synthetic negatively charged vesicles in a dose-dependent manner. Restricting the polymerization domain of the full-length PrP to the H2H3 helices strongly diminished the ability of the corresponding oligomers to associate with the lipid vesicles. Furthermore, the membrane impairment mechanism occurs differently for the full-length PrP oligomers and the H2H3 helices, as shown by dye-release and black lipid membrane experiments. The membrane damage caused by the full-length PrP oligomers is correlated to their neuronal toxicity at submicromolar concentrations, as shown by cell culture assays. Although oligomers of synthetic H2H3 could compromise in vitro cell homeostasis, they followed a membrane-disruptive pattern that was different from the full-length oligomers, as revealed by the role of PrPC in cell viability assays.
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Affiliation(s)
- Cécile Huin
- Sorbonne Universités, CNRS, Institut Parisien de Chimie Moléculaire, Equipe Chimie des Polymères, 4 Place Jussieu, F-75005, Paris, France; University of Evry, F-91025, Evry, France
| | - Sabrina Cronier
- UR892, Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique (INRA), Jouy-en-Josas, France
| | - Philippe Guégan
- Sorbonne Universités, CNRS, Institut Parisien de Chimie Moléculaire, Equipe Chimie des Polymères, 4 Place Jussieu, F-75005, Paris, France
| | - Vincent Béringue
- UR892, Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique (INRA), Jouy-en-Josas, France
| | - Human Rezaei
- UR892, Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique (INRA), Jouy-en-Josas, France
| | - Sylvie Noinville
- UR892, Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique (INRA), Jouy-en-Josas, France; Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR8233, MONARIS, Université Pierre et Marie Curie, Paris, France.
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15
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Gupta A, Mahalakshmi R. Reversible folding energetics of Yersinia Ail barrel reveals a hyperfluorescent intermediate. Biochim Biophys Acta Biomembr 2019; 1862:183097. [PMID: 31672545 DOI: 10.1016/j.bbamem.2019.183097] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Revised: 10/01/2019] [Accepted: 10/10/2019] [Indexed: 12/17/2022]
Abstract
Deducing the molecular details of membrane protein folding has lately become an important area of research in biology. Using Ail, an outer membrane protein (OMP) from Yersina pestis as our model, we explore details of β-barrel folding, stability, and unfolding. Ail displays a simple transmembrane β-barrel topology. Here, we find that Ail follows a simple two-state mechanism in its folding and unfolding thermodynamics. Interestingly, Ail displays multi-step folding kinetics. The early kinetic intermediates in the folding pathway populate near the unfolded state (βT ≈ 0.20), and do not display detectable changes in the local environment of the two interface indoles. Interestingly, tryptophans regulate the late events of barrel rearrangement, and Ail thermodynamic stability. We show that W149 → Y/F/A substitution destabilizes Ail by ~0.13-1.7 kcal mol-1, but retains path-independent thermodynamic equilibrium of Ail. In surprising contrast, substituting W42 and retaining W149 shifts the thermodynamic equilibrium to an apparent kinetic retardation of only the unfolding process, which gives rise to an associated increase in scaffold stability by ~0.3-1.1 kcal mol-1. This is accompanied by the formation of an unusual hyperfluorescent state in the unfolding pathway that is more structured, and represents a conformationally dynamic unfolding intermediate with the interface W149 now lipid solvated. The defined role of each tryptophan and poorer folding efficiency of Trp mutants together presents compelling evidence for the importance of interface aromatics in the unique (un)folding pathway of Ail, and offers interesting insight on alternative pathways in generalized OMP assembly and unfolding mechanisms.
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Affiliation(s)
- Ankit Gupta
- Molecular Biophysics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal 462066. India
| | - Radhakrishnan Mahalakshmi
- Molecular Biophysics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal 462066. India.
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16
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Yang H, Yamanaka M, Nagao S, Yasuhara K, Shibata N, Higuchi Y, Hirota S. Protein surface charge effect on 3D domain swapping in cells for c-type cytochromes. Biochim Biophys Acta Proteins Proteom 2019; 1867:140265. [PMID: 31437585 DOI: 10.1016/j.bbapap.2019.140265] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 07/19/2019] [Accepted: 08/14/2019] [Indexed: 12/13/2022]
Abstract
Many c-type cytochromes (cyts) can form domain-swapped oligomers. The positively charged Hydrogenobacter thermophilus (HT) cytochrome (cyt) c552 forms domain-swapped oligomers during expression in the Escherichia coli (E. coli) expression system, but the factors influencing the oligomerization remain unrevealed. Here, we found that the dimer of the negatively charged Shewanella violacea (SV) cyt c5 exhibits a domain-swapped structure, in which the N-terminal helix is exchanged between protomers, similar to the structures of the HT cyt c552 and Pseudomonas aeruginosa (PA) cyt c551 domain-swapped dimers. Positively charged horse cyt c and HT cyt c552 domain swapped during expression in E. coli, whereas negatively charged PA cyt c551 and SV cyt c5 did not. Oligomers were formed during expression in E. coli for HT cyt c552 attached to either a co- or post-translational signal peptide for transportation through the cytoplasm membrane, but not for PA cyt c551 attached to either signal peptide. HT cyt c552 formed oligomers in E. coli in the presence and absence of rare codons. More oligomers were obtained from the in vitro folding of horse cyt c and HT cyt c552 by the addition of negatively charged liposomes during folding, whereas the amount of oligomers for the in vitro folding of PA cyt c551 and SV cyt c5 did not change significantly by the addition. These results indicate that the protein surface charge affects the oligomerization of c-type cyts in cells; positively charged c-type cyts assemble on a negatively charged membrane, inducing formation of domain-swapped oligomers during folding.
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Affiliation(s)
- Hongxu Yang
- Division of Materials Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
| | - Masaru Yamanaka
- Division of Materials Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
| | - Satoshi Nagao
- Division of Materials Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
| | - Kazuma Yasuhara
- Division of Materials Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
| | - Naoki Shibata
- Department of Life Science, Graduate School of Life Science, University of Hyogo, 3-2-1 Koto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan
| | - Yoshiki Higuchi
- Department of Life Science, Graduate School of Life Science, University of Hyogo, 3-2-1 Koto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan
| | - Shun Hirota
- Division of Materials Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
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17
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Sun C, Gennis RB. Single-particle cryo-EM studies of transmembrane proteins in SMA copolymer nanodiscs. Chem Phys Lipids 2019; 221:114-9. [PMID: 30940443 DOI: 10.1016/j.chemphyslip.2019.03.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Revised: 03/14/2019] [Accepted: 03/14/2019] [Indexed: 11/21/2022]
Abstract
Styrene-maleic acid (SMA) copolymers can extract membrane proteins from native membranes along with lipids as nanodiscs. Preparation with SMA is fast, cost-effective, and captures the native protein-lipid interactions. On the other hand, cryo-EM has become increasingly successful and efficient for structural determinations of membrane proteins, with biochemical sample preparation often the bottleneck. Three recent cryo-EM studies on the efflux transporter AcrB and the alternative complex III: cyt c oxidase supercomplex have demonstrated the potential of SMA nanodisc samples to yield high-resolution structure information of membrane proteins.
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18
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Divakara MB, Martinez D, Ravi A, Bhavana V, Ramana V, Habenstein B, Loquet A, Santosh MS. Molecular mechanisms for the destabilization of model membranes by islet amyloid polypeptide. Biophys Chem 2018; 245:34-40. [PMID: 30576976 DOI: 10.1016/j.bpc.2018.12.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 11/29/2018] [Accepted: 12/10/2018] [Indexed: 12/30/2022]
Abstract
Misfolding of human islet amyloid polypeptide (hIAPP) into insoluble aggregates is associated with Type 2 diabetes. It has been suggested that hIAPP toxicity may be due to its accumulation in pancreatic islets, causing membrane disruption and cell permeabilization, however the molecular basis underlying its lipid association are still unclear. Here, we combine solid-state NMR, fluorescence and bright field microscopy to investigate hIAPP - lipid membrane interactions. Real-time microscopy highlights a time-dependent penetration of hIAPP oligomers toward the most buried layers of the lipid vesicles until the membrane disrupts. Deuterium NMR was conducted on liposomes at different hIAPP concentration to probe lipid internal order and thermotropism. The gel-to-fluid phase transition of the lipids is decreased by the presence of hIAPP, and site-specific analysis of the order parameter showed a significant increase of lipid order for the first eight positions of the acyl chain, suggesting a partial insertion of the peptide inside the bilayer. These results offer experimental insight into the membrane destabilization of hIAPP on model membrane vesicles.
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Affiliation(s)
- Madhihalli Basavaraju Divakara
- Center for Incubation, Innovation, Research and Consultancy (CIIRC), Jyothy Institute of Technology, Thataguni, Off Kanakapura Road, Bangalore 560082, Karnataka, India; Visvesvaraya Technological University, Regional Research Centre, Jnana Sangama, Belagavi 590018, Karnataka, India
| | - Denis Martinez
- Institute of Chemistry and Biology of Membranes and Nanoobjects, Institut Européen de Chimie et Biologie (CNRS UMR 5248), Université de Bordeaux, 2 Rue Robert Escarpit, 33600 Pessac, France
| | - Ashwini Ravi
- Center for Incubation, Innovation, Research and Consultancy (CIIRC), Jyothy Institute of Technology, Thataguni, Off Kanakapura Road, Bangalore 560082, Karnataka, India; Visvesvaraya Technological University, Regional Research Centre, Jnana Sangama, Belagavi 590018, Karnataka, India
| | - Veer Bhavana
- Center for Incubation, Innovation, Research and Consultancy (CIIRC), Jyothy Institute of Technology, Thataguni, Off Kanakapura Road, Bangalore 560082, Karnataka, India; Visvesvaraya Technological University, Regional Research Centre, Jnana Sangama, Belagavi 590018, Karnataka, India
| | - Venkata Ramana
- DRDO BU CLS, Bharathiar University Campus, Coimbatore 641046, Tamil Nadu, India
| | - Birgit Habenstein
- Institute of Chemistry and Biology of Membranes and Nanoobjects, Institut Européen de Chimie et Biologie (CNRS UMR 5248), Université de Bordeaux, 2 Rue Robert Escarpit, 33600 Pessac, France.
| | - Antoine Loquet
- Institute of Chemistry and Biology of Membranes and Nanoobjects, Institut Européen de Chimie et Biologie (CNRS UMR 5248), Université de Bordeaux, 2 Rue Robert Escarpit, 33600 Pessac, France.
| | - Mysore Sridhar Santosh
- Center for Incubation, Innovation, Research and Consultancy (CIIRC), Jyothy Institute of Technology, Thataguni, Off Kanakapura Road, Bangalore 560082, Karnataka, India.
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19
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Brand I, Koch KW. Impact of the protein myristoylation on the structure of a model cell membrane in a protein bound state. Bioelectrochemistry 2018; 124:13-21. [PMID: 29990597 DOI: 10.1016/j.bioelechem.2018.06.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 06/18/2018] [Indexed: 12/18/2022]
Abstract
The neuronal calcium sensor protein recoverin is expressed in retinal rod and cone cells and is involved in the calcium-dependent control of receptor (rhodopsin) phosphorylation and receptor inactivation. In its Ca2+-saturated form recoverin is attached to membranes by an exposed myristoyl group and responds to oscillating changes of intracellular Ca2+-concentration by performing a so-called Ca2+-myristoyl switch. In this work we analyze changes in a liquid lipid bilayer interacting with myristoylated and non-myristoylated recoverin by employing polarization modulation infrared reflection absorption spectroscopy (PM IRRAS) with electrochemical control. The lipid bilayer is transferred onto a polycrystalline gold electrode using Langmuir-Blodgett Langmuir-Schaefer transfer at the surface pressure π = 30 mN m-1 which ensures, necessary for the lipid-protein interaction, liquid state of the hydrocarbon chains of phospholipids. The model lipid bilayers are adsorbed directly on the Au electrode surface at transmembrane potentials -0.2 < ∆ϕM|S < 0.25 V. The interaction with recoverin leads to a stabilization of the adsorbed state of the lipid bilayer at positive transmembrane potentials. The interaction leads to a decrease in the surface charge density that accumulates on the membrane covered electrode surface, indicating changes in the lateral interactions in the lipid membrane. In situ spectroelectrochemical studies confirm orientation changes in the hydrophobic environment of the model membrane. Insertion of the myristoyl group of recoverin into the membrane is connected with an increase in the tilt of the hydrocarbon chains with respect to the surface normal and decrease in the bilayer thickness. Potential-induced pore formation and desorption of the lipid bilayer from the membrane surface is accompanied by the removal of the acyl chains of recoverin from the membrane.
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Affiliation(s)
- Izabella Brand
- University of Oldenburg, Department of Chemistry, D-26111 Oldenburg, Germany.
| | - Karl-Wilhelm Koch
- University of Oldenburg, Department of Neuroscience, D-26111 Oldenburg, Germany
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20
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Del Vecchio K, Stahelin RV. Investigation of the phosphatidylserine binding properties of the lipid biosensor, Lactadherin C2 (LactC2), in different membrane environments. J Bioenerg Biomembr 2018; 50:1-10. [PMID: 29426977 DOI: 10.1007/s10863-018-9745-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 01/31/2018] [Indexed: 01/07/2023]
Abstract
Lipid biosensors are robust tools used in both in vitro and in vivo applications of lipid imaging and lipid detection. Lactadherin C2 (LactC2) was described in 2000 as being a potent and specific sensor for phosphatidylserine (PS) (Andersen et al. Biochemistry 39:6200-6206, 2000). PS is an anionic phospholipid enriched in the inner leaflet of the plasma membrane and has paramount roles in apoptosis, cells signaling, and autophagy. The myriad roles PS plays in membrane dynamics make monitoring PS levels and function an important endeavor. LactC2 has functioned as a tantamount PS biosensor namely in the field of cellular imaging. While PS specificity and high affinity of LactC2 for PS containing membranes has been well established, much less is known regarding LactC2 selectivity for subcellular pools of PS or PS within different membrane environments (e.g., in the presence of cholesterol). Thus, there has been a lack of studies that have compared LactC2 PS sensitivity based upon the acyl chain length and saturation or the presence of other host lipids such as cholesterol. Here, we use surface plasmon resonance as a label-free method to quantitatively assess the apparent binding affinity of LactC2 for membranes containing PS with different acyl chains, different fluidity, as well as representative lipid vesicle mimetics of cellular membranes. Results demonstrate that LactC2 is an unbiased sensor for PS, and can sensitively interact with membranes containing PS with different acyl chain saturation and interact with PS species in a cholesterol-independent manner.
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Affiliation(s)
- Kathryn Del Vecchio
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Robert V Stahelin
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA. .,Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, 47907, USA.
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Abstract
Spectrin-based proteinaceous membrane skeletal network has been found to be implicated in membrane disorders like hereditary spherocytosis (HS). HS greatly affects eryptosis via loss of membrane asymmetry which is seen to be the case in haemoglobin disorders like thalassemia and sickle cell disease as well. The biological implications of the status of membrane asymmetry are strongly correlated to spectrin interactions with aminophospholipids, e.g. PE and PS. Fluorescence and X-ray reflectivity (XRR) measurements of spectrin interactions with small unilamellar vesicles (SUVs) and cushioned bilayers of phospholipids, respectively, were studied. Both the XRR and fluorescence measurements led to the characterization of spectrin orientation on the surface of lipid bilayer of phosphatidylcholine (PC) and PC/aminophospholipid mixed membrane systems showing formation of a uniform layer of spectrin on top of the mixed phospholipid bilayer. Fluorescence studies show that spectrin interacts with PC and phosphatidylethanolamine (PE)/phosphatidylserine (PS) membranes with binding dissociation constants (Kd) in the nanomolar range indicating the role of spectrin in the maintenance of the overall membrane asymmetry of erythrocytes.
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Affiliation(s)
- Sauvik Sarkar
- Crystallography & Molecular Biology Division, Saha Institute of Nuclear Physics, HBNI, Kolkata, India
| | - Dipayan Bose
- Crystallography & Molecular Biology Division, Saha Institute of Nuclear Physics, HBNI, Kolkata, India
| | - Rajendra P Giri
- Surface Physics & Material Science Division, Saha Institute of Nuclear Physics, HBNI, Kolkata, India
| | - Mrinmay K Mukhopadhyay
- Surface Physics & Material Science Division, Saha Institute of Nuclear Physics, HBNI, Kolkata, India
| | - Abhijit Chakrabarti
- Crystallography & Molecular Biology Division, Saha Institute of Nuclear Physics, HBNI, Kolkata, India.
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22
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Abstract
Mechanosensitive (MS) channels protect bacteria against hypo-osmotic shock and fulfil additional functions. Hypo-osmotic shock leads to high turgor pressure that can cause cell rupture and death. MS channels open under these conditions and release unspecifically solutes and consequently the turgor pressure. They can recognise the raised pressure via the increased tension in the cell membrane. Currently, a better understanding how MS channels can sense tension on molecular level is developing because the interaction of the lipid bilayer with the channel is being investigated in detail. The MS channel of large conductance (MscL) and of small conductance (MscS) have been distinguished and studied in molecular detail. In addition, larger channels were found that contain a homologous region corresponding to MscS so that MscS represents a family of channels. Often several members of this family are present in a species. The importance of this family is underlined by the fact that members can be found not only in bacteria but also in higher organisms. While MscL and MscS have been studied for years in particular by electrophysiology, mutagenesis, molecular dynamics, X-ray crystallography and other biophysical techniques, only recently more details are emerging about other members of the MscS-family.
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23
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Zhang Q, Yang H. Migration of PIP 2 on KCNQ2 Surface Revealed by Molecular Dynamics Simulations. Methods Mol Biol 2018; 1684:151-61. [PMID: 29058190 DOI: 10.1007/978-1-4939-7362-0_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Lipids and membrane proteins are the main components of cell membranes. Lipid-protein interactions are dynamic because these interactions typically occur on shallow protein surface clefts. Molecular dynamics (MD) simulations provide a tool for studying the dynamics of these interactions. Here, we describe the interactions of phosphatidylinositol-4,5-bisphosphate (PIP2) with both the open and closed states of a KCNQ2 channel. Through these methods, we show that a lipid can migrate between different binding sites in a protein and this migration modulates protein functions.
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24
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Mirheydari M, Mann EK, Kooijman EE. Interaction of a model apolipoprotein, apoLp-III, with an oil-phospholipid interface. Biochim Biophys Acta Biomembr 2017; 1860:396-406. [PMID: 29030246 DOI: 10.1016/j.bbamem.2017.10.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 09/22/2017] [Accepted: 10/08/2017] [Indexed: 01/29/2023]
Abstract
Lipid droplets are "small" organelles that play an important role in de novo synthesis of new membrane, and steroid hormones, as well as in energy storage. The way proteins interact specifically with the oil-(phospho-)lipid monolayer interface of lipid droplets is a relatively unexplored but crucial question. Here, we use our home built liquid droplet tensiometer to mimic intracellular lipid droplets and study protein-lipid interactions at this interface. As model neutral lipid binding protein, we use apoLp-III, an amphipathic α-helix bundle protein. This domain is also found in proteins from the perilipin family and in apoE. Protein binding to the monolayer is studied by the decrease in the oil/water surface tension. Previous work used POPC (one of the major lipids found on lipid droplets) to form the phospholipid monolayer on the triolein surface. Here we expand this work by incorporating other lipids with different physico-chemical properties to study the effect of charge and lipid head-group size. This study sheds light on the affinity of this important protein domain to interact with lipids.
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Affiliation(s)
- Mona Mirheydari
- Physics Department, Kent State University, Kent, OH 44242, United States.
| | - Elizabeth K Mann
- Physics Department, Kent State University, Kent, OH 44242, United States
| | - Edgar E Kooijman
- Department of Biological Sciences, Kent State University, Kent, OH 44242, United States
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25
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Korytowski A, Abuillan W, Amadei F, Makky A, Gumiero A, Sinning I, Gauss A, Stremmel W, Tanaka M. Accumulation of phosphatidylcholine on gut mucosal surface is not dominated by electrostatic interactions. Biochim Biophys Acta Biomembr 2017; 1859:959-965. [PMID: 28212861 DOI: 10.1016/j.bbamem.2017.02.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 01/19/2017] [Accepted: 02/11/2017] [Indexed: 02/07/2023]
Abstract
The accumulation of phosphatidylcholine (PC) in the intestinal mucus layer is crucial for the protection of colon epithelia from the bacterial attack. It has been reported that the depletion of PC is a distinct feature of ulcerative colitis. Here we addressed the question how PC interacts with its binding proteins, the mucins, which may establish the hydrophobic barrier against colonic microbiota. In the first step, the interactions of dioleoylphosphatidylcholine (DOPC) with two mucin preparations from porcine stomach, have been studied using dynamic light scattering, zeta potential measurement, and Langmuir isotherms, suggesting that mucin binds to the surface of DOPC vesicles. The enthalpy of mucin-PC interaction could be determined by isothermal titration calorimetry. The high affinity to PC found for both mucin types seems reasonable, as they mainly consist of mucin 2, a major constituent of the flowing mucus. Moreover, by the systematic variation of net charges, we concluded that the zwitterionic DOPC has the strongest binding affinity that cannot be explained within the electrostatic interactions between charged molecules.
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Affiliation(s)
- Agatha Korytowski
- Physical Chemistry of Biosystems, Institute of Physical Chemistry, Heidelberg University, D69120 Heidelberg, Germany
| | - Wasim Abuillan
- Physical Chemistry of Biosystems, Institute of Physical Chemistry, Heidelberg University, D69120 Heidelberg, Germany
| | - Federico Amadei
- Physical Chemistry of Biosystems, Institute of Physical Chemistry, Heidelberg University, D69120 Heidelberg, Germany
| | - Ali Makky
- Physical Chemistry of Biosystems, Institute of Physical Chemistry, Heidelberg University, D69120 Heidelberg, Germany
| | - Andrea Gumiero
- Heidelberg University Biochemistry Center (BZH), D69120 Heidelberg, Germany
| | - Irmgard Sinning
- Heidelberg University Biochemistry Center (BZH), D69120 Heidelberg, Germany
| | - Annika Gauss
- Department of Internal Medicine IV, University Clinics of Heidelberg, D69120 Heidelberg, Germany
| | - Wolfgang Stremmel
- Department of Internal Medicine IV, University Clinics of Heidelberg, D69120 Heidelberg, Germany.
| | - Motomu Tanaka
- Physical Chemistry of Biosystems, Institute of Physical Chemistry, Heidelberg University, D69120 Heidelberg, Germany; Institute for Integrated Cell-Material Science (WPI iCeMS), Kyoto University, 606-8501 Kyoto, Japan.
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26
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Bisen S, Seleverstov O, Belani J, Rychnovsky S, Dopico AM, Bukiya AN. Distinct mechanisms underlying cholesterol protection against alcohol-induced BK channel inhibition and resulting vasoconstriction. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:1756-1766. [PMID: 27565113 DOI: 10.1016/j.bbalip.2016.08.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 07/21/2016] [Accepted: 08/22/2016] [Indexed: 02/01/2023]
Abstract
Alcohol (ethanol) at concentrations reached in blood following moderate to heavy drinking (30-80mM) reduces cerebral artery diameter via inhibition of voltage- and calcium-gated potassium channels of large conductance (BK) in cerebral artery smooth muscle. These channels consist of channel-forming α and regulatory β1 subunits. A high-cholesterol diet protects against ethanol-induced constriction via accumulation of cholesterol within the vasculature. The molecular mechanisms of this protection remain unknown. In the present work, we demonstrate that in vitro cholesterol enrichment of rat middle cerebral arteries significantly increased cholesterol within arterial tissues and blunted constriction by 50mM of ethanol. Ethanol-induced BK channel inhibition in inside-out patches excised from freshly isolated cerebral artery myocytes was also abolished by cholesterol enrichment. Enrichment of arteries with enantiomeric cholesterol (ent-cholesterol) also blunted BK channel inhibition and cerebral artery constriction in response to ethanol. The similar protection of cholesterol and ent-cholesterol against ethanol action indicates that this protection does not require protein site(s) that specifically sense natural cholesterol. Cholesterol-driven protection against ethanol-induced BK channel inhibition and vasoconstriction was replicated in myocytes and middle cerebral arteries of C57BL/6 mice. BK β1 subunits are known to regulate vascular diameter and its modification by ethanol. However, blunting of an ethanol effect by in vitro cholesterol enrichment was observed in arteries and myocyte membrane patches from BK β1 (KCNMB1) knockout mice. Thus, BK β1 subunits are not needed for cholesterol protection against ethanol effect on BK channel function and cerebral artery diameter.
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Affiliation(s)
- Shivantika Bisen
- Department of Pharmacology, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Olga Seleverstov
- Department of Pharmacology, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Jitendra Belani
- Department of Chemistry, School of Physical Sciences, University of California, Irvine, 3038B FRH, Mail Code: 2025, Irvine, CA 92697, USA
| | - Scott Rychnovsky
- Department of Chemistry, School of Physical Sciences, University of California, Irvine, 3038B FRH, Mail Code: 2025, Irvine, CA 92697, USA
| | - Alex M Dopico
- Department of Pharmacology, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Anna N Bukiya
- Department of Pharmacology, The University of Tennessee Health Science Center, Memphis, TN 38163, USA.
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27
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Lombana L, Ortega-Atienza S, Gómez-Gutiérrez J, Yélamos B, Peterson DL, Gavilanes F. The deletion of residues 268-292 of E1 impairs the ability of HCV envelope proteins to induce pore formation. Virus Res 2016; 217:63-70. [PMID: 26945847 DOI: 10.1016/j.virusres.2016.02.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 02/05/2016] [Accepted: 02/08/2016] [Indexed: 12/25/2022]
Abstract
We have obtained a chimeric protein containing the ectodomains of hepatitis C virus (HCV) envelope proteins but lacking the region 268-292 of E1. All its structural properties are coincident with those of the corresponding full length chimera. The deleted and entire chimeras were compared in terms of their membrane destabilizing properties. No differences were found in their ability to induce vesicle aggregation and lipid mixing but the deleted chimera showed a reduced capacity to promote leakage. The role of the deletion was also studied by obtaining HCV pseudoparticles (HCVpp). Both E1 and E2, and also the E1 deleted mutant, were incorporated into HCVpp to a similar level. However, HCVpp containing the E1 deleted protein are almost unable to infect Huh7 cells. These results point to the involvement of the region 268-292 in the formation of pores in the membrane necessary for the complete fusion of the membranes.
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Affiliation(s)
- Laura Lombana
- Department of Biochemistry and Molecular Biology, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Sara Ortega-Atienza
- Department of Biochemistry and Molecular Biology, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Julián Gómez-Gutiérrez
- Department of Biochemistry and Molecular Biology, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Belén Yélamos
- Department of Biochemistry and Molecular Biology, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Darrell L Peterson
- Department of Biochemistry and Molecular Biology, Medical College of Virginia, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Francisco Gavilanes
- Department of Biochemistry and Molecular Biology, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain.
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28
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Laage S, Tao Y, McDermott AE. Cardiolipin interaction with subunit c of ATP synthase: solid-state NMR characterization. Biochim Biophys Acta 2015; 1848:260-5. [PMID: 25168468 DOI: 10.1016/j.bbamem.2014.08.021] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Revised: 08/12/2014] [Accepted: 08/16/2014] [Indexed: 01/29/2023]
Abstract
The interaction of lipids with subunit c from F1F0 ATP synthase is studied by biophysical methods. Subunit c from both Escherichia coli and Streptococcus pneumoniae interacts and copurifies with cardiolipin. Solid state NMR data on oligomeric rings of F0 show that the cardiolipin interacts with the c subunit in membrane bilayers. These studies offer strong support for the hypothesis that F0 has specific interactions with cardiolipin.
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29
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Abstract
The fluid mosaic model of Singer and Nicolson in 1972 shows how proteins are embedded in membranes. To elucidate the interactions between proteins and the surrounding lipids, stearic acid (SA) and bovine serum albumin (BSA) were used as lipid-protein components to mimic the normal membrane bilayer environment using the Langmuir-Blodgett technique. Surface pressure (π)-molecular area (A) isotherms were recorded for the SA monolayer in the presence of BSA on water. The mixed monolayer was successfully transferred onto an oxidized silicon wafer and imaged by tapping mode atomic force microscopy (AFM). Miscibility, compressibility and thermodynamic stability of the mixed system were examined. A large negative deviation of A ex, together with the minimum value of ΔG ex, was observed when the mole fraction of BSA (X BSA) was 0.8, indicating this to be the most stable mixture. In a compressibility analysis, X BSA was observed at below 50 mN m(-1), denoting a liquid-expanded phase and showing the occurrence of a strong interaction of SA with BSA molecules in this phase. AFM observations supported the quantitative data indicating that BSA was strongly attracted onto the membrane surface as predicted.
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Affiliation(s)
- Lai Ti Gew
- Department of Biological Sciences, Faculty of Science and Technology, Sunway University, No. 5, Jalan Universiti, Bandar Sunway, Petaling Jaya, Selangor 46150, Malaysia
- Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Misni Misran
- Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia
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