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Kwok E, Otto SC, Khuu P, Carpenter AP, Codding SJ, Reardon PN, Vanegas J, Kumar TM, Kuykendall CJ, Mehl RA, Baio J, Johnson CP. The Dysferlin C2A Domain Binds PI(4,5)P2 and Penetrates Membranes. J Mol Biol 2023; 435:168193. [PMID: 37406927 PMCID: PMC10699586 DOI: 10.1016/j.jmb.2023.168193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 06/22/2023] [Accepted: 06/27/2023] [Indexed: 07/07/2023]
Abstract
Dysferlin is a large membrane protein found most prominently in striated muscle. Loss of dysferlin activity is associated with reduced exocytosis, abnormal intracellular Ca2+ and the muscle diseases limb-girdle muscular dystrophy and Miyoshi myopathy. The cytosolic region of dysferlin consists of seven C2 domains with mutations in the C2A domain at the N-terminus resulting in pathology. Despite the importance of Ca2+ and membrane binding activities of the C2A domain for dysferlin function, the mechanism of the domain remains poorly characterized. In this study we find that the C2A domain preferentially binds membranes containing PI(4,5)P2 through an interaction mediated by residues Y23, K32, K33, and R77 on the concave face of the domain. We also found that subsequent to membrane binding, the C2A domain inserts residues on the Ca2+ binding loops into the membrane. Analysis of solution NMR measurements indicate that the domain inhabits two distinct structural states, with Ca2+ shifting the population between states towards a more rigid structure with greater affinity for PI(4,5)P2. Based on our results, we propose a mechanism where Ca2+ converts C2A from a structurally dynamic, low PI(4,5)P2 affinity state to a high affinity state that targets dysferlin to PI(4,5)P2 enriched membranes through interaction with Tyr23, K32, K33, and R77. Binding also involves changes in lipid packing and insertion by the third Ca2+ binding loop of the C2 domain into the membrane, which would contribute to dysferlin function in exocytosis and Ca2+ regulation.
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Affiliation(s)
- Ethiene Kwok
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Shauna C Otto
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Patricia Khuu
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Andrew P Carpenter
- Department of Chemical Engineering, Oregon State University, Corvallis, OR 97331, USA
| | - Sara J Codding
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | | | - Juan Vanegas
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Tanushri M Kumar
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Chapman J Kuykendall
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Ryan A Mehl
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Joe Baio
- Department of Chemical Engineering, Oregon State University, Corvallis, OR 97331, USA
| | - Colin P Johnson
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA.
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2
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Drescher DG, Drescher MJ, Selvakumar D, Annam NP. Analysis of Dysferlin Direct Interactions with Putative Repair Proteins Links Apoptotic Signaling to Ca 2+ Elevation via PDCD6 and FKBP8. Int J Mol Sci 2023; 24:4707. [PMID: 36902136 PMCID: PMC10002499 DOI: 10.3390/ijms24054707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 02/19/2023] [Accepted: 02/24/2023] [Indexed: 03/05/2023] Open
Abstract
Quantitative surface plasmon resonance (SPR) was utilized to determine binding strength and calcium dependence of direct interactions between dysferlin and proteins likely to mediate skeletal muscle repair, interrupted in limb girdle muscular dystrophy type 2B/R2. Dysferlin canonical C2A (cC2A) and C2F/G domains directly interacted with annexin A1, calpain-3, caveolin-3, affixin, AHNAK1, syntaxin-4, and mitsugumin-53, with cC2A the primary target and C2F lesser involved, overall demonstrating positive calcium dependence. Dysferlin C2 pairings alone showed negative calcium dependence in almost all cases. Like otoferlin, dysferlin directly interacted via its carboxy terminus with FKBP8, an anti-apoptotic outer mitochondrial membrane protein, and via its C2DE domain with apoptosis-linked gene (ALG-2/PDCD6), linking anti-apoptosis with apoptosis. Confocal Z-stack immunofluorescence confirmed co-compartmentalization of PDCD6 and FKBP8 at the sarcolemmal membrane. Our evidence supports the hypothesis that prior to injury, dysferlin C2 domains self-interact and give rise to a folded, compact structure as indicated for otoferlin. With elevation of intracellular Ca2+ in injury, dysferlin would unfold and expose the cC2A domain for interaction with annexin A1, calpain-3, mitsugumin 53, affixin, and caveolin-3, and dysferlin would realign from its interactions with PDCD6 at basal calcium levels to interact strongly with FKBP8, an intramolecular rearrangement facilitating membrane repair.
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Affiliation(s)
- Dennis G. Drescher
- Laboratory of Bio-otology, Department of Otolaryngology, Wayne State University School of Medicine, Detroit, MI 48201, USA
- Department of Biochemistry, Microbiology and Immunology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Marian J. Drescher
- Laboratory of Bio-otology, Department of Otolaryngology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Dakshnamurthy Selvakumar
- Laboratory of Bio-otology, Department of Otolaryngology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Neeraja P. Annam
- Laboratory of Bio-otology, Department of Otolaryngology, Wayne State University School of Medicine, Detroit, MI 48201, USA
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3
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Carpenter AP, Khuu P, Weidner T, Johnson CP, Roeters SJ, Baio JE. Orientation of the Dysferlin C2A Domain is Responsive to the Composition of Lipid Membranes. J Phys Chem B 2023; 127:577-589. [PMID: 36608331 DOI: 10.1021/acs.jpcb.2c06716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Dysferlin is a 230 kD protein that plays a critical function in the active resealing of micron-sized injuries to the muscle sarcolemma by recruiting vesicles to patch the injured site via vesicle fusion. Muscular dystrophy is observed in humans when mutations disrupt this repair process or dysferlin is absent. While lipid binding by dysferlin's C2A domain (dysC2A) is considered fundamental to the membrane resealing process, the molecular mechanism of this interaction is not fully understood. By applying nonlinear surface-specific vibrational spectroscopy, we have successfully demonstrated that dysferlin's N-terminal C2A domain (dysC2A) alters its binding orientation in response to a membrane's lipid composition. These experiments reveal that dysC2A utilizes a generic electrostatic binding interaction to bind to most anionic lipid surfaces, inserting its calcium binding loops into the lipid surface while orienting its β-sheets 30-40° from surface normal. However, at lipid surfaces, where PI(4,5)P2 is present, dysC2A tilts its β-sheets more than 60° from surface normal to expose a polybasic face, while it binds to the PI(4,5)P2 surface. Both lipid binding mechanisms are shown to occur alongside dysC2A-induced lipid clustering. These different binding mechanisms suggest that dysC2A could provide a molecular cue to the larger dysferlin protein as to signal whether it is bound to the sarcolemma or another lipid surface.
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Affiliation(s)
- Andrew P Carpenter
- The School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, Oregon97331, United States
| | - Patricia Khuu
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, Oregon97331, United States
| | - Tobias Weidner
- Department of Chemistry, Aarhus University, 8000Aarhus C, Denmark
| | - Colin P Johnson
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, Oregon97331, United States
| | - Steven J Roeters
- Department of Chemistry, Aarhus University, 8000Aarhus C, Denmark
| | - Joe E Baio
- The School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, Oregon97331, United States
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Yasa J, Reed CE, Bournazos AM, Evesson FJ, Pang I, Graham ME, Wark JR, Nijagal B, Kwan KH, Kwiatkowski T, Jung R, Weisleder N, Cooper ST, Lemckert FA. Minimal expression of dysferlin prevents development of dysferlinopathy in dysferlin exon 40a knockout mice. Acta Neuropathol Commun 2023; 11:15. [PMID: 36653852 PMCID: PMC9847081 DOI: 10.1186/s40478-022-01473-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 11/03/2022] [Indexed: 01/19/2023] Open
Abstract
Dysferlin is a Ca2+-activated lipid binding protein implicated in muscle membrane repair. Recessive variants in DYSF result in dysferlinopathy, a progressive muscular dystrophy. We showed previously that calpain cleavage within a motif encoded by alternatively spliced exon 40a releases a 72 kDa C-terminal minidysferlin recruited to injured sarcolemma. Herein we use CRISPR/Cas9 gene editing to knock out murine Dysf exon 40a, to specifically assess its role in membrane repair and development of dysferlinopathy. We created three Dysf exon 40a knockout (40aKO) mouse lines that each express different levels of dysferlin protein ranging from ~ 90%, ~ 50% and ~ 10-20% levels of wild-type. Histopathological analysis of skeletal muscles from all 12-month-old 40aKO lines showed virtual absence of dystrophic features and normal membrane repair capacity for all three 40aKO lines, as compared with dysferlin-null BLAJ mice. Further, lipidomic and proteomic analyses on 18wk old quadriceps show all three 40aKO lines are spared the profound lipidomic/proteomic imbalance that characterises dysferlin-deficient BLAJ muscles. Collective results indicate that membrane repair does not depend upon calpain cleavage within exon 40a and that ~ 10-20% of WT dysferlin protein expression is sufficient to maintain the muscle lipidome, proteome and membrane repair capacity to crucially prevent development of dysferlinopathy.
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Affiliation(s)
- Joe Yasa
- grid.413973.b0000 0000 9690 854XKids Neuroscience Centre, The Children’s Hospital at Westmead, Cnr Hawkesbury Road, Hainsworth Street, Westmead, Sydney, NSW 2145 Australia ,grid.414235.50000 0004 0619 2154Functional Neuromics, Children’s Medical Research Institute, Westmead, Sydney, NSW Australia
| | - Claudia E. Reed
- grid.413973.b0000 0000 9690 854XKids Neuroscience Centre, The Children’s Hospital at Westmead, Cnr Hawkesbury Road, Hainsworth Street, Westmead, Sydney, NSW 2145 Australia ,grid.1013.30000 0004 1936 834XDiscipline of Child and Adolescent Health, Faculty of Medicine, University of Sydney, Sydney, NSW Australia
| | - Adam M. Bournazos
- grid.413973.b0000 0000 9690 854XKids Neuroscience Centre, The Children’s Hospital at Westmead, Cnr Hawkesbury Road, Hainsworth Street, Westmead, Sydney, NSW 2145 Australia ,grid.1013.30000 0004 1936 834XDiscipline of Child and Adolescent Health, Faculty of Medicine, University of Sydney, Sydney, NSW Australia
| | - Frances J. Evesson
- grid.413973.b0000 0000 9690 854XKids Neuroscience Centre, The Children’s Hospital at Westmead, Cnr Hawkesbury Road, Hainsworth Street, Westmead, Sydney, NSW 2145 Australia ,grid.414235.50000 0004 0619 2154Functional Neuromics, Children’s Medical Research Institute, Westmead, Sydney, NSW Australia ,grid.1013.30000 0004 1936 834XDiscipline of Child and Adolescent Health, Faculty of Medicine, University of Sydney, Sydney, NSW Australia
| | - Ignatius Pang
- grid.414235.50000 0004 0619 2154Synapse Proteomics, Children’s Medical Research Institute, The University of Sydney, Westmead, NSW Australia
| | - Mark E. Graham
- grid.414235.50000 0004 0619 2154Synapse Proteomics, Children’s Medical Research Institute, The University of Sydney, Westmead, NSW Australia
| | - Jesse R. Wark
- grid.1013.30000 0004 1936 834XOperations, Children’s Medical Research Institute, The University of Sydney, Westmead, NSW Australia
| | - Brunda Nijagal
- grid.1008.90000 0001 2179 088XMetabolomics Australia, Bio21 Institute, The University of Melbourne, Victoria, Australia
| | - Kim H. Kwan
- grid.1008.90000 0001 2179 088XMetabolomics Australia, Bio21 Institute, The University of Melbourne, Victoria, Australia
| | - Thomas Kwiatkowski
- grid.268132.c0000 0001 0701 2416West Chester University, West Chester, PA 19383 USA
| | - Rachel Jung
- grid.412332.50000 0001 1545 0811Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH 43210-1252 USA
| | - Noah Weisleder
- grid.412332.50000 0001 1545 0811Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH 43210-1252 USA
| | - Sandra T. Cooper
- grid.413973.b0000 0000 9690 854XKids Neuroscience Centre, The Children’s Hospital at Westmead, Cnr Hawkesbury Road, Hainsworth Street, Westmead, Sydney, NSW 2145 Australia ,grid.414235.50000 0004 0619 2154Functional Neuromics, Children’s Medical Research Institute, Westmead, Sydney, NSW Australia ,grid.1013.30000 0004 1936 834XDiscipline of Child and Adolescent Health, Faculty of Medicine, University of Sydney, Sydney, NSW Australia
| | - Frances A. Lemckert
- grid.413973.b0000 0000 9690 854XKids Neuroscience Centre, The Children’s Hospital at Westmead, Cnr Hawkesbury Road, Hainsworth Street, Westmead, Sydney, NSW 2145 Australia ,grid.414235.50000 0004 0619 2154Functional Neuromics, Children’s Medical Research Institute, Westmead, Sydney, NSW Australia ,grid.1013.30000 0004 1936 834XDiscipline of Child and Adolescent Health, Faculty of Medicine, University of Sydney, Sydney, NSW Australia
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Golbek TW, Harper BJ, Harper SL, Baio JE. Shape-dependent gold nanoparticle interactions with a model cell membrane. Biointerphases 2022; 17:061003. [PMID: 36347646 PMCID: PMC9646251 DOI: 10.1116/6.0002183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 10/11/2022] [Accepted: 10/13/2022] [Indexed: 11/11/2022] Open
Abstract
Customizable gold nanoparticle platforms are motivating innovations in drug discovery with massive therapeutic potential due to their biocompatibility, stability, and imaging capabilities. Further development requires the understanding of how discrete differences in shape, charge, or surface chemistry affect the drug delivery process of the nanoparticle. The nanoparticle shape can have a significant impact on nanoparticle function as this can, for example, drastically change the surface area available for modifications, such as surface ligand density. In order to investigate the effects of nanoparticle shape on the structure of cell membranes, we directly probed nanoparticle-lipid interactions with an interface sensitive technique termed sum frequency generation (SFG) vibrational spectroscopy. Both gold nanostars and gold nanospheres with positively charged ligands were allowed to interact with a model cell membrane and changes in the membrane structure were directly observed by specific SFG vibrational modes related to molecular bonds within the lipids. The SFG results demonstrate that the +Au nanostars both penetrated and impacted the ordering of the lipids that made up the membrane, while very little structural changes to the model membrane were observed by SFG for the +Au nanospheres interacting with the model membrane. This suggests that the +Au nanostars, compared to the +Au nanospheres, are more disruptive to a cell membrane. Our findings indicate the importance of shape in nanomaterial design and provide strong evidence that shape does play a role in defining nanomaterial-biological interactions.
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Affiliation(s)
| | - Bryan J Harper
- Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, Oregon 97330
| | - Stacey L Harper
- Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, Oregon 97330
| | - Joe E Baio
- School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, Oregon 97330
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Affiliation(s)
- Franz M Geiger
- Northwestern University, Evanston, Illinois 60208, United States
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7
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Choose your own adventure: Picosecond or broadband vibrational sum-frequency generation spectroscopy. Biointerphases 2022; 17:031201. [PMID: 35513338 DOI: 10.1116/6.0001844] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Vibrational sum-frequency generation (VSFG) spectroscopy is a method capable of measuring chemical structure and dynamics within the interfacial region between two bulk phases. At the core of every experimental system is a laser source that influences the experimental capabilities of the VSFG spectrometer. In this article, we discuss the differences between VSFG spectrometers built with picosecond and broadband laser sources as it will impact everything from material costs, experimental build time, experimental capabilities, and more. A focus is placed on the accessibility of the two different SFG systems to newcomers in the SFG field and provides a resource for laboratories considering incorporating VSFG spectroscopy into their research programs. This Tutorial provides a model decision tree to aid newcomers when determining whether the picosecond or femtosecond laser system is sufficient for their research program and navigates through it for a few specific scenarios.
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Muriel J, Lukyanenko V, Kwiatkowski T, Bhattacharya S, Garman D, Weisleder N, Bloch RJ. The C2 domains of dysferlin: roles in membrane localization, Ca 2+ signalling and sarcolemmal repair. J Physiol 2022; 600:1953-1968. [PMID: 35156706 PMCID: PMC9285653 DOI: 10.1113/jp282648] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 02/03/2022] [Indexed: 11/08/2022] Open
Abstract
Dysferlin is an integral membrane protein of the transverse tubules of skeletal muscle that is mutated or absent in limb girdle muscular dystrophy 2B and Miyoshi myopathy. Here we examine the role of dysferlin's seven C2 domains, C2A through C2G, in membrane repair and Ca2+ release, as well as in targeting dysferlin to the transverse tubules of skeletal muscle. We report that deletion of either domain C2A or C2B inhibits membrane repair completely, whereas deletion of C2C, C2D, C2E, C2F or C2G causes partial loss of membrane repair that is exacerbated in the absence of extracellular Ca2+ . Deletion of C2C, C2D, C2E, C2F or C2G also causes significant changes in Ca2+ release, measured as the amplitude of the Ca2+ transient before or after hypo-osmotic shock and the appearance of Ca2+ waves. Most deletants accumulate in endoplasmic reticulum. Only the C2A domain can be deleted without affecting dysferlin trafficking to transverse tubules, but Dysf-ΔC2A fails to support normal Ca2+ signalling after hypo-osmotic shock. Our data suggest that (i) every C2 domain contributes to repair; (ii) all C2 domains except C2B regulate Ca2+ signalling; (iii) transverse tubule localization is insufficient for normal Ca2+ signalling; and (iv) Ca2+ dependence of repair is mediated by C2C through C2G. Thus, dysferlin's C2 domains have distinct functions in Ca2+ signalling and sarcolemmal membrane repair and may play distinct roles in skeletal muscle. KEY POINTS: Dysferlin, a transmembrane protein containing seven C2 domains, C2A through C2G, concentrates in transverse tubules of skeletal muscle, where it stabilizes voltage-induced Ca2+ transients and participates in sarcolemmal membrane repair. Each of dysferlin's C2 domains except C2B regulate Ca2+ signalling. Localization of dysferlin variants to the transverse tubules is not sufficient to support normal Ca2+ signalling or membrane repair. Each of dysferlin's C2 domains contributes to sarcolemmal membrane repair. The Ca2+ dependence of membrane repair is mediated by C2C through C2G. Dysferlin's C2 domains therefore have distinct functions in Ca2+ signalling and sarcolemmal membrane repair.
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Affiliation(s)
- Joaquin Muriel
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Valeriy Lukyanenko
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Tom Kwiatkowski
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State College of Medicine, Columbus, OH, USA
| | - Sayak Bhattacharya
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State College of Medicine, Columbus, OH, USA
| | - Daniel Garman
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Noah Weisleder
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State College of Medicine, Columbus, OH, USA
| | - Robert J Bloch
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
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Sofińska K, Lupa D, Chachaj-Brekiesz A, Czaja M, Kobierski J, Seweryn S, Skirlińska-Nosek K, Szymonski M, Wilkosz N, Wnętrzak A, Lipiec E. Revealing local molecular distribution, orientation, phase separation, and formation of domains in artificial lipid layers: Towards comprehensive characterization of biological membranes. Adv Colloid Interface Sci 2022; 301:102614. [PMID: 35190313 DOI: 10.1016/j.cis.2022.102614] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 01/28/2022] [Accepted: 02/01/2022] [Indexed: 01/01/2023]
Abstract
Lipids, together with molecules such as DNA and proteins, are one of the most relevant systems responsible for the existence of life. Selected lipids are able to assembly into various organized structures, such as lipid membranes. The unique properties of lipid membranes determine their complex functions, not only to separate biological environments, but also to participate in regulatory functions, absorption of nutrients, cell-cell communication, endocytosis, cell signaling, and many others. Despite numerous scientific efforts, still little is known about the reason underlying the variability within lipid membranes, and its biochemical significance. In this review, we discuss the structural complexity of lipid membranes, as well as the importance to simplify studied systems in order to understand phenomena occurring in natural, complex membranes. Such systems require a model interface to be analyzed. Therefore, here we focused on analytical studies of artificial systems at various interfaces. The molecular structure of lipid membranes, specifically the nanometric thickens of molecular bilayer, limits in a major extent the choice of highly sensitive methods suitable to study such structures. Therefore, we focused on methods that combine high sensitivity, and/or chemical selectivity, and/or nanometric spatial resolution, such as atomic force microscopy, nanospectroscopy (tip-enhanced Raman spectroscopy, infrared nanospectroscopy), phase modulation infrared reflection-absorption spectroscopy, sum-frequency generation spectroscopy. We summarized experimental and theoretical approaches providing information about molecular structure and composition, lipid spatial distribution (phase separation), organization (domain shape, molecular orientation) of lipid membranes, and real-time visualization of the influence of various molecules (proteins, drugs) on their integrity. An integral part of this review discusses the latest achievements in the field of lipid layer-based biosensors.
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