Articles de revues : « Membrane nanodomains »

1

Okamoto, Yukihiro, Kaito Hamaguchi, Mayo Watanabe, Nozomi Watanabe, and Hiroshi Umakoshi. "Characterization of Phase Separated Planar Lipid Bilayer Membrane by Fluorescence Ratio Imaging and Scanning Probe Microscope." Membranes 12, no. 8 (2022): 770. http://dx.doi.org/10.3390/membranes12080770.

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The lipid membrane forms nanodomains (rafts) and shows heterogeneous properties. These nanodomains relate to significant roles in various cell functions, and thus the analysis of the nanodomains in phase-separated lipid membranes is important to clarify the function and role of the nanodomains. However, the lipid membrane possesses small-sized nanodomains and shows a small height difference between the nanodomains and their surroundings at certain lipid compositions. In addition, nanodomain analysis sometimes requires highly sensitive and expensive apparatus, such as a two-photon microscope. These have prevented the analysis by the conventional fluorescence microscope and by the topography of the scanning probe microscope (SPM), even though these are promising methods in macroscale and microscale analysis, respectively. Therefore, this study aimed to overcome these problems in nanodomain analysis. We successfully demonstrated that solvatochromic dye, LipiORDER, could analyze the phase state of the lipid membrane at the macroscale with low magnification lenses. Furthermore, we could prove that the phase mode of SPM was effective in the visualization of specific nanodomains by properties difference as well as topographic images of SPM. Hence, this combination method successfully gave much information on the phase state at the micro/macro scale, and thus this would be applied to the analysis of heterogeneous lipid membranes.

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Samhan-Arias, Alejandro K., Joana Poejo, Dorinda Marques-da-Silva, Oscar H. Martínez-Costa, and Carlos Gutierrez-Merino. "Are There Lipid Membrane-Domain Subtypes in Neurons with Different Roles in Calcium Signaling?" Molecules 28, no. 23 (2023): 7909. http://dx.doi.org/10.3390/molecules28237909.

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Lipid membrane nanodomains or lipid rafts are 10–200 nm diameter size cholesterol- and sphingolipid-enriched domains of the plasma membrane, gathering many proteins with different roles. Isolation and characterization of plasma membrane proteins by differential centrifugation and proteomic studies have revealed a remarkable diversity of proteins in these domains. The limited size of the lipid membrane nanodomain challenges the simple possibility that all of them can coexist within the same lipid membrane domain. As caveolin-1, flotillin isoforms and gangliosides are currently used as neuronal lipid membrane nanodomain markers, we first analyzed the structural features of these components forming nanodomains at the plasma membrane since they are relevant for building supramolecular complexes constituted by these molecular signatures. Among the proteins associated with neuronal lipid membrane nanodomains, there are a large number of proteins that play major roles in calcium signaling, such as ionotropic and metabotropic receptors for neurotransmitters, calcium channels, and calcium pumps. This review highlights a large variation between the calcium signaling proteins that have been reported to be associated with isolated caveolin-1 and flotillin-lipid membrane nanodomains. Since these calcium signaling proteins are scattered in different locations of the neuronal plasma membrane, i.e., in presynapses, postsynapses, axonal or dendritic trees, or in the neuronal soma, our analysis suggests that different lipid membrane-domain subtypes should exist in neurons. Furthermore, we conclude that classification of lipid membrane domains by their content in calcium signaling proteins sheds light on the roles of these domains for neuronal activities that are dependent upon the intracellular calcium concentration. Some examples described in this review include the synaptic and metabolic activity, secretion of neurotransmitters and neuromodulators, neuronal excitability (long-term potentiation and long-term depression), axonal and dendritic growth but also neuronal cell survival and death.

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Silvius, John R. "Membrane Nanodomains." Colloquium Series on Building Blocks of the Cell: Cell Structure and Function 1, no. 1 (2013): 1–103. http://dx.doi.org/10.4199/c00076ed1v01y201303bbc001.

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Liang, Pengbo, Thomas F. Stratil, Claudia Popp, et al. "Symbiotic root infections in Medicago truncatula require remorin-mediated receptor stabilization in membrane nanodomains." Proceedings of the National Academy of Sciences 115, no. 20 (2018): 5289–94. http://dx.doi.org/10.1073/pnas.1721868115.

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Plant cell infection is tightly controlled by cell surface receptor-like kinases (RLKs). Like other RLKs, the Medicago truncatula entry receptor LYK3 laterally segregates into membrane nanodomains in a stimulus-dependent manner. Although nanodomain localization arises as a generic feature of plant membrane proteins, the molecular mechanisms underlying such dynamic transitions and their functional relevance have remained poorly understood. Here we demonstrate that actin and the flotillin protein FLOT4 form the primary and indispensable core of a specific nanodomain. Infection-dependent induction of the remorin protein and secondary molecular scaffold SYMREM1 results in subsequent recruitment of ligand-activated LYK3 and its stabilization within these membrane subcompartments. Reciprocally, the majority of this LYK3 receptor pool is destabilized at the plasma membrane and undergoes rapid endocytosis in symrem1 mutants on rhizobial inoculation, resulting in premature abortion of host cell infections. These data reveal that receptor recruitment into nanodomains is indispensable for their function during host cell infection.

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Fukata, Yuko, Ariane Dimitrov, Gaelle Boncompain, Ole Vielemeyer, Franck Perez, and Masaki Fukata. "Local palmitoylation cycles define activity-regulated postsynaptic subdomains." Journal of Cell Biology 202, no. 1 (2013): 145–61. http://dx.doi.org/10.1083/jcb.201302071.

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Distinct PSD-95 clusters are primary landmarks of postsynaptic densities (PSDs), which are specialized membrane regions for synapses. However, the mechanism that defines the locations of PSD-95 clusters and whether or how they are reorganized inside individual dendritic spines remains controversial. Because palmitoylation regulates PSD-95 membrane targeting, we combined a conformation-specific recombinant antibody against palmitoylated PSD-95 with live-cell super-resolution imaging and discovered subsynaptic nanodomains composed of palmitoylated PSD-95 that serve as elementary units of the PSD. PSD-95 in nanodomains underwent continuous de/repalmitoylation cycles driven by local palmitoylating activity, ensuring the maintenance of compartmentalized PSD-95 clusters within individual spines. Plasma membrane targeting of DHHC2 palmitoyltransferase rapidly recruited PSD-95 to the plasma membrane and proved essential for postsynaptic nanodomain formation. Furthermore, changes in synaptic activity rapidly reorganized PSD-95 nano-architecture through plasma membrane–inserted DHHC2. Thus, the first genetically encoded antibody sensitive to palmitoylation reveals an instructive role of local palmitoylation machinery in creating activity-responsive PSD-95 nanodomains, contributing to the PSD (re)organization.

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Drab, Mitja, David Stopar, Veronika Kralj-Iglič, and Aleš Iglič. "Inception Mechanisms of Tunneling Nanotubes." Cells 8, no. 6 (2019): 626. http://dx.doi.org/10.3390/cells8060626.

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Tunneling nanotubes (TNTs) are thin membranous tubes that interconnect cells, representing a novel route of cell-to-cell communication and spreading of pathogens. TNTs form between many cell types, yet their inception mechanisms remain elusive. We review in this study general concepts related to the formation and stability of membranous tubular structures with a focus on a deviatoric elasticity model of membrane nanodomains. We review experimental evidence that tubular structures initiate from local membrane bending facilitated by laterally distributed proteins or anisotropic membrane nanodomains. We further discuss the numerical results of several theoretical and simulation models of nanodomain segregation suggesting the mechanisms of TNT inception and stability. We discuss the coupling of nanodomain segregation with the action of protruding cytoskeletal forces, which are mostly provided in eukaryotic cells by the polymerization of f-actin, and review recent inception mechanisms of TNTs in relation to motor proteins.

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Mesarec, Luka, Mitja Drab, Samo Penič, Veronika Kralj-Iglič, and Aleš Iglič. "On the Role of Curved Membrane Nanodomains and Passive and Active Skeleton Forces in the Determination of Cell Shape and Membrane Budding." International Journal of Molecular Sciences 22, no. 5 (2021): 2348. http://dx.doi.org/10.3390/ijms22052348.

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Biological membranes are composed of isotropic and anisotropic curved nanodomains. Anisotropic membrane components, such as Bin/Amphiphysin/Rvs (BAR) superfamily protein domains, could trigger/facilitate the growth of membrane tubular protrusions, while isotropic curved nanodomains may induce undulated (necklace-like) membrane protrusions. We review the role of isotropic and anisotropic membrane nanodomains in stability of tubular and undulated membrane structures generated or stabilized by cyto- or membrane-skeleton. We also describe the theory of spontaneous self-assembly of isotropic curved membrane nanodomains and derive the critical concentration above which the spontaneous necklace-like membrane protrusion growth is favorable. We show that the actin cytoskeleton growth inside the vesicle or cell can change its equilibrium shape, induce higher degree of segregation of membrane nanodomains or even alter the average orientation angle of anisotropic nanodomains such as BAR domains. These effects may indicate whether the actin cytoskeleton role is only to stabilize membrane protrusions or to generate them by stretching the vesicle membrane. Furthermore, we demonstrate that by taking into account the in-plane orientational ordering of anisotropic membrane nanodomains, direct interactions between them and the extrinsic (deviatoric) curvature elasticity, it is possible to explain the experimentally observed stability of oblate (discocyte) shapes of red blood cells in a broad interval of cell reduced volume. Finally, we present results of numerical calculations and Monte-Carlo simulations which indicate that the active forces of membrane skeleton and cytoskeleton applied to plasma membrane may considerably influence cell shape and membrane budding.

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Cebecauer, Marek, Mariana Amaro, Piotr Jurkiewicz, et al. "Membrane Lipid Nanodomains." Chemical Reviews 118, no. 23 (2018): 11259–97. http://dx.doi.org/10.1021/acs.chemrev.8b00322.

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Ma, Yuanqing, Elizabeth Hinde, and Katharina Gaus. "Nanodomains in biological membranes." Essays in Biochemistry 57 (February 6, 2015): 93–107. http://dx.doi.org/10.1042/bse0570093.

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Lipid rafts are defined as cholesterol- and sphingomyelin-enriched membrane domains in the plasma membrane of cells that are highly dynamic and cannot be resolved with conventional light microscopy. Membrane proteins that are embedded in the phospholipid matrix can be grouped into raft and non-raft proteins based on their association with detergent-resistant membranes in biochemical assays. Selective lipid–protein interactions not only produce heterogeneity in the membrane, but also cause the spatial compartmentalization of membrane reactions. It has been proposed that lipid rafts function as platforms during cell signalling transduction processes such as T-cell activation (see Chapter 13 (pages 165–175)). It has been proposed that raft association co-localizes specific signalling proteins that may yield the formation of the observed signalling microclusters at the immunological synapses. However, because of the nanometre size and high dynamics of lipid rafts, direct observations have been technically challenging, leading to an ongoing discussion of the lipid raft model and its alternatives. Recent developments in fluorescence imaging techniques have provided new opportunities to investigate the organization of cell membranes with unprecedented spatial resolution. In this chapter, we describe the concept of the lipid raft and alternative models and how new imaging technologies have advanced these concepts.

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Traeger, Jeremiah, Dehong Hu, Mengran Yang, Gary Stacey, and Galya Orr. "Super-Resolution Imaging of Plant Receptor-Like Kinases Uncovers Their Colocalization and Coordination with Nanometer Resolution." Membranes 13, no. 2 (2023): 142. http://dx.doi.org/10.3390/membranes13020142.

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Plant cell signaling often relies on the cellular organization of receptor-like kinases (RLKs) within membrane nanodomains to enhance signaling specificity and efficiency. Thus, nanometer-scale quantitative analysis of spatial organizations of RLKs could provide new understanding of mechanisms underlying plant responses to environmental stress. Here, we used stochastic optical reconstruction fluorescence microscopy (STORM) to quantify the colocalization of the flagellin-sensitive-2 (FLS2) receptor and the nanodomain marker, remorin, within Arabidopsis thaliana root hair cells. We found that recovery of FLS2 and remorin in the plasma membrane, following ligand-induced internalization by bacterial-flagellin-peptide (flg22), reached ~85% of their original membrane density after ~90 min. The pairs colocalized at the membrane at greater frequencies, compared with simulated randomly distributed pairs, except for directly after recovery, suggesting initial uncoordinated recovery followed by remorin and FLS2 pairing in the membrane. The purinergic receptor, P2K1, colocalized with remorin at similar frequencies as FLS2, while FLS2 and P2K1 colocalization occurred at significantly lower frequencies, suggesting that these RLKs mostly occupy distinct nanodomains. The chitin elicitor receptor, CERK1, colocalized with FLS2 and remorin at much lower frequencies, suggesting little coordination between CERK1 and FLS2. These findings emphasize STORM’s capacity to observe distinct nanodomains and degrees of coordination between plant cell receptors, and their respective immune pathways.

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Kure, Jakob L., Thommie Karlsson, Camilla B. Andersen, et al. "Using kICS to Reveal Changed Membrane Diffusion of AQP-9 Treated with Drugs." Membranes 11, no. 8 (2021): 568. http://dx.doi.org/10.3390/membranes11080568.

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The formation of nanodomains in the plasma membrane are thought to be part of membrane proteins regulation and signaling. Plasma membrane proteins are often investigated by analyzing the lateral mobility. k-space ICS (kICS) is a powerful image correlation spectroscopy (ICS) technique and a valuable supplement to fluorescence correlation spectroscopy (FCS). Here, we study the diffusion of aquaporin-9 (AQP9) in the plasma membrane, and the effect of different membrane and cytoskeleton affecting drugs, and therefore nanodomain perturbing, using kICS. We measured the diffusion coefficient of AQP9 after addition of these drugs using live cell Total Internal Reflection Fluorescence imaging on HEK-293 cells. The actin polymerization inhibitors Cytochalasin D and Latrunculin A do not affect the diffusion coefficient of AQP9. Methyl-β-Cyclodextrin decreases GFP-AQP9 diffusion coefficient in the plasma membrane. Human epidermal growth factor led to an increase in the diffusion coefficient of AQP9. These findings led to the conclusion that kICS can be used to measure diffusion AQP9, and suggests that the AQP9 is not part of nanodomains.

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Li, Guangtao, Qing Wang, Shinako Kakuda, and Erwin London. "Nanodomains can persist at physiologic temperature in plasma membrane vesicles and be modulated by altering cell lipids." Journal of Lipid Research 61, no. 5 (2020): 758–66. http://dx.doi.org/10.1194/jlr.ra119000565.

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The formation and properties of liquid-ordered (Lo) lipid domains (rafts) in the plasma membrane are still poorly understood. This limits our ability to manipulate ordered lipid domain-dependent biological functions. Giant plasma membrane vesicles (GPMVs) undergo large-scale phase separations into coexisting Lo and liquid-disordered lipid domains. However, large-scale phase separation in GPMVs detected by light microscopy is observed only at low temperatures. Comparing Förster resonance energy transfer-detected versus light microscopy-detected domain formation, we found that nanodomains, domains of nanometer size, persist at temperatures up to 20°C higher than large-scale phases, up to physiologic temperature. The persistence of nanodomains at higher temperatures is consistent with previously reported theoretical calculations. To investigate the sensitivity of nanodomains to lipid composition, GPMVs were prepared from mammalian cells in which sterol, phospholipid, or sphingolipid composition in the plasma membrane outer leaflet had been altered by cyclodextrin-catalyzed lipid exchange. Lipid substitutions that stabilize or destabilize ordered domain formation in artificial lipid vesicles had a similar effect on the thermal stability of nanodomains and large-scale phase separation in GPMVs, with nanodomains persisting at higher temperatures than large-scale phases for a wide range of lipid compositions. This indicates that it is likely that plasma membrane nanodomains can form under physiologic conditions more readily than large-scale phase separation. We also conclude that membrane lipid substitutions carried out in intact cells are able to modulate the propensity of plasma membranes to form ordered domains. This implies lipid substitutions can be used to alter biological processes dependent upon ordered domains.

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Stelate, Ayoub, Eva Tihlaříková, Kateřina Schwarzerová, Vilém Neděla, and Jan Petrášek. "Correlative Light-Environmental Scanning Electron Microscopy of Plasma Membrane Efflux Carriers of Plant Hormone Auxin." Biomolecules 11, no. 10 (2021): 1407. http://dx.doi.org/10.3390/biom11101407.

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Fluorescence light microscopy provided convincing evidence for the domain organization of plant plasma membrane (PM) proteins. Both peripheral and integral PM proteins show an inhomogeneous distribution within the PM. However, the size of PM nanodomains and protein clusters is too small to accurately determine their dimensions and nano-organization using routine confocal fluorescence microscopy and super-resolution methods. To overcome this limitation, we have developed a novel correlative light electron microscopy method (CLEM) using total internal reflection fluorescence microscopy (TIRFM) and advanced environmental scanning electron microscopy (A-ESEM). Using this technique, we determined the number of auxin efflux carriers from the PINFORMED (PIN) family (NtPIN3b-GFP) within PM nanodomains of tobacco cell PM ghosts. Protoplasts were attached to coverslips and immunostained with anti-GFP primary antibody and secondary antibody conjugated to fluorochrome and gold nanoparticles. After imaging the nanodomains within the PM with TIRFM, the samples were imaged with A-ESEM without further processing, and quantification of the average number of molecules within the nanodomain was performed. Without requiring any post-fixation and coating procedures, this method allows to study details of the organization of auxin carriers and other plant PM proteins.

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Ashrafzadeh, Parham, and Ingela Parmryd. "Methods applicable to membrane nanodomain studies?" Essays in Biochemistry 57 (February 6, 2015): 57–68. http://dx.doi.org/10.1042/bse0570057.

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Membrane nanodomains are dynamic liquid entities surrounded by another type of dynamic liquid. Diffusion can take place inside, around and in and out of the domains, and membrane components therefore continuously shift between domains and their surroundings. In the plasma membrane, there is the further complexity of links between membrane lipids and proteins both to the extracellular matrix and to intracellular proteins such as actin filaments. In addition, new membrane components are continuously delivered and old ones removed. On top of this, cells move. Taking all of this into account imposes great methodological challenges, and in the present chapter we discuss some methods that are currently used for membrane nanodomain studies, what information they can provide and their weaknesses.

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Huang, Dingquan, Yanbiao Sun, Zhiming Ma, et al. "Salicylic acid-mediated plasmodesmal closure via Remorin-dependent lipid organization." Proceedings of the National Academy of Sciences 116, no. 42 (2019): 21274–84. http://dx.doi.org/10.1073/pnas.1911892116.

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Plasmodesmata (PD) are plant-specific membrane-lined channels that create cytoplasmic and membrane continuities between adjacent cells, thereby facilitating cell–cell communication and virus movement. Plant cells have evolved diverse mechanisms to regulate PD plasticity in response to numerous environmental stimuli. In particular, during defense against plant pathogens, the defense hormone, salicylic acid (SA), plays a crucial role in the regulation of PD permeability in a callose-dependent manner. Here, we uncover a mechanism by which plants restrict the spreading of virus and PD cargoes using SA signaling by increasing lipid order and closure of PD. We showed that exogenous SA application triggered the compartmentalization of lipid raft nanodomains through a modulation of the lipid raft-regulatory protein, Remorin (REM). Genetic studies, superresolution imaging, and transmission electron microscopy observation together demonstrated that Arabidopsis REM1.2 and REM1.3 are crucial for plasma membrane nanodomain assembly to control PD aperture and functionality. In addition, we also found that a 14-3-3 epsilon protein modulates REM clustering and membrane nanodomain compartmentalization through its direct interaction with REM proteins. This study unveils a molecular mechanism by which the key plant defense hormone, SA, triggers membrane lipid nanodomain reorganization, thereby regulating PD closure to impede virus spreading.

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Vallés, Ana Sofía, and Francisco J. Barrantes. "Nanoscale Sub-Compartmentalization of the Dendritic Spine Compartment." Biomolecules 11, no. 11 (2021): 1697. http://dx.doi.org/10.3390/biom11111697.

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Compartmentalization of the membrane is essential for cells to perform highly specific tasks and spatially constrained biochemical functions in topographically defined areas. These membrane lateral heterogeneities range from nanoscopic dimensions, often involving only a few molecular constituents, to micron-sized mesoscopic domains resulting from the coalescence of nanodomains. Short-lived domains lasting for a few milliseconds coexist with more stable platforms lasting from minutes to days. This panoply of lateral domains subserves the great variety of demands of cell physiology, particularly high for those implicated in signaling. The dendritic spine, a subcellular structure of neurons at the receiving (postsynaptic) end of central nervous system excitatory synapses, exploits this compartmentalization principle. In its most frequent adult morphology, the mushroom-shaped spine harbors neurotransmitter receptors, enzymes, and scaffolding proteins tightly packed in a volume of a few femtoliters. In addition to constituting a mesoscopic lateral heterogeneity of the dendritic arborization, the dendritic spine postsynaptic membrane is further compartmentalized into spatially delimited nanodomains that execute separate functions in the synapse. This review discusses the functional relevance of compartmentalization and nanodomain organization in synaptic transmission and plasticity and exemplifies the importance of this parcelization in various neurotransmitter signaling systems operating at dendritic spines, using two fast ligand-gated ionotropic receptors, the nicotinic acetylcholine receptor and the glutamatergic receptor, and a second-messenger G-protein coupled receptor, the cannabinoid receptor, as paradigmatic examples.

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Sarmento, Maria J., Joana C. Ricardo, Mariana Amaro, and Radek Šachl. "Organization of gangliosides into membrane nanodomains." FEBS Letters 594, no. 22 (2020): 3668–97. http://dx.doi.org/10.1002/1873-3468.13871.

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Nguyen, Ngoc, Amber Lewis, Thuong Pham, Donald Sikazwe, and Kwan H. Cheng. "Exploring the Role of Anionic Lipid Nanodomains in the Membrane Disruption and Protein Folding of Human Islet Amyloid Polypeptide Oligomers on Lipid Membrane Surfaces Using Multiscale Molecular Dynamics Simulations." Molecules 28, no. 10 (2023): 4191. http://dx.doi.org/10.3390/molecules28104191.

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The aggregation of human Islet Amyloid Polypeptide (hIAPP) on cell membranes is linked to amyloid diseases. However, the physio-chemical mechanisms of how these hIAPP aggregates trigger membrane damage are unclear. Using coarse-grained and all-atom molecular dynamics simulations, we investigated the role of lipid nanodomains in the presence or absence of anionic lipids, phosphatidylserine (PS), and a ganglioside (GM1), in the membrane disruption and protein folding behaviors of hIAPP aggregates on phase-separated raft membranes. Our raft membranes contain liquid-ordered (Lo), liquid-disordered (Ld), mixed Lo/Ld (Lod), PS-cluster, and GM1-cluster nanosized domains. We observed that hIAPP aggregates bound to the Lod domain in the absence of anionic lipids, but also to the GM1-cluster- and PS-cluster-containing domains, with stronger affinity in the presence of anionic lipids. We discovered that L16 and I26 are the lipid anchoring residues of hIAPP binding to the Lod and PS-cluster domains. Finally, significant lipid acyl chain order disruption in the annular lipid shells surrounding the membrane-bound hIAPP aggregates and protein folding, particularly beta-sheet formation, in larger protein aggregates were evident. We propose that the interactions of hIAPP and both non-anionic and anionic lipid nanodomains represent key molecular events of membrane damage associated with the pathogenesis of amyloid diseases.

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Fukata, Masaki, Atsushi Sekiya, Tatsuro Murakami, Norihiko Yokoi, and Yuko Fukata. "Postsynaptic nanodomains generated by local palmitoylation cycles." Biochemical Society Transactions 43, no. 2 (2015): 199–204. http://dx.doi.org/10.1042/bst20140238.

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Precise regulation of protein assembly at specialized membrane domains is essential for diverse cellular functions including synaptic transmission. However, it is incompletely understood how protein clustering at the plasma membrane is initiated, maintained and controlled. Protein palmitoylation, a common post-translational modification, regulates protein targeting to the plasma membrane. Such modified proteins are enriched in these specialized membrane domains. In this review, we focus on palmitoylation of PSD-95, which is a major postsynaptic scaffolding protein and makes discrete postsynaptic nanodomains in a palmitoylation-dependent manner and discuss a determinant role of local palmitoylation cycles in creating highly localized hotspots at the membrane where specific proteins concentrate to organize functional domains.

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Yurtsever, Ayhan, Takeshi Yoshida, Arash Badami Behjat, Yoshihiro Araki, Rikinari Hanayama, and Takeshi Fukuma. "Structural and mechanical characteristics of exosomes from osteosarcoma cells explored by 3D-atomic force microscopy." Nanoscale 13, no. 13 (2021): 6661–77. http://dx.doi.org/10.1039/d0nr09178b.

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Schneider, Falk, Dominic Waithe, Mathias P. Clausen, et al. "Diffusion of lipids and GPI-anchored proteins in actin-free plasma membrane vesicles measured by STED-FCS." Molecular Biology of the Cell 28, no. 11 (2017): 1507–18. http://dx.doi.org/10.1091/mbc.e16-07-0536.

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Diffusion and interaction dynamics of molecules at the plasma membrane play an important role in cellular signaling and are suggested to be strongly associated with the actin cytoskeleton. Here we use superresolution STED microscopy combined with fluorescence correlation spectroscopy (STED-FCS) to access and compare the diffusion characteristics of fluorescent lipid analogues and GPI-anchored proteins (GPI-APs) in the live-cell plasma membrane and in actin cytoskeleton–free, cell-derived giant plasma membrane vesicles (GPMVs). Hindered diffusion of phospholipids and sphingolipids is abolished in the GPMVs, whereas transient nanodomain incorporation of ganglioside lipid GM1 is apparent in both the live-cell membrane and GPMVs. For GPI-APs, we detect two molecular pools in living cells; one pool shows high mobility with transient incorporation into nanodomains, and the other pool forms immobile clusters, both of which disappear in GPMVs. Our data underline the crucial role of the actin cortex in maintaining hindered diffusion modes of many but not all of the membrane molecules and highlight a powerful experimental approach to decipher specific influences on molecular plasma membrane dynamics.

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Arumugam, Senthil, and Patricia Bassereau. "Membrane nanodomains: contribution of curvature and interaction with proteins and cytoskeleton." Essays in Biochemistry 57 (February 6, 2015): 109–19. http://dx.doi.org/10.1042/bse0570109.

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The understanding of lipid membranes and their organization has undergone significant development with better techniques and therefore more resolved experiments. Many new factors and organizing principles have been discovered, and interplay between these factors is expected to result in rich functional behaviours. The major factors regulating the lateral membrane heterogeneity, apart from the well-studied phase separation, are cytoskeleton pinning, clustering of lipids and curvature. These factors are effective means to create membrane domains that provide rich biological functionality. We review the recent advances and concepts of membrane heterogeneity organization by curvature, cytoskeleton and clustering proteins.

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Nika, Konstantina, and Oreste Acuto. "Membrane nanodomains in T-cell antigen receptor signalling." Essays in Biochemistry 57 (February 6, 2015): 165–75. http://dx.doi.org/10.1042/bse0570165.

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The organization of the T-cell's plasma membrane continues to nourish the curiosity of immunologists, cell biologists and biophysicists. The main reason is the biological and biomedical interest to understand the workings of the cell–cell communication network activated by T-cells during an immune response. The molecular armamentarium of the T-cell plasma membrane helps to identify with high sensitivity, specificity and rapidity antigens from invading microbial pathogens and prepare adequate countermeasures to fend them off, while protecting from attacks against our normal tissues. Many T-cell membrane proteins act as receptors to carry out and finely tune these complex tasks. However, the TCR (T-cell receptor) holds a decisive hegemony for its crucial contribution in steering T-cell function and fate. An emerging notion is that TCR proximal signalling occurs at submicrometre-scale membrane domains. In the present chapter, we discuss the current knowledge on the TCR structure and the associated signal transduction machinery and how the notion of membrane nanodomains has decisively contributed to further understand the molecular basis of T-cell activation.

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Karner, Andreas, Benedikt Nimmervoll, Birgit Plochberger, et al. "Tuning membrane protein mobility by confinement into nanodomains." Nature Nanotechnology 12, no. 3 (2016): 260–66. http://dx.doi.org/10.1038/nnano.2016.236.

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Ott, Thomas. "Membrane nanodomains and microdomains in plant–microbe interactions." Current Opinion in Plant Biology 40 (December 2017): 82–88. http://dx.doi.org/10.1016/j.pbi.2017.08.008.

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de Wit, Gabrielle, John S. H. Danial, Philipp Kukura, and Mark I. Wallace. "Dynamic label-free imaging of lipid nanodomains." Proceedings of the National Academy of Sciences 112, no. 40 (2015): 12299–303. http://dx.doi.org/10.1073/pnas.1508483112.

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Lipid rafts are submicron proteolipid domains thought to be responsible for membrane trafficking and signaling. Their small size and transient nature put an understanding of their dynamics beyond the reach of existing techniques, leading to much contention as to their exact role. Here, we exploit the differences in light scattering from lipid bilayer phases to achieve dynamic imaging of nanoscopic lipid domains without any labels. Using phase-separated droplet interface bilayers we resolve the diffusion of domains as small as 50 nm in radius and observe nanodomain formation, destruction, and dynamic coalescence with a domain lifetime of 220 ± 60 ms. Domain dynamics on this timescale suggests an important role in modulating membrane protein function.

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García-Arribas, Aritz B., Félix M. Goñi, and Alicia Alonso. "Lipid Self-Assemblies under the Atomic Force Microscope." International Journal of Molecular Sciences 22, no. 18 (2021): 10085. http://dx.doi.org/10.3390/ijms221810085.

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Lipid model membranes are important tools in the study of biophysical processes such as lipid self-assembly and lipid–lipid interactions in cell membranes. The use of model systems to adequate and modulate complexity helps in the understanding of many events that occur in cellular membranes, that exhibit a wide variety of components, including lipids of different subfamilies (e.g., phospholipids, sphingolipids, sterols…), in addition to proteins and sugars. The capacity of lipids to segregate by themselves into different phases at the nanoscale (nanodomains) is an intriguing feature that is yet to be fully characterized in vivo due to the proposed transient nature of these domains in living systems. Model lipid membranes, instead, have the advantage of (usually) greater phase stability, together with the possibility of fully controlling the system lipid composition. Atomic force microscopy (AFM) is a powerful tool to detect the presence of meso- and nanodomains in a lipid membrane. It also allows the direct quantification of nanomechanical resistance in each phase present. In this review, we explore the main kinds of lipid assemblies used as model membranes and describe AFM experiments on model membranes. In addition, we discuss how these assemblies have extended our knowledge of membrane biophysics over the last two decades, particularly in issues related to the variability of different model membranes and the impact of supports/cytoskeleton on lipid behavior, such as segregated domain size or bilayer leaflet uncoupling.

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Heberle, Frederick A., Milka Doktorova, Haden L. Scott, Allison D. Skinkle, M. Neal Waxham, and Ilya Levental. "Direct label-free imaging of nanodomains in biomimetic and biological membranes by cryogenic electron microscopy." Proceedings of the National Academy of Sciences 117, no. 33 (2020): 19943–52. http://dx.doi.org/10.1073/pnas.2002200117.

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The nanoscale organization of biological membranes into structurally and compositionally distinct lateral domains is believed to be central to membrane function. The nature of this organization has remained elusive due to a lack of methods to directly probe nanoscopic membrane features. We show here that cryogenic electron microscopy (cryo-EM) can be used to directly image coexisting nanoscopic domains in synthetic and bioderived membranes without extrinsic probes. Analyzing a series of single-component liposomes composed of synthetic lipids of varying chain lengths, we demonstrate that cryo-EM can distinguish bilayer thickness differences as small as 0.5 Å, comparable to the resolution of small-angle scattering methods. Simulated images from computational models reveal that features in cryo-EM images result from a complex interplay between the atomic distribution normal to the plane of the bilayer and imaging parameters. Simulations of phase-separated bilayers were used to predict two sources of contrast between coexisting ordered and disordered phases within a single liposome, namely differences in membrane thickness and molecular density. We observe both sources of contrast in biomimetic membranes composed of saturated lipids, unsaturated lipids, and cholesterol. When extended to isolated mammalian plasma membranes, cryo-EM reveals similar nanoscale lateral heterogeneities. The methods reported here for direct, probe-free imaging of nanodomains in unperturbed membranes open new avenues for investigation of nanoscopic membrane organization.

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Dong, Guohua, Suzhi Li, Mouteng Yao, et al. "Super-elastic ferroelectric single-crystal membrane with continuous electric dipole rotation." Science 366, no. 6464 (2019): 475–79. http://dx.doi.org/10.1126/science.aay7221.

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Ferroelectrics are usually inflexible oxides that undergo brittle deformation. We synthesized freestanding single-crystalline ferroelectric barium titanate (BaTiO3) membranes with a damage-free lifting-off process. Our BaTiO3 membranes can undergo a ~180° folding during an in situ bending test, demonstrating a super-elasticity and ultraflexibility. We found that the origin of the super-elasticity was from the dynamic evolution of ferroelectric nanodomains. High stresses modulate the energy landscape markedly and allow the dipoles to rotate continuously between the a and c nanodomains. A continuous transition zone is formed to accommodate the variant strain and avoid high mismatch stress that usually causes fracture. The phenomenon should be possible in other ferroelectrics systems through domain engineering. The ultraflexible epitaxial ferroelectric membranes could enable many applications such as flexible sensors, memories, and electronic skins.

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Holowka, David, та Barbara Baird. "Nanodomains in early and later phases of FcɛRI signalling". Essays in Biochemistry 57 (6 лютого 2015): 147–63. http://dx.doi.org/10.1042/bse0570147.

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Our long-term efforts to elucidate receptor-mediated signalling in immune cells, particularly transmembrane signalling initiated by FcɛRI, the receptor for IgE in mast cells, led us unavoidably to contemplate the role of the heterogeneous plasma membrane. Our early investigations with fluorescence microscopy revealed co-redistribution of certain lipids and signalling components with antigen-cross-linked IgE–FcɛRI and pointed to participation of ordered membrane domains in the signalling process. With a focus on this function, we have worked along with others to develop diverse and increasingly sophisticated tools to analyse the complexity of membrane structure that facilitates regulation and targeting of signalling events. The present chapter describes how initial membrane interactions of clustered IgE–FcɛRI lead to downstream cellular responses and how biochemical information integrated with nanoscale resolution spectroscopy and imaging is providing mechanistic insights at the level of molecular complexes.

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Tran, Tuan Minh, Choon-Peng Chng, Xiaoming Pu, et al. "Potentiation of plant defense by bacterial outer membrane vesicles is mediated by membrane nanodomains." Plant Cell 34, no. 1 (2021): 395–417. http://dx.doi.org/10.1093/plcell/koab276.

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Abstract Outer membrane vesicles (OMVs) are released from the outer membranes of Gram-negative bacteria during infection and modulate host immunity during host–pathogen interactions. The mechanisms by which OMVs are perceived by plants and affect host immunity are unclear. Here, we used the pathogen Xanthomonas campestris pv. campestris to demonstrate that OMV–plant interactions at the Arabidopsis thaliana plasma membrane (PM) modulate various host processes, including endocytosis, innate immune responses, and suppression of pathogenesis by phytobacteria. The lipid phase of OMVs is highly ordered and OMVs directly insert into the Arabidopsis PM, thereby enhancing the plant PM’s lipid order; this also resulted in strengthened plant defenses. Strikingly, the integration of OMVs into the plant PM is host nanodomain- and remorin-dependent. Using coarse-grained simulations of molecular dynamics, we demonstrated that OMV integration into the plant PM depends on the membrane lipid order. Our computational simulations further showed that the saturation level of the OMV lipids could fine-tune the enhancement of host lipid order. Our work unraveled the mechanisms underlying the ability of OMVs produced by a plant pathogen to insert into the host PM, alter host membrane properties, and modulate plant immune responses.

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Lee, Sungsu, Han Yen Tan, Ivayla I. Geneva, Aleksandr Kruglov, and Peter D. Calvert. "Actin filaments partition primary cilia membranes into distinct fluid corrals." Journal of Cell Biology 217, no. 8 (2018): 2831–49. http://dx.doi.org/10.1083/jcb.201711104.

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Physical properties of primary cilia membranes in living cells were examined using two independent, high-spatiotemporal-resolution approaches: fast tracking of single quantum dot–labeled G protein–coupled receptors and a novel two-photon super-resolution fluorescence recovery after photobleaching of protein ensemble. Both approaches demonstrated the cilium membrane to be partitioned into corralled domains spanning 274 ± 20 nm, within which the receptors are transiently confined for 0.71 ± 0.09 s. The mean membrane diffusion coefficient within the corrals, Dm1 = 2.9 ± 0.41 µm2/s, showed that the ciliary membranes were among the most fluid encountered. At longer times, the apparent membrane diffusion coefficient, Dm2 = 0.23 ± 0.05 µm2/s, showed that corral boundaries impeded receptor diffusion 13-fold. Mathematical simulations predict the probability of G protein–coupled receptors crossing corral boundaries to be 1 in 472. Remarkably, latrunculin A, cytochalasin D, and jasplakinolide treatments altered the corral permeability. Ciliary membranes are thus partitioned into highly fluid membrane nanodomains that are delimited by filamentous actin.

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Tapken, W., and A. S. Murphy. "Membrane nanodomains in plants: capturing form, function, and movement." Journal of Experimental Botany 66, no. 6 (2015): 1573–86. http://dx.doi.org/10.1093/jxb/erv054.

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Chen, Xi, Angela Jen, Alice Warley, M. Jayne Lawrence, Peter J. Quinn, and Roger J. Morris. "Isolation at physiological temperature of detergent-resistant membranes with properties expected of lipid rafts: the influence of buffer composition." Biochemical Journal 417, no. 2 (2008): 525–33. http://dx.doi.org/10.1042/bj20081385.

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The failure of most non-ionic detergents to release patches of DRM (detergent-resistant membrane) at 37 °C undermines the claim that DRMs consist of lipid nanodomains that exist in an Lo (liquid ordered) phase on the living cell surface. In the present study, we have shown that inclusion of cations (Mg2+, K+) to mimic the intracellular environment stabilizes membranes during solubilization sufficiently to allow the isolation of DRMs at 37 °C, using either Triton X-100 or Brij 96. These DRMs are sensitive to chelation of cholesterol, maintain outside-out orientation of membrane glycoproteins, have prolonged (18 h) stability at 37 °C, and are vesicles or sheets up to 150–200 nm diameter. DRMs containing GPI (glycosylphosphatidylinositol)-anchored proteins PrP (prion protein) and Thy-1 can be separated by immunoaffinity isolation, in keeping with their separate organization and trafficking on the neuronal surface. Thy-1, but not PrP, DRMs are associated with actin. EM (electron microscopy) immunohistochemistry shows most PrP, and some Thy-1, to be clustered on DRMs, again maintaining their organization on the neuronal surface. For DRMs labelled for either protein, the bulk of the surface of the DRM is not labelled, indicating that the GPI-anchored protein is a minor component of its lipid domain. These 37 °C DRMs thus have properties expected of raft membrane, yet pose more questions about how proteins are organized within these nanodomains.

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Schneider, Katharina, Eric Seemann, Lutz Liebmann, et al. "ProSAP1 and membrane nanodomain-associated syndapin I promote postsynapse formation and function." Journal of Cell Biology 205, no. 2 (2014): 197–215. http://dx.doi.org/10.1083/jcb.201307088.

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Insights into mechanisms coordinating membrane remodeling, local actin nucleation, and postsynaptic scaffolding during postsynapse formation are important for understanding vertebrate brain function. Gene knockout and RNAi in individual neurons reveal that the F-BAR protein syndapin I is a crucial postsynaptic coordinator in formation of excitatory synapses. Syndapin I deficiency caused significant reductions of synapse and dendritic spine densities. These syndapin I functions reflected direct, SH3 domain–mediated associations and functional interactions with ProSAP1/Shank2. They furthermore required F-BAR domain-mediated membrane binding. Ultra-high-resolution imaging of specifically membrane-associated, endogenous syndapin I at membranes of freeze-fractured neurons revealed that membrane-bound syndapin I preferentially occurred in spines and formed clusters at distinct postsynaptic membrane subareas. Postsynaptic syndapin I deficiency led to reduced frequencies of miniature excitatory postsynaptic currents, i.e., to defects in synaptic transmission phenocopying ProSAP1/Shank2 knockout, and impairments in proper synaptic ProSAP1/Shank2 distribution. Syndapin I–enriched membrane nanodomains thus seem to be important spatial cues and organizing platforms, shaping dendritic membrane areas into synaptic compartments.

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Yang, Xiaojuan, and Wim Annaert. "The Nanoscopic Organization of Synapse Structures: A Common Basis for Cell Communication." Membranes 11, no. 4 (2021): 248. http://dx.doi.org/10.3390/membranes11040248.

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Synapse structures, including neuronal and immunological synapses, can be seen as the plasma membrane contact sites between two individual cells where information is transmitted from one cell to the other. The distance between the two plasma membranes is only a few tens of nanometers, but these areas are densely populated with functionally different proteins, including adhesion proteins, receptors, and transporters. The narrow space between the two plasma membranes has been a barrier for resolving the synaptic architecture due to the diffraction limit in conventional microscopy (~250 nm). Various advanced super-resolution microscopy techniques, such as stimulated emission depletion (STED), structured illumination microscopy (SIM), and single-molecule localization microscopy (SMLM), bypass the diffraction limit and provide a sub-diffraction-limit resolving power, ranging from 10 to 100 nm. The studies using super-resolution microscopy have revealed unprecedented details of the nanoscopic organization and dynamics of synaptic molecules. In general, most synaptic proteins appear to be heterogeneously distributed and form nanodomains at the membranes. These nanodomains are dynamic functional units, playing important roles in mediating signal transmission through synapses. Herein, we discuss our current knowledge on the super-resolution nanoscopic architecture of synapses and their functional implications, with a particular focus on the neuronal synapses and immune synapses.

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Chen, Yong, Lingyun Shao, Zahida Ali, Jiye Cai та Zheng W. Chen. "NSOM/QD-based nanoscale immunofluorescence imaging of antigen-specific T-cell receptor responses during an in vivo clonal Vγ2Vδ2 T-cell expansion". Blood 111, № 8 (2008): 4220–32. http://dx.doi.org/10.1182/blood-2007-07-101691.

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Abstract Nanoscale imaging of an in vivo antigen-specific T-cell immune response has not been reported. Here, the combined near-field scanning optical microscopy– and fluorescent quantum dot–based nanotechnology was used to perform immunofluorescence imaging of antigen-specific T-cell receptor (TCR) response in an in vivo model of clonal T-cell expansion. The near-field scanning optical microscopy/quantum dot system provided a best-optical-resolution (<50 nm) nano-scale imaging of Vγ2Vδ2 TCR on the membrane of nonstimulated Vγ2Vδ2 T cells. Before Ag-induced clonal expansion, these nonstimulating Vγ2Vδ2 TCRs appeared to be distributed differently from their αβ TCR counterparts on the cell surface. Surprisingly, Vγ2Vδ2 TCR nanoclusters not only were formed but also sustained on the membrane during an in vivo clonal expansion of Vγ2Vδ2 T cells after phosphoantigen treatment or phosphoantigen plus mycobacterial infection. The TCR nanoclusters could array to form nanodomains or microdomains on the membrane of clonally expanded Vγ2Vδ2 T cells. Interestingly, expanded Vγ2Vδ2 T cells bearing TCR nanoclusters or nanodomains were able to rerecognize phosphoantigen and to exert better effector function. These studies provided nanoscale insight into the in vivo T-cell immune response.

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Glöckner, Nina, Sven zur Oven-Krockhaus, Leander Rohr, et al. "Three-Fluorophore FRET Enables the Analysis of Ternary Protein Association in Living Plant Cells." Plants 11, no. 19 (2022): 2630. http://dx.doi.org/10.3390/plants11192630.

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Protein-protein interaction studies provide valuable insights into cellular signaling. Brassinosteroid (BR) signaling is initiated by the hormone-binding receptor Brassinosteroid Insensitive 1 (BRI1) and its co-receptor BRI1 Associated Kinase 1 (BAK1). BRI1 and BAK1 were shown to interact independently with the Receptor-Like Protein 44 (RLP44), which is implicated in BRI1/BAK1-dependent cell wall integrity perception. To demonstrate the proposed complex formation of BRI1, BAK1 and RLP44, we established three-fluorophore intensity-based spectral Förster resonance energy transfer (FRET) and FRET-fluorescence lifetime imaging microscopy (FLIM) for living plant cells. Our evidence indicates that RLP44, BRI1 and BAK1 form a ternary complex in a distinct plasma membrane nanodomain. In contrast, although the immune receptor Flagellin Sensing 2 (FLS2) also forms a heteromer with BAK1, the FLS2/BAK1 complexes are localized to other nanodomains. In conclusion, both three-fluorophore FRET approaches provide a feasible basis for studying the in vivo interaction and sub-compartmentalization of proteins in great detail.

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He, Hai-Tao, and Didier Marguet. "Detecting Nanodomains in Living Cell Membrane by Fluorescence Correlation Spectroscopy." Annual Review of Physical Chemistry 62, no. 1 (2011): 417–36. http://dx.doi.org/10.1146/annurev-physchem-032210-103402.

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Golfetto, Ottavia, Sunetra Biswas, Raphael Jorand, et al. "Opioid Receptors are Organized into Nanodomains in the Plasma Membrane." Biophysical Journal 110, no. 3 (2016): 484a. http://dx.doi.org/10.1016/j.bpj.2015.11.2587.

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Koklič, Tilen, Alenka Hrovat, Ramon Guixà-González, et al. "Electron Paramagnetic Resonance Gives Evidence for the Presence of Type 1 Gonadotropin-Releasing Hormone Receptor (GnRH-R) in Subdomains of Lipid Rafts." Molecules 26, no. 4 (2021): 973. http://dx.doi.org/10.3390/molecules26040973.

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This study investigated the effect of type 1 gonadotropin releasing hormone receptor (GnRH-R) localization within lipid rafts on the properties of plasma membrane (PM) nanodomain structure. Confocal microscopy revealed colocalization of PM-localized GnRH-R with GM1-enriched raft-like PM subdomains. Electron paramagnetic resonance spectroscopy (EPR) of a membrane-partitioned spin probe was then used to study PM fluidity of immortalized pituitary gonadotrope cell line αT3-1 and HEK-293 cells stably expressing GnRH-R and compared it with their corresponding controls (αT4 and HEK-293 cells). Computer-assisted interpretation of EPR spectra revealed three modes of spin probe movement reflecting the properties of three types of PM nanodomains. Domains with an intermediate order parameter (domain 2) were the most affected by the presence of the GnRH-Rs, which increased PM ordering (order parameter (S)) and rotational mobility of PM lipids (decreased rotational correlation time (τc)). Depletion of cholesterol by methyl-β-cyclodextrin (methyl-β-CD) inhibited agonist-induced GnRH-R internalization and intracellular Ca2+ activity and resulted in an overall reduction in PM order; an observation further supported by molecular dynamics (MD) simulations of model membrane systems. This study provides evidence that GnRH-R PM localization may be related to a subdomain of lipid rafts that has lower PM ordering, suggesting lateral heterogeneity within lipid raft domains.

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McKenna, J. F., D. J. Rolfe, S. E. D. Webb, et al. "The cell wall regulates dynamics and size of plasma-membrane nanodomains inArabidopsis." Proceedings of the National Academy of Sciences 116, no. 26 (2019): 12857–62. http://dx.doi.org/10.1073/pnas.1819077116.

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Plant plasma-membrane (PM) proteins are involved in several vital processes, such as detection of pathogens, solute transport, and cellular signaling. For these proteins to function effectively there needs to be structure within the PM allowing, for example, proteins in the same signaling cascade to be spatially organized. Here we demonstrate that several proteins with divergent functions are located in clusters of differing size in the membrane using subdiffraction-limited Airyscan confocal microscopy. Single particle tracking reveals that these proteins move at different rates within the membrane. Actin and microtubule cytoskeletons appear to significantly regulate the mobility of one of these proteins (the pathogen receptor FLS2) and we further demonstrate that the cell wall is critical for the regulation of cluster size by quantifying single particle dynamics of proteins with key roles in morphogenesis (PIN3) and pathogen perception (FLS2). We propose a model in which the cell wall and cytoskeleton are pivotal for regulation of protein cluster size and dynamics, thereby contributing to the formation and functionality of membrane nanodomains.

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Santos, Natalia, Luthary Segura, Amber Lewis, Thuong Pham, and Kwan H. Cheng. "Multiscale Modeling of Macromolecular Interactions between Tau-Amylin Oligomers and Asymmetric Lipid Nanodomains That Link Alzheimer’s and Diabetic Diseases." Molecules 29, no. 3 (2024): 740. http://dx.doi.org/10.3390/molecules29030740.

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The molecular events of protein misfolding and self-aggregation of tau and amylin are associated with the progression of Alzheimer’s and diabetes, respectively. Recent studies suggest that tau and amylin can form hetero-tau-amylin oligomers. Those hetero-oligomers are more neurotoxic than homo-tau oligomers. So far, the detailed interactions between the hetero-oligomers and the neuronal membrane are unknown. Using multiscale MD simulations, the lipid binding and protein folding behaviors of hetero-oligomers on asymmetric lipid nanodomains or raft membranes were examined. Our raft membranes contain phase-separated phosphatidylcholine (PC), cholesterol, and anionic phosphatidylserine (PS) or ganglioside (GM1) in one leaflet of the lipid bilayer. The hetero-oligomers bound more strongly to the PS and GM1 than other lipids via the hydrophobic and hydrophilic interactions, respectively, in the raft membranes. The hetero-tetramer disrupted the acyl chain orders of both PC and PS in the PS-containing raft membrane, but only the GM1 in the GM1-containing raft membrane as effectively as the homo-tau-tetramer. We discovered that the alpha-helical content in the heterodimer was greater than the sum of alpha-helical contents from isolated tau and amylin monomers on both raft membranes, indicative of a synergetic effect of tau-amylin interactions in surface-induced protein folding. Our results provide new molecular insights into understanding the cross-talk between Alzheimer’s and diabetes.

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Srinivasan, P. "Multifunctional-layered materials for creating membrane-restricted nanodomains and nanoscale imaging." Applied Physics Letters 108, no. 3 (2016): 033702. http://dx.doi.org/10.1063/1.4940388.

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Sugiyama, Michael G., Gregory D. Fairn, and Costin N. Antonescu. "EGFR signaling in breast cancer requires licensing from separate membrane nanodomains." FASEB Journal 34, S1 (2020): 1. http://dx.doi.org/10.1096/fasebj.2020.34.s1.05687.

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Lasserre, Rémi, Xiao-Jun Guo, Fabien Conchonaud, et al. "Raft nanodomains contribute to Akt/PKB plasma membrane recruitment and activation." Nature Chemical Biology 4, no. 9 (2008): 538–47. http://dx.doi.org/10.1038/nchembio.103.

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Murata, Michio, Shinya Hanashima, Yo Yano, et al. "Sphingomyelin Nanodomains Mainly Constitute Liquid-Ordered Phase of Ternary Model Membrane." Biophysical Journal 118, no. 3 (2020): 78a. http://dx.doi.org/10.1016/j.bpj.2019.11.600.

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Thibivilliers, Sandra, Andrew Farmer, and Marc Libault. "Biological and Cellular Functions of the Microdomain-Associated FWL/CNR Protein Family in Plants." Plants 9, no. 3 (2020): 377. http://dx.doi.org/10.3390/plants9030377.

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Membrane microdomains/nanodomains are sub-compartments of the plasma membrane enriched in sphingolipids and characterized by their unique protein composition. They play important roles in regulating plant development and plant-microbe interactions including mutualistic symbiotic interactions. Several protein families are associated with the microdomain fraction of biological membranes such as flotillins, prohibitins, and remorins. More recently, GmFWL1, a FWL/CNR protein exclusively expressed in the soybean nodule, was functionally characterized as a new microdomain-associated protein. Interestingly, GmFWL1 is homologous to the tomato FW2-2 protein, a major regulator of tomato fruit development. In this review, we summarize the knowledge gained about the biological, cellular, and physiological functions of members of the FWL/CNR family across various plant species. The role of the FWL/CNR proteins is also discussed within the scope of their evolution and transcriptional regulation.

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Jeyifous, Okunola, Eric I. Lin, Xiaobing Chen, et al. "Palmitoylation regulates glutamate receptor distributions in postsynaptic densities through control of PSD95 conformation and orientation." Proceedings of the National Academy of Sciences 113, no. 52 (2016): E8482—E8491. http://dx.doi.org/10.1073/pnas.1612963113.

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Postsynaptic density protein 95 (PSD95) and synapse-associated protein 97 (SAP97) are homologous scaffold proteins with different N-terminal domains, possessing either a palmitoylation site (PSD95) or an L27 domain (SAP97). Here, we measured PSD95 and SAP97 conformation in vitro and in postsynaptic densities (PSDs) using FRET and EM, and examined how conformation regulated interactions with AMPA-type and NMDA-type glutamate receptors (AMPARs/NMDARs). Palmitoylation of PSD95 changed its conformation from a compact to an extended configuration. PSD95 associated with AMPARs (via transmembrane AMPAR regulatory protein subunits) or NMDARs [via glutamate ionotropic receptor NMDA-type subunit 2B (GluN2B) subunits] only in its palmitoylated and extended conformation. In contrast, in its extended conformation, SAP97 associates with NMDARs, but not with AMPARs. Within PSDs, PSD95 and SAP97 were largely in the extended conformation, but had different orientations. PSD95 oriented perpendicular to the PSD membrane, with its palmitoylated, N-terminal domain at the membrane. SAP97 oriented parallel to the PSD membrane, likely as a dimer through interactions of its N-terminal L27 domain. Changing PSD95 palmitoylation in PSDs altered PSD95 and AMPAR levels but did not affect NMDAR levels. These results indicate that in PSDs, PSD95 palmitoylation, conformation, and its interactions are dynamic when associated with AMPARs and more stable when associated with NMDARs. Altogether, our results are consistent with differential regulation of PSD95 palmitoylation in PSDs resulting from the clustering of palmitoylating and depalmitoylating enzymes into AMPAR nanodomains segregated away from NMDAR nanodomains.

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Oelke, Jochen, Andreea Pasc, Achim Wixforth, Oleg Konovalov, and Motomu Tanaka. "Highly uniform, strongly correlated fluorinated lipid nanodomains embedded in biological membrane models." Applied Physics Letters 93, no. 21 (2008): 213901. http://dx.doi.org/10.1063/1.3028088.

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