• Transport occurs in membrane-bounded containers called vesicles, and several protein families have evolved to mediate the budding of a vesicle from the donor compartment, and its transport to and fusion with the target organelle. (nature.com)
  • These have been suggested to be the core machinery that mediates the fusing of two membranes, as well as ensuring that vesicles deliver their cargo to the right compartment 1 , 2 . (nature.com)
  • Finally, the enrichment of tetraspanins within secreted vesicles called exosomes, coupled with hints that tetraspanins may regulate vesicle fusion and/or fission, suggests exciting new directions for future research. (nih.gov)
  • But until now, few methods have examined the dynamic "pores" that regulate the release of cargo carried by secretory vesicles - hormone- or neurotransmitter-filled sacs - that fuse with a cell membrane. (yale.edu)
  • In vitro membrane-bound vesicles obtained by 'bisecting' (although the two parts were not always identical in size) an in vitro contractile vacuole established their own independent rounding-slackening cycles. (biologists.com)
  • Severed radial arms also became vesiculated and, like contractile vacuole membranes, these in vitro vesicles showed independent rounding-slackening cycles and vesicle-vesicle fusions. (biologists.com)
  • At least two distinct ATPases, NSF and p97, are known to be involved in the heterotypic fusion of transport vesicles with their target membranes and the homotypic fusion of membrane compartments. (elsevierpure.com)
  • In our study, we investigated the fusion between small cationic liposomes (~100 nm) and giant vesicles (tens of microns in diameter) containing increasing fractions of anionic lipids. (biophysics.org)
  • The fusion of neurotransmitter filled vesicles with the presynaptic membrane is the key step in the neuronal signaling cascade and is mediated by soluble N-ethylmaleimide-sensitive factor attachment receptor proteins (SNAREs). (uni-goettingen.de)
  • Thus they are suitable to monitor the process of content transfer through a fusion pore of added vesicles filled with a water soluble dye by means of fluorescence microscopy. (uni-goettingen.de)
  • These energy barriers determine the speed and success rate of many critical biological processes, including the fusion of highly curved membranes, for example synaptic vesicles and enveloped viruses. (haifa.ac.il)
  • Immediately after stalk expansion to the hemifusion diaphragm, the fusion pore formation energy barrier is low (15-25 k B T) due to lipid stretching in the distal monolayers and increased tension in highly curved vesicles. (haifa.ac.il)
  • The plasma membrane of the spermatid invaginated to form vesicles that were distributed among various endosomes around the CFC during spermiogenesis. (frontiersin.org)
  • Vesicles from Golgi complexes, plasma membranes and endosomes might also be the sources of the autophagosome membrane. (frontiersin.org)
  • Preparation of Impermeable Ghosts and Inside-Out Vesicles from Human Erythrocyte Membranes. (biomedcentral.com)
  • We recently developed a generic method for producing polymer-supported lipid bilayers directly from cell-derived native membrane vesicles (NMVs). (lu.se)
  • Hughson, FM 1995, ' Molecular mechanisms of protein-mediated membrane fusion ', Current Opinion in Structural Biology , vol. 5, no. 4, pp. 507-513. (princeton.edu)
  • Here we generated a series of lipopeptides derived from EK1 and found that EK1C4 was the most potent fusion inhibitor against SARS-CoV-2 S protein-mediated membrane fusion and pseudovirus infection with IC50s of 1.3 and 15.8 nM, about 241- and 149-fold more potent than the original EK1 peptide, respectively. (nature.com)
  • What is the impact of cholesterol on SARS-CoV-2 Spike protein-mediated membrane fusion? (news-medical.net)
  • When an effective fusogen anionic polymer was added to these cationic liposomes membrane fusion occurred and the functionalized liposomal membranes responded with changes in enzymatic activity thus serving as an effective nanosensory device for liposome fusion detection. (conferencedequebec.org)
  • Two populations of liposomes were prepared, both simulating the plasma membrane of target cells, but with the pH of the internal aqueous medium buffered either at pH 7.4 (physiological cytosol pH) or at pH 5.0 (endosomal pH at which influenza virus displays maximal fusion activity). (biomedcentral.com)
  • By monitoring fusion using the R18 assay, we found that the internal pH of the target liposomes did not influence membrane merging as mediated by the influenza virus hemagglutinin, thus demonstrating that a transmembrane pH gradient is not required in this fusion process. (biomedcentral.com)
  • Role of Virion M2 Protein in Influenza Virus Uncoating: Specific Reduction in the Rate of Membrane Fusion Between Virus and Liposomes by Amantadine. (biomedcentral.com)
  • Cell entry by measles virus: long hybrid receptors uncouple binding from membrane fusion. (1library.net)
  • A signal transduction system located in the cell membrane is an example of naturally occurring nanodevices in which transmission transmission among functional biomolecules such as receptors and enzymes is usually efficiently achieved in the cell membrane [5]. (conferencedequebec.org)
  • Type I angiotensin II receptors (AT1R) are somewhat unique in that they are expressed at apical (AP) and basolateral (BL) membranes in proximal tubule cells and both receptor sites undergo endocytosis. (duke.edu)
  • These results indicate that none of the integrins known to be present on mouse eggs or to be ADAM receptors are essential for sperm-egg binding/fusion, and thus, egg integrins may not play the role in gamete fusion previously attributed to them. (lu.se)
  • TNFa delivers its signals to target cells by binding to specific cell surface membrane receptors (TNFR1 and TNFR2). (cdc.gov)
  • Vesicle fusion events involved in neurotransmitter trafficking also relies on the catalytic activity of fusion proteins. (wikipedia.org)
  • The contractile vacuole of the freshwater protozoan Paramecium multimicronucleatum is a membrane-bound exocytotic vesicle that expels excess cytosolic water. (biologists.com)
  • Vesicle membranes lack the ability to fuse to one another, but will fuse to the apical plasma membrane. (niu.edu)
  • This points toward an integral membrane protein acting as a docking site for the vesicle with fusion rate possibly being controlled by phospholipase and apical plasma membrane fluidity. (niu.edu)
  • We find that the stalk formation energy decreases with curvature by up to 31 k B T in a 20-nm-radius vesicle compared with planar membranes and by up to 8 k B T in the fusion of highly curved, long, tubular membranes. (haifa.ac.il)
  • Two recent X-ray structures shed new light on the molecular mechanisms by which viral proteins mediate membrane fusion. (princeton.edu)
  • Finally, I have developed an in vitro fusion assay to enable us to dissect the functional significance of the various interactions that Vps45p displays with its cognate SNARE proteins. (gla.ac.uk)
  • Activity lasted for over 30 min at room temperature (24-27 degrees C). The rounding of the in vitro contractile vacuole corresponded to the increased membrane tension of the in vivo contractile vacuole that occurs immediately before fluid expulsion. (biologists.com)
  • The subsequent slackening of the in vitro contractile vacuole corresponded to the fluid-filling phase of the in vivo contractile vacuole that occurs at decreased membrane tension. (biologists.com)
  • An additional rounding phase of the in vitro contractile vacuole could be induced by applying suction to a portion of its membrane with a micropipette when the contractile vacuole was in its slackened phase. (biologists.com)
  • Thus, to test this hypothesis, I first devised and optimized an in vitro LE - vacuole membrane fusion assay, which relies on the assembly of complementary β-lactamase fragments to form an active enzyme upon lumenal content mixing. (concordia.ca)
  • phase transition behavior of the lipid membranes which in turn controlled receptor binding affinity toward the enzyme-inhibiting PF 573228 mediator species. (conferencedequebec.org)
  • The fusion of lipid membranes progresses through a series of hemifusion intermediates with two significant energy barriers related to the formation of stalk and fusion pore, respectively. (haifa.ac.il)
  • Interbilayer forces in membrane fusion Viral membrane fusion proteins Classification of viral fusion proteins in TCDB database Klapper R, Stute C, Schomaker O, Strasser T, Janning W, Renkawitz-Pohl R, Holz A (January 2002). (wikipedia.org)
  • I then used this biochemical assay to characterize the ions and protein machinery responsible for this fusion event. (concordia.ca)
  • The present project uses the newly developed single fusion assay based on total internal reflection (TIRF) microscopy to investigate the mechanism by which SNARE-dependent fusion is regulated by SytI, complexins, and Ca++. (grantome.com)
  • The single fusion assay makes it possible to dissect and characterize individual fusion intermediates in unprecedented detail. (grantome.com)
  • With this powerful new fusion assay, we will dissect how the fusion regulators modulate the individual fusion steps. (grantome.com)
  • The combined approach employing the single fusion assay and SDSL EPR will provide insights into mechanism whereby the synchronized release is manufactured in the neuron. (grantome.com)
  • Therefore, we herein established a SARS-CoV-2 spike (S) protein-mediated cell-cell fusion assay and found that SARS-CoV-2 showed a superior plasma membrane fusion capacity compared to that of SARS-CoV. (nature.com)
  • Substances can be transported from one membrane-encased compartment to another, but the compartments maintain their unique identities. (nature.com)
  • PSMs are continuous lipid bilayers with solid supported parts (s-PSM) as well as freestanding membranes spanning large aqueous compartments (f-PSM). (uni-goettingen.de)
  • In contrast, in the fusion of long tubular compartments, the surface tension does not accumulate due to the formation of the diaphragm, and the energy barrier for pore expansion increases with curvature by up to 11 k B T. This suggests that inhibition of polymorphic virus infection could particularly target this feature of the second barrier. (haifa.ac.il)
  • While adult somatic cells do not typically undergo membrane fusion under normal conditions, gametes and embryonic cells follow developmental pathways to non-spontaneously drive membrane fusion, such as in placental formation, syncytiotrophoblast formation, and neurodevelopment. (wikipedia.org)
  • SNARE (soluble N- ethylmaleimide-sensitive factor attachment protein receptor) assembly is the central event that may drive membrane fusion. (grantome.com)
  • Further investigation with FRET-based membrane tension and membrane-order reporters revealed a link between host cell glycolytic activity and host membrane order and tension. (ox.ac.uk)
  • We therefore have identified a connection between host cell glycolytic activity and membrane tension that influences HIV-1 fusion in real-time at the single-virus fusion level in live cells. (ox.ac.uk)
  • As glycolytic activity sets membrane tension levels by altering cellular cholesterol surface levels, our results suggest additional previously unknown benefits of cholesterol-lowering medication in HIV-1 infection. (ox.ac.uk)
  • It has been hypothesized that conserved histidines in the class II fusion protein E of these viruses function as molecular switches and, by their protonation, control the fusion process. (rupress.org)
  • here, viruses have been critical to the understanding of cellular endocytic uptake and the molecular mechanisms of membrane fusion. (elsevierpure.com)
  • The results showed six candidate fusion proteins of molecular weight 64.1, 61.7, 56.8, 43.1, 42.1, and 14.8 kDal based on their relative hydrophobicity. (niu.edu)
  • In this article, we present fusogenic nanostructures constructed from synthetic DNA which, different from previous solutions, unlock routes for modulating the rate of fusion and making it conditional to the presence of soluble DNA molecules, thus demonstrating how membrane fusion can be controlled through simple DNA-based molecular circuits. (cam.ac.uk)
  • Keywords: liposome enzyme liposome fusion self-assembly phase transition molecular device 1 Recently much effort has been devoted to developing nanoscale devices using molecules or molecular devices composed of molecular elements such as switches wires and logic gates and capable of extending current semiconductor technology to nanoscale information technology [1-4]. (conferencedequebec.org)
  • Previously we have reported on artificial cell membrane-type nanodevices employing a concept inspired by biological transmission transduction which entails a system essentially comprised of three molecular components: a synthetic receptor enzyme and liposomal membrane (Physique 1). (conferencedequebec.org)
  • This paper reports the construction of a bio-inspired molecular device that senses membrane fusion by changes in membrane-bound enzyme activity. (conferencedequebec.org)
  • Membrane fusion is one of the most fundamental processes in biological system involved in cargo transport PF 573228 through secretory pathways fertilization organelle inheritance and viral access into host cells [17-22] but there have been few reports of a molecular device sensing membrane fusion. (conferencedequebec.org)
  • Schematic illustration of the bio-inspired molecular gadget that detects liposome fusion by changing the activity of the enzymatic reaction. (conferencedequebec.org)
  • The Molecular Membrane Biology GRC is a premier, international scientific conference focused on advancing the frontiers of science through the presentation of cutting-edge and unpublished research, prioritizing time for discussion after each talk and fostering informal interactions among scientists of all career stages. (grc.org)
  • The 2023 Gordon Conference on Molecular Membrane Biology will focus on the latest insights into organelle biogenesis and function, membrane trafficking, the connection to metabolism, and interorganelle communication. (grc.org)
  • The meeting will include sessions on novel techniques and their application in molecular membrane biology, and relevance for diseases. (grc.org)
  • This GRC will be held in conjunction with the "Molecular Membrane Biology" Gordon Research Seminar (GRS). (grc.org)
  • Studies of the intracellular fusion machinery used in vesicular transport have also advanced rapidly, although high-resolution structural information is not yet available. (princeton.edu)
  • However, arachidonic acid did not influence the rate when the vesicular membrane was treated. (niu.edu)
  • Simultaneous imaging of lipid dye diffusion from the PSM into the vesicular membrane via a fusion stalk was used to quantify different fusion pathways. (uni-goettingen.de)
  • The yeast SM protein Vps45p regulates membrane fusion through the trans-Golgi / late endosomal system, and interacts directly with the syntaxin (Tlg2p) and the v-SNARE (Snc2p) proteins. (gla.ac.uk)
  • The Sec1p / Munc18 (SM) family are a conserved group of proteins that regulate membrane fusion through interactions with their cognate syntaxins. (gla.ac.uk)
  • Using the mutational analysis of recombinant subviral particles of tick-borne encephalitis virus, we provide direct experimental evidence that the initiation of fusion is crucially dependent on the protonation of one of the conserved histidines (His323) at the interface between domains I and III of E, leading to the dissolution of domain interactions and to the exposure of the fusion peptide. (rupress.org)
  • The defects (stalks or pores) attract each other via membrane-mediated capillary interactions that result in a condensation transition of the defects. (bgu.ac.il)
  • A recent study in the Biophysical Journal shows how a Dutch research group measured and visualized dynamic interactions between membranes in the presence of Ca 2+ sensors and synaptic inducers Syt1 and Doc2b. (lumicks.com)
  • used a cell-free model to assess properties associated with membrane-membrane interactions induced by Syt1 or Doc2B. (lumicks.com)
  • The researchers found that Syt1 and Ca 2+ levels independently determined the probability and strength of membrane-membrane interactions. (lumicks.com)
  • These results indicate that the approach serves to detect membrane-membrane interactions in the presence of Ca 2+ sensors. (lumicks.com)
  • The receptor and the enzyme are self-assembled around the liposomal membrane through noncovalent interactions and the enzyme's catalytic activity is usually controlled by an external signal subsequent to receptor activation PF 573228 with signal transduction mediated by metal ions. (conferencedequebec.org)
  • Invited talks will feature a broad range of topics including membrane biogenesis, protein sorting to organelles, metabolic regulation of organelle biogenesis, autophagy, protein and organelle quality control, lipid homeostasis, interorganelle contact sites, host-pathogen interactions, and the mechanism of organelle fission and fusion. (grc.org)
  • Plasmalogens may also play important roles in interactions between lipids and proteins, the transmission of chemical signals in cells, and the fusion of cell membranes. (medlineplus.gov)
  • Addgene: Designing Single-Component Optogenetic Membrane Recruitment Systems: The Rho-Family GTPase Signaling Toolbox. (addgene.org)
  • The entry of enveloped viruses into host cells involves a fusion step between the viral and a cellular membrane. (rupress.org)
  • Membrane fusion is a ubiquitous process, essential for cellular development, communication, and drug delivery. (biophysics.org)
  • Cellular fractionation experiments revealed that an unprocessed form of MexA anchored the inner membrane probably via an uncleaved signal sequence, whereas the processed form was undetectable in the membrane fraction. (elsevierpure.com)
  • Native membrane derived polymer-supported lipid bilayers (nSLBs) are poised to bridge the gap between live cell experiments and traditional model membrane architectures that by offering a combination of accessibility by surface sensitive analytical instrumentation and a composition which more closely resembles cellular membranes by displaying a diversity of endogenous membrane proteins, lipids, and carbohydrates. (lu.se)
  • and allows the aminoglycoside to ionically associate with the inner membrane ( Bryan and Van Den Elzen, 1977 ). (elifesciences.org)
  • The MexA protein is thought to be located at the inner membrane and has been assumed to link the xenobiotics-exporting subunit, MexB, and the outer membrane channel protein, OprM. (elsevierpure.com)
  • n-[9,10- 3 H]Palmitic acid incorporation experiments revealed that MexA was radiolabeled with palmitic acid, suggesting that the MexA anchors the inner membrane via the fatty acid moiety. (elsevierpure.com)
  • To evaluate the role of lipid modification and inner membrane anchoring, we substituted cysteine 24 with phenylalanine or tyrosine and tested whether or not these mutant MexAs function properly. (elsevierpure.com)
  • We concluded from these results that the MexA protein is fully functional as expressed in the periplasmic space without anchoring the inner membrane. (elsevierpure.com)
  • The SNARE family include bona fide eukaryotic fusion proteins. (wikipedia.org)
  • SNARE proteins are essential components of the machinery that facilitates membrane fusion in eukaryotic cells. (gla.ac.uk)
  • Together, these results support a model of LE - vacuole fusion that requires H+-transport by Nhx1 upstream of SNARE mediated bilayer mixing. (concordia.ca)
  • In cells, membrane fusion is mediated by SNARE proteins, whose activities are calcium-dependent. (rsc.org)
  • Die Fusion von Neurotransmitter gefüllten Vesikeln mit der präsynaptischen Membran ist der Schlüsselschritt in der neuronalen Signaltransduktion und wird durch SNARE- (soluble N-ethylmaleimide-sensitive factor attachment receptor) Proteine vermittelt. (uni-goettingen.de)
  • The interaction of the three SNARE proteins synaptobrevin 2 (syb 2), syntaxin 1A, and SNAP25 (synaptosomal associated protein of 25 kDa) is pivotal to overcome the energy barrier that leads to merging of the opposing lipid bilayers and results in the transfer of neurotransmitters across the presynaptic membrane and into the synaptic cleft. (uni-goettingen.de)
  • We propose that the first stage of membrane fusion need not be the formation of a single stalk. (bgu.ac.il)
  • Instead, we consider a scenario for defect-induced membrane fusion that proceeds cooperatively via multiple stalk formation. (bgu.ac.il)
  • Lukatsky, DB & Frenkel, D 2004, ' Multiple stalk formation as a pathway of defect-induced membrane fusion ', European Physical Journal E , vol. 14, no. 1, pp. 3-6. (bgu.ac.il)
  • Two principal fusion mechanisms are identified: the stalk mechanism, starting with the appearance of a stalk between approaching membranes, and the adhesion mechanism which involves bilayer reorganization as a result of a tight junction of the membranes. (tau.ac.il)
  • Using the expression for the elastic energy of the stalk it was possible to find the value of the spontaneous curvature of its membrane, Ks, at which the existence of a stalk is in principle possible. (tau.ac.il)
  • It is shown that, within the framework of the stalk mechanism, there exists a possibility of either the formation of a stalk of a finite radius, or complete fusion. (tau.ac.il)
  • The energy barrier of the hydrophobic interaction and the elastic energy barrier, which have to be overcome by the membranes to form the stalk are analysed. (tau.ac.il)
  • Enveloped viruses readily overcome the thermodynamic barrier of merging two plasma membranes by storing kinetic energy in fusion (F) proteins. (wikipedia.org)
  • F proteins can be independently expressed on host cell surfaces which can either (1) drive the infected cell to fuse with neighboring cells, forming a syncytium, or (2) be incorporated into a budding virion from the infected cell which leads to the full emancipation of plasma membrane from the host cell. (wikipedia.org)
  • However, on a sample to sample basis, the rate of fusion was not correlated to the absolute concentration of apical plasma membrane. (niu.edu)
  • The fusion reactions occur in a plasma, which require significant energy to create and sustain, but fusion systems are approaching the tipping point where they're beginning to generate more power than they're being supplied," Wolden said. (minesnewsroom.com)
  • Indeed, cells treated with 2-DG possessed lower plasma membrane lipid order and higher tension values, respectively. (ox.ac.uk)
  • Our novel imaging approach that combines lifetime imaging (FLIM) and SVT revealed not only changes in plasma membrane tension at the point of viral fusion, but also that HIV is less likely to enter cells at areas of higher membrane tension. (ox.ac.uk)
  • With the combined optical tweezers and confocal fluorescence microscopy configuration of the C-Trap ® , the team revealed Ca 2+ sensor-dependent mechanisms in membrane remodeling. (lumicks.com)
  • Fluorescently labeling the respective proteins and following them in real time enabled the team to validate membrane fusion mechanisms and differentiate between hemifusion or protein bridging events. (lumicks.com)
  • For more information, you can read the full article entitled " Synaptotagmin-1 and Doc2b exhibit distinct membrane remodeling mechanisms " in the Biophysical Journal . (lumicks.com)
  • It is proposed that fusion mechanisms should be classified according to the primary act involving a change in the membrane structure. (tau.ac.il)
  • While several non-native membrane fusion mechanisms have been demonstrated, few can respond to external stimuli. (rsc.org)
  • The cation channel mucolipin-1 is a bifunctional protein that facilitates membrane remodeling via its serine lipase domain. (harvard.edu)
  • It consists of consecutive steps including docking of the two bilayers, membrane destabilization, fusion of the outer leaflets (hemifusion), opening and expansion of the fusion neck and finally full fusion. (biophysics.org)
  • This finding questioned the assumption that the membrane fusion proteins connect the inner and outer membranes. (elsevierpure.com)
  • Cleavage of the Om14 (the yeast mitochondrial outer membrane protein) from E. coli OmpX (Outer membrane protein X) has provided yields of up to 70% product without detectable degradation levels. (praiseworthyprize.org)
  • J. Hoppe, H. A. Weich, W. Eichner, Preparation of Biologically Active Platelet-Derived Growth Factor Type Bb from a Fusion Protein Expressed in Escherichia coli, Biochemistry, Volume 28, (Issue 7), April 1989, Pages 2956-2960. (praiseworthyprize.org)
  • It is unclear if and where distinct membrane sources fuse during autophagosome biogenesis. (frontiersin.org)
  • Membrane fusion is critical for many biological processes, especially in eukaryotic development and viral entry. (wikipedia.org)
  • Eukaryotic genomes contain several gene families, of host and viral origin, which encode products involved in driving membrane fusion. (wikipedia.org)
  • The endocytic virus infection pathway and the involvement of low pH in triggering virus-membrane fusion were first delineated, using SFV, and this virus has remained an important tool in the study of both endocytosis and membrane fusion. (elsevierpure.com)
  • We previously developed a pan-coronavirus fusion inhibitor, EK1, which targeted the HR1 domain and could inhibit infection by divergent human coronaviruses tested, including SARS-CoV and MERS-CoV. (nature.com)
  • EK1C4 was also highly effective against membrane fusion and infection of other human coronavirus pseudoviruses tested, including SARS-CoV and MERS-CoV, as well as SARSr-CoVs, and potently inhibited the replication of 5 live human coronaviruses examined, including SARS-CoV-2. (nature.com)
  • The GP64 envelope fusion protein is an essential baculovirus protein required for cell-to-cell transmission of infection. (1library.net)
  • There has been resurgence in determining the role of host metabolism in viral infection yet deciphering how the metabolic state of single cells affects viral entry and fusion remains unknown. (ox.ac.uk)
  • We found that cells with a lower ATP:ADP ratio prior to virus addition were less permissive to virus fusion and infection. (ox.ac.uk)
  • Interestingly, cells acutely treated with glycolysis inhibitor 2-deoxyglucose (2-DG) become resistant to virus infection and also display less surface membrane cholesterol. (ox.ac.uk)
  • Our results reveal that the pH optimum of HA-driven membrane fusion of IAVs is a determinant of their sensitivity to IFN and IFITM proteins .IMPORTANCE The IFN system constitutes an important innate defense against viral infection . (bvsalud.org)
  • Entry of Semliki Forest Virus into Cells: Effects of Concanamycin A and Nigericin on Viral Membrane Fusion and Infection. (biomedcentral.com)
  • This chapter summarizes the current understanding of the life cycle of alphaviruses, focusing in particular on their entry pathway and membrane fusion activity. (elsevierpure.com)
  • The NSF-mediated fusion pathway is the best characterized, many of the components having been identified and their functions analysed. (elsevierpure.com)
  • In contrast, none of the accessory proteins for the p97-mediated fusion pathway has been identified. (elsevierpure.com)
  • We then systematically explore the relationship between lipid-membrane composition, its biophysical properties, and measured fusion efficiency, linking our observations to the stability of transition states in the fusion pathway. (cam.ac.uk)
  • To assure that the lipid-free MexA polypeptide could be unbound to the membrane, we analyzed the two- dimensional membrane topology by the gene fusion technique. (elsevierpure.com)
  • Because membrane fusion between late endosomes and vacuoles is the final event necessary for protein delivery, and because Nhx1 binds Gyp6, a Rab-GTPase activating protein that is predicted to regulate membrane fusion, I hypothesized that Nhx1 may play a role in LE - vacuole membrane fusion. (concordia.ca)
  • Here we show for the first time that the sensitivity of IAVs to the IFN-induced antiviral state and IFITM2 and IFITM3 proteins depends on the pH value at which the viral HA undergoes a conformational transition and mediates membrane fusion . (bvsalud.org)
  • The present study was designed to investigate in vivo subcellular evidence for the biogenesis of autophagosomal membrane during spermiogenesis using transmission-electron microscopy (TEM), Western blots and immunohistochemistry in samples from the Chinese soft-shelled turtle. (frontiersin.org)
  • In the present study, a subcellular mechanism for autophagosomal membrane biogenesis was examined in detail during in vivo turtle spermiogenesis. (frontiersin.org)
  • Due to the lack of detergent solubilization and reconstitution steps, the nSLBs created using this approach contain essentially all of the native lipids, as well as the membrane-associated proteins and carbohydrates from the donor membrane. (lu.se)
  • abstract = "Based on literary data, conditions necessary for membrane fusion are discussed. (tau.ac.il)
  • As a homologue of p47 exists in budding yeast, this indicates that it might also be involved in other membrane fusion reactions catalysed by p97, such as karyogamy. (elsevierpure.com)
  • Despite much progress in identifying the molecules responsible for autophagosome formation, the origin and the source of the autophagosomal membrane remain unsolved and have been the subject of long-standing debate. (frontiersin.org)
  • These molecules are found in cell membranes throughout the body. (medlineplus.gov)
  • Measuring light intensity around artificial fusion events, Erdem Karatekin of the Nanobiology Institute at West Campus, and collaborators at Columbia University have calculated the size and length of time these pores open and close. (yale.edu)
  • Neither artificial membrane slabs, nor 'live cells' imaged under conditions in which cells have a shabby life that doesn't last long (how much of this is due to the mistreatment of the membrane proteins? (biophysics.org)
  • The adherence and merging of cell membranes, intracellular membranes, or artificial membranes to each other or to viruses, parasites, or interstitial particles through a variety of chemical and physical processes. (bvsalud.org)
  • d Images of SARS-CoV and SARS-CoV-2 S-mediated cell-cell fusion on 293T/ACE2 cells at 2 h (left) and 24 h (right). (nature.com)
  • Purified GST fusion proteins of the N and C termini of Na v 1.3 pull down contactin from lysates of transfected HEK 293 cells. (jneurosci.org)
  • Addition of cholesterol in these in glycolytically-inactive cells rescued the virus entry block at hemifusion and enabled completion of HIV-1 fusion. (ox.ac.uk)
  • The discovery of membrane fusion shows the means by which proteins and other materials are transported within and between cells. (talkingpointsmemo.com)
  • In A549 and Calu-3 cells , viruses displaying a higher pH optimum of HA-mediated membrane fusion , H5N1-PR8 and H7N9-PR8, were less sensitive to the IFN-induced antiviral state than their counterparts with HAs from duck and human viruses , which fused at a lower pH . (bvsalud.org)
  • Furthermore, similar effects of the viral fusion pH on IFN sensitivity were observed in experiments with (i) primary human type II alveolar epithelial cells and differentiated cultures of human airway epithelial cells , (ii) nonrecombinant zoonotic and pandemic IAVs, and (iii) preparations of IFN-α and IFN-λ1. (bvsalud.org)
  • A higher pH of membrane fusion and reduced sensitivity to IFN correlated with lower restriction of the viruses in MDCK cells stably expressing the IFN-inducible transmembrane proteins IFITM2 and IFITM3, which are known to inhibit viral fusion. (bvsalud.org)
  • Syncytin-1 Syncytin-2 ERV3 is not functional in humans HAP2 is a domesticated viral class II fusion protein found in diverse eukaryotes including Toxoplasma, vascular plants, and fruit flies. (wikipedia.org)
  • Our data imply that the high pH optimum of membrane fusion typical of zoonotic IAVs of gallinaceous poultry , such as H5N1 and H7N9, may contribute to their enhanced virulence in humans . (bvsalud.org)
  • Apical membranes were isolated from the homogenate by a step- gradient and differential centrifugation. (niu.edu)
  • Therefore, apical membrane is apparently required for fusion but it does not control the overall rate. (niu.edu)
  • The fusion rate may be regulated by the membrane lipid environemnt as shown by an increase in fusion capacity after arachidonic acid treatment of the apical membrane. (niu.edu)
  • The peptide regions required to drive fusion are formed from the turns between the β-sheets. (wikipedia.org)
  • Moreover, peptide sequences within the AT1R-COOH tail necessary for endocytosis also modulate endosomal fusion properties. (duke.edu)
  • Fusion pathways are also involved in the development of musculoskeletal and nervous system tissues. (wikipedia.org)
  • There are four groups of fusion proteins categorized by their structure and mechanism of fusion. (wikipedia.org)
  • A Common Mechanism for Influenza Virus Fusion Activity and Inactivation. (biomedcentral.com)
  • However, these stresses relax over time due to lipid flip-flop from the proximal monolayer, resulting in a larger hemifusion diaphragm and a higher fusion pore formation energy barrier, up to 35 kBT. (haifa.ac.il)
  • Post-transcriptional modifications made to the fusion proteins by the host, namely addition and modification of glycans and acetyl groups, can drastically affect fusogenicity (the ability to fuse). (wikipedia.org)
  • Fusion is not unlike the processes that occur in the Sun - tritium and deuterium, isotopes of hydrogen, fuse together to create helium, which is accompanied by a very small loss of mass but an enormous release of energy in accordance with Einstein's famous relation E = mc 2 ," Wolden said. (minesnewsroom.com)
  • The flavivirus membrane fusion machinery, like that of many other enveloped viruses, is triggered by the acidic pH in endosomes after virus uptake by receptor-mediated endocytosis. (rupress.org)
  • Membrane fusion proteins (not to be confused with chimeric or fusion proteins) are proteins that cause fusion of biological membranes. (wikipedia.org)
  • Membrane fusion is a ubiquitous phenomenon linked to many biological processes, and represents a crucial step in liposome-based drug delivery strategies. (cam.ac.uk)
  • Fusion has the potential to be an unlimited carbon-free power supply, said Colin Wolden, professor of chemical and biological engineering at Mines and lead investigator on the project. (minesnewsroom.com)
  • Wolden and Mines collaborator Doug Way, professor emeritus of chemical and biological engineering, have developed composite metal membranes for high-temperature hydrogen separations employed in conventional petrochemical refining operations. (minesnewsroom.com)
  • Fluorescence Method for Measuring the Kinetics of Fusion Between Biological Membranes. (biomedcentral.com)
  • Recent years have seen strong research efforts on the lipid component of biological membranes. (lu.se)
  • In my talk, I will show you some examples how such biological cues influence the dynamic properties of membranes. (lu.se)
  • This dissertation reports the function of Nhx1, an endosomal Na+ (K+)/H+ exchanger, in late endosome - vacuole membrane fusion in the model eukaryote S. cerevisiae. (concordia.ca)
  • They are found in reoviruses, which are non-enveloped viruses and are specialized for cell-cell rather than virus-cell fusion, forming syncytia. (wikipedia.org)
  • Is the Subject Area "Cell membranes" applicable to this article? (plos.org)
  • The explosion of information in modern cell biology has in many cases been fostered by the use of viruses as experimental paradigms Subjects as wide ranging as RNA splicing, DNA replication, on cogenes, cell polarity, and membrane protein biosynthesis have all taken advantage of the experimental manipulability, high signal-to-noise ratio, and defined components of virus systems. (elsevierpure.com)
  • Fig. 1: Establishment of SARS-CoV-2 S protein-mediated cell-cell fusion system. (nature.com)
  • The study demonstrates how combining optical tweezers and live imaging in a cell-free model offers functional insights into membrane fusion that are unattainable by existing approaches. (lumicks.com)
  • An Elegant Excuse to Spend a Week Discussing Intriguing Cell Membranes! (biophysics.org)
  • These results indicated a relationship between host metabolic state and the likelihood for virus-cell fusion to occur. (ox.ac.uk)
  • Virus-Cell and Cell-Cell Fusion. (biomedcentral.com)
  • As cell membranes are both dynamic and compositionally complex, replicating these aspects in a model membrane are essential. (lu.se)
  • Further, the present project uses site-directed spin labeling (SDSL) and electron paramagnetic resonance (EPR), an established technique for the investigation of structures and topologies of membrane proteins. (grantome.com)
  • Coronaviruses have at least four major structural proteins, including spikes (S), membranes (M), envelopes (E), and nucleocapsid (N) proteins. (medsci.org)
  • By bringing phospholipid bilayer-coated beads into contact and subsequently pulling them apart, they could measure membrane-membrane interaction probabilities and strength in the presence of these proteins. (lumicks.com)
  • The origin and evolution of the monolayer and bilayer stalks between membranes are analysed. (tau.ac.il)
  • Modulating membrane fusion through the design of fusogenic DNA circuits and bilayer composition. (cam.ac.uk)
  • Finally, we observe that specific lipid compositions lead to the emergence of complex bilayer architectures in the fusion products, such as nested morphologies, which are accompanied by alterations in biophysical behaviour. (cam.ac.uk)
  • Fusion proteins can originate from genes encoded by infectious enveloped viruses, ancient retroviruses integrated into the host genome, or solely by the host genome. (wikipedia.org)
  • They are the only known membrane fusion proteins found in non-enveloped viruses. (wikipedia.org)
  • pH Optimum of Hemagglutinin-Mediated Membrane Fusion Determines Sensitivity of Influenza A Viruses to the Interferon-Induced Antiviral State and IFITMs. (bvsalud.org)
  • Target Membrane Sialic Acid Modulates both Binding and Fusion Activity of Influenza Virus Biochim . (biomedcentral.com)
  • Unfortunately, there are no existing assays that directly measure this fusion event. (concordia.ca)