... viral fusion proteins MeSH D12.776.964.970.880.910.330 - hiv envelope protein gp41 MeSH D12.776.964.970.880.940 - viral matrix ... hemagglutinins, viral MeSH D12.776.964.970.880.345.500 - hemagglutinin glycoproteins, influenza virus MeSH D12.776.964.970. ... viral core proteins MeSH D12.776.964.970.600.850.350 - gene products, gag MeSH D12.776.964.970.600.850.350.325 - fusion ... fusion proteins, gag-onc MeSH D12.776.964.775.350.320.700 - oncogene protein p65(gag-jun) MeSH D12.776.964.775.350.325 - fusion ...
... also known as the fusion peptide that is eventually responsible for fusion between viral and host membrane, is hidden in a ... The first three hemagglutinins, H1, H2, and H3, are found in human influenza viruses. By phylogenic similarity, the HA proteins ... Secondly, once bound it facilitates the entry of the viral genome into the target cells by causing the fusion of host endosomal ... Secondarily, HA is responsible for the fusion of the viral envelope with the late endosomal membrane once exposed to low pH ( ...
... thereby blocking HA from harpooning a sticky fusion peptide into the host membrane during viral entry. The FI6 provides ... "A neutralizing antibody selected from plasma cells that binds to group 1 and group 2 influenza A hemagglutinins". Science ... A stalk domain connects the head to the viral membrane and is responsible for fusing viral and host membranes so that the ... Sitting atop the HA spike is a globular head domain that binds to cellular receptors during viral entry and contains the major ...
The research required every year to isolate a potential popular viral strain and create a vaccine to defend against it is a six ... Stalking influenza by vaccination with pre-fusion headless HA mini-stem. 2016 BBC: 'Super antibody' fights off flu "Scientists ... By vaccinating twice with hemagglutinins that have different "heads" but the same membrane-proximal "stalk", the immune system ... Krammer F (May 2017). "Strategies to induce broadly protective antibody responses to viral glycoproteins". Expert Review of ...
They bind viral ligands such as hemagglutinins and hemagglutinin neuraminidases, some bacterial ligands and cellular ligands ... The NKG2D-Fc fusion proved capable of reducing tumor growth and prolonging survival of the recipients. In a transplantation ... As these are stress molecules released by cells upon viral infection, they serve to signal to the NK cell the presence of viral ... Lodoen MB, Lanier LL (2005). "Viral modulation of NK cell immunity". Nature Reviews Microbiology. 3 (1): 59-69. doi:10.1038/ ...
They bind viral ligands such as hemagglutinins and hemagglutinin neuraminidases, some bacterial ligands and cellular ligands ... The NKG2D-Fc fusion proved capable of reducing tumor growth and prolonging survival of the recipients. In a transplantation ... As these are stress molecules released by cells upon viral infection, they serve to signal to the NK cell the presence of viral ... MHC class I molecules are the main mechanism by which cells display viral or tumor antigens to cytotoxic T cells. A common ...
... which promotes by cooperation of NH with the viral fusion protein (F). To perform the fusion function F protein must be ... Arnon TI, Lev M, Katz G, Chernobrov Y, Porgador A, Mandelboim O (September 2001). "Recognition of viral hemagglutinins by NKp44 ... This cleavage promotes the fusion of the viral lipid envelope with the cell outer membrane. In the lipid envelope of the virus ... This cleavage triggers the fusion process of viral envelope and cell membrane, ...
At this point, the viruses have been weakened or killed and the viral antigen is purified and placed inside vials, syringes, or ... May 1993). "A common neutralizing epitope conserved between the hemagglutinins of influenza A virus H1 and H2 strains". Journal ... as fusion proteins, mounted on virus-like particles, on non-pathogenic viruses, as DNA, and others), are under development. ... The vaccine comes in inactive and weakened viral forms. The live, weakened vaccine is generally not recommended in pregnant ...
... and fusion of the viral membrane to the endosome during viral entry and neuraminidase (NA), the proteins that cleaves sialic ... An epitope shared from the hemagglutinins of H1, H2, H5, and H6 subtypes of influenza A disease. Acta Virol. 1999;43:237C244. [ ... and fusion of the viral membrane to the endosome during viral access and neuraminidase (NA), the protein that cleaves sialic ... 3 and the MAbs bound to a conserved epitope in the stem region of the HA containing the fusion peptide (Shape 1). The fusion ...
Hemagglutinins, Viral. *Viral Fusion Proteins. *N-Acetylneuraminic Acid. *Parechovirus. *Paramyxoviridae Infections. * ...
Influenza is the prototypic virus containing a class I fusion protein, hemagglutinin, that requires low pH for fusion. ... The viral hemagglutinin was genetically fused to ferritin, a protein that naturally forms nanoparticles composed of 24 ... Most consist of a viral protein called hemagglutinin, which has the unique ability to latch onto respiratory cells and invade ...
  • For example, the proportion of hemagglutinins on a virus particle that insert into the cell membrane affects how fast fusion occurs and how sensitive the virus is to attack by host immune-system proteins called antibodies. (elifesciences.org)
  • The influenza hemagglutin (HA) is the best studied and most thoroughly characterized of the viral fusion proteins. (elifesciences.org)
  • Crystallographic studies have shown that the coiled-coil motif occurs in several viral membrane-fusion proteins, including HIV-1 gp41 and influenza virus hemagglutinin. (princeton.edu)
  • Here, the LearnCoil-VMF program was designed as a specialized program for identifying coiled-coil-like regions in viral membrane-fusion proteins. (princeton.edu)
  • Based upon the use of LearnCoil-VMF, as well as other computational tools, we report detailed sequence analyses of coiled-coil-like regions in retrovirus, paramyxovirus and filo-virus membrane-fusion proteins. (princeton.edu)
  • Complementing previous crystallographic studies, the coiled-coil-like regions detected by LearnCoil-VMF provide further evidence that the three-stranded coiled coil is a common motif found in many diverse viral membrane-fusion proteins. (princeton.edu)
  • Kim, Peter S. / LearnCoil-VMF : Computational evidence for coiled-coil-like motifs in many viral membrane-fusion proteins . (princeton.edu)
  • These results illustrate the relationship between degradation of viral proteins in the cytoplasm of an infected cell and recognition of epitopes at the cell surface by class I-restricted T cells. (ox.ac.uk)
  • Attention is focused in this review on viral proteins that are known to mediate or influence virus-induced cell fusion. (springer.com)
  • Because these proteins also mediate or influence entry of virus into cells, the virion-cell fusion required for this entry is discussed as well. (springer.com)
  • Viral Fusion Proteins" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) . (umassmed.edu)
  • Proteins, usually glycoproteins, found in the viral envelopes of a variety of viruses. (umassmed.edu)
  • This graph shows the total number of publications written about "Viral Fusion Proteins" by people in this website by year, and whether "Viral Fusion Proteins" was a major or minor topic of these publications. (umassmed.edu)
  • Below are the most recent publications written about "Viral Fusion Proteins" by people in Profiles. (umassmed.edu)
  • Membrane Fusion Proteins" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) . (umassmed.edu)
  • Below are the most recent publications written about "Membrane Fusion Proteins" by people in Profiles. (umassmed.edu)
  • A conserved histidine in Group-1 influenza subtype hemagglutinin proteins is essential for membrane fusion activity. (harvard.edu)
  • Three viral surface proteins are embedded in the cell-derived virion membrane: HA, neuraminidase (NA) and the M2 proton channel protein. (deepdyve.com)
  • The batMuV F and HN proteins were successfully incorporated into viral particles and the resultant chimeric virus was able to mediate infection of Vero cells. (microbiologyresearch.org)
  • Functional properties and genetic relatedness of the fusion and hemagglutinin-neuraminidase proteins of a mumps virus-like bat virus. (tiho-hannover.de)
  • The increased binding was functional, was not dependent on the interaction with viral hemagglutinin-neuraminidase, was not dependent on the glycosylation site, and was not abolished after mutating the transmembrane or cytosolic portions of the class I MHC proteins. (jimmunol.org)
  • While antibodies to the immunodominant, but highly variable, regions of HA and NA can provide potent virus strain-specific protection, the existence of weaker and more broadly protective immune activities directed to less variable regions of viral proteins has long been known ( 5 ). (cdc.gov)
  • Serebryakova MV, Kordyukova LV, Rudneva IA, Kropotkina EA, Veit M, Baratova LA. Mass spectrometry analysis of influenza virus reassortant clones does not reveal an influence of other viral proteins on S-acylation of hemagglutinin. (fu-berlin.de)
  • Cleaved HA proteins bind to cell receptor and then are endocytosed into the endosome where they undergo conformational changes and exposure of fusion peptide on HA2 subunit under low pH. (hindawi.com)
  • From a diagnostics point of view, aptamers are being designed as a bio-recognition element in diagnostic systems to detect viral proteins either in the blood (serum or plasma) or into infected cells. (mediaatlas.si)
  • Another potential use of aptamers is for therapeutics of viral infections, interfering in the interaction between the virus and the host using aptamers targeting host-cell matrix receptors, or attacking the virus intracellularly, targeting proteins implicated in the viral replication cycle. (mediaatlas.si)
  • In this paper, we review how aptamers working against viral proteins are discovered, with a focus on recent advances that improve the aptamers' properties as a real tool for viral infection detection and treatment. (mediaatlas.si)
  • In in vitro experiments, ClO 2 denatured viral envelope proteins (haemagglutinin and neuraminidase) that are indispensable for infectivity of the virus, and abolished infectivity. (microbiologyresearch.org)
  • Taken together, we conclude that ClO 2 gas is effective at preventing aerosol-induced influenza virus infection in mice by denaturing viral envelope proteins at a concentration well below the permissible exposure level to humans. (microbiologyresearch.org)
  • Universal antibodies against the highly conserved influenza fusion peptide cross-neutralize several subtypes of influenza A virus. (nih.gov)
  • We previously reported that antibodies targeting the first 14 amino acids of the N-terminus of the fusion peptide could bind to virtually all influenza virus strains and quantify hemagglutinins in vaccines produced in embryonated eggs. (nih.gov)
  • Here we demonstrate that these universal antibodies bind to the viral hemagglutinins in native conformation presented in infected mammalian cell cultures and neutralize multiple subtypes of virus by inhibiting the pH-dependant fusion of viral and cellular membranes. (nih.gov)
  • These results suggest that this unique, highly-conserved linear sequence in viral hemagglutinin is exposed sufficiently to be attacked by the antibodies during the course of infection and merits further investigation because of potential importance in the protection against diverse strains of influenza viruses. (nih.gov)
  • Li C, Jaentschke B, Song Y, Wang J,Cyr TD, Van Domselaar G, He R, Li X (2009) A simple slot blot for the detection of virtually all subtypes of the influenza A viral hemagglutinins using universal antibodies targeting the fusion peptide. (umanitoba.ca)
  • Chun S, Li C, Van Domselaar G, Wang J, Farnsworth A , Cui X, Rode H, . Cyr TD, He R. and Li X. (2008) Universal antibodies and their applications to the quantitative determination of virtually all subtypes of the influenza A viral hemagglutinins. (umanitoba.ca)
  • Iorio, Ronald M. and Glickman, Rhona L., "Fusion mutants of Newcastle disease virus selected with monoclonal antibodies to the hemagglutinin-neuraminidase" (1992). (umassmed.edu)
  • Published data on fusion inhibition by antibodies to the 'stem' of influenza virus hemagglutinin (HA) now allow us to incorporate into simulations the provision that some HAs are inactive. (elifesciences.org)
  • Immunization of mice with low pH treated viral vaccine induced lower levels of homologous or heterologous virus-specific binding and neutralizing antibodies compared to the untreated vaccine. (pubmedcentralcanada.ca)
  • A simple slot blot for the detection of virtually all subtypes of the influenza A viral hemagglutinins using universal antibodies targeting the fusion peptide. (innovation.ca)
  • Through a different approach, it was possible the production of antibodies of broad spectrum, which can recognize many Hemagglutinins of different virus. (bvsalud.org)
  • Antibodies able to recognize 8 in 16 known hemagglutinins were discovered, comprising the most common antibodies in humans (and consequently more relevant), as H1 and H5. (bvsalud.org)
  • Unfortunately, the H3, H7 and HAs of important viruses are not recognized by these antibodies because they belong to the second group of HAs, the group 2, which has a different fusion peptide. (bvsalud.org)
  • On the other hand, it was not found any mutant H5N1 virus which was not neutralized by the antibodies in the tests performed, reinforcing the importance of the virus fusion region. (bvsalud.org)
  • Material and methods: An 8-mer solid- phase (TG resin) library was screened with a neutralising and protective RSV fusion protein specific monoclonal antibodies (Mab-19). (tudelft.nl)
  • Conclusions: This report demonstrates for the first time that: (1) a protective epitope of the conserved RSV fusion protein can be mimicked by synthetic peptides: and (2) immunisations with these mimotopes induced specific anti-RSV neutralising antibodies and reduced vital load in vivo. (tudelft.nl)
  • Immunization of BALB/c mice with these mimotopes, presented as MAPs, resulted in the induction of anti-peptide antibodies that inhibited the binding of MAb 19 to RSV and neutralized viral infection in vitro, with titers equivalent to those in sera from RSV-infected animals. (tudelft.nl)
  • Immunization induced antibodies that bound to recombinant HA protein and viral particles, and competed with CR9114 for binding to the HA stem. (scienceopen.com)
  • Hemagglutinin (HA) is the receptor-binding and membrane fusion glycoprotein of influenza virus and the target for infectivity-neutralizing antibodies. (scienceopen.com)
  • Importantly, systemic immunization by the post-fusion HA antigen results in GC B cells targeting the occluded epitope, and induces a class of protective antibodies that have cross-group specificity and afford protection independent of virus neutralization activity. (nature.com)
  • Our results identify a class of cross-protective antibodies that are selected at the viral replication site, and provide insights into vaccine strategies using the occluded epitope. (nature.com)
  • Thus, typical HA-specific antibodies neutralize viral infectivity and fully protect against infection when they are present at sufficient concentration in the lining fluid of the respiratory tract, and typical NA-specific antibodies inhibit the release of newly formed virus from infected host cells and thus limit the spread and shedding of virus during infection. (cdc.gov)
  • The RSV fusion glycoprotein (F) is a conserved target of neutralizing antibodies ( 7 ), including Palivizumab and the closely related monoclonal antibody, Motavizumab ( 8 ). (pnas.org)
  • The spread of IC323- F(T461I)-EGFP was inhibited by a fusion inhibitor peptide as well as by some but not all of the anti-hemagglutinin antibodies which neutralize SLAM- or nectin-4- dependent MV infection, suggesting the presence of a distinct neuronal receptor. (elsevier.com)
  • However, the virus has immunogenic regions in the viral envelope glycoproteins that are associated with viral escape or non-neutralizing antibodies. (frontiersin.org)
  • Four monoclonal antibodies against the viral hemagglutinin had the ability to decrease the expression of the phosphoprotein, fusion, and membrane protein. (scripps.edu)
  • Viral Neuraminidase is one of two major glycoproteins found on the surface of influenza viral membranes, the other being hemagglutinin . (proteopedia.org)
  • Recombinant modified vaccinia virus Ankara (MVA), encoding the measles virus (MV) fusion (F) and hemagglutinin (H) (MVA-FH) glycoproteins, was evaluated in an MV vaccination-challenge model with macaques. (eur.nl)
  • Like many other viral glycoproteins, the hemagglutinin (HA) of influenza viruses is activated by proteolytic cleavage. (springer.com)
  • Membrane glycoproteins from influenza viruses which are involved in hemagglutination, virus attachment, and envelope fusion. (harvard.edu)
  • Since all efforts to isolate infectious batMuV have reportedly failed, we generated recombinant mumps viruses (rMuVs) in which the open reading frames (ORFs) of the fusion (F) and haemagglutinin-neuraminidase (HN) glycoproteins of an hMuV strain were replaced by the corresponding ORFs of batMuV. (microbiologyresearch.org)
  • Current influenza virus vaccines attempt to induce strong antibody responses against the viral glycoproteins hemagglutinin (HA) and, with lesser emphasis, neuraminidase (NA) because their protective efficacy is well documented. (cdc.gov)
  • The basic features of RSV F are shared with the fusion glycoproteins of other members of the Paramyxoviridae, such as parainfluenza virus 3 (PIV3), PIV5, and Newcastle disease virus (NDV). (pnas.org)
  • During cell entry, F glycoproteins undergo a conformational change that brings the viral and cellular membranes into proximity, ultimately leading to their fusion ( 9 ). (pnas.org)
  • The SU portion of the viral glycoprotein harbors the determinants of the specificity of the virus for its cognate cellular receptor and therefore is vital to viral tropism. (hubpages.com)
  • The SU portion of the glycoprotein is entirely located on the outside of the viral membrane. (hubpages.com)
  • Retrovirus infection is initiated by the binding of the surface (SU) portion of the viral envelope glycoprotein to specific cellular receptors expressed on the cell surface. (hubpages.com)
  • Hemagglutinin (HA) is the major surface envelope glycoprotein on influenza virus, and responsible for essential viral functions, such as binding to host receptors, viral entry, and membrane fusion ( 31 ). (asm.org)
  • and Griffin, Diane E., "Successful DNA immunization against measles: neutralizing antibody against either the hemagglutinin or fusion glycoprotein protects rhesus macaques without evidence of atypical measles" (2000). (umassmed.edu)
  • The hemagglutinin (HA) glycoprotein of influenza viruses is posttranslationally cleaved into the disulfide-linked subunits HA 1 and HA 2 , and this proteolytic processing event is critical to the virus life cycle as it is required to activate membrane fusion potential and virus infectivity. (springer.com)
  • Vaccine candidates based on a chief RSV neutralization antigen, the fusion (F) glycoprotein, have foundered due to problems with stability, purity, reproducibility, and potency. (pnas.org)
  • RSV F is a membrane anchored glycoprotein that mediates viral entry into host cells. (pnas.org)
  • Wang M, Ludwig K, Böttcher C, Veit M. The role of stearate attachment to the hemagglutinin-esterase-fusion glycoprotein HEF of influenza C virus. (fu-berlin.de)
  • The kinetics of conformational changes were compared with those of the fusion of influenza virus with red blood cell membranes as assessed by the R18-dequenching assay. (biomedsearch.com)
  • The highly conserved first 23 residues of the influenza hemagglutinin HA2 subunit constitute the fusion domain, which plays a pivotal role in fusing viral and host-cell membranes. (nih.gov)
  • The TM subunit functions to anchor the complex into the viral envelope and is critical for fusion between cellular and viral membranes. (hubpages.com)
  • In the normal fusion pathway, hemifusion is transient and is not accompanied by any measurable transfer of lipid probes between the membranes. (mblwhoilibrary.org)
  • During this process, hemagglutinin molecules insert into the target cell membrane to bring together the viral and cellular membranes. (elifesciences.org)
  • Binding of H protein to the receptor induces a conformational change that allows the F protein to trigger virion/cell membranes fusion. (uniprot.org)
  • HA plays a key role in the infection process, binding to receptors on the host cell surface and mediating the fusion between viral and host endosomal membranes. (pku.edu.cn)
  • This particle plays two crucial functions in the viral life cycle: it allows for the attachment of the virus into the host cell and participates in the fusion of the virus and host membranes. (edu.pl)
  • For the fusion site in the stalk to be functional, the HA 0 primary protein must first be activated by proteolytic cleavage into the HA 1 and HA 2 subunits, which remain coupled by disulfide bonds, thereby facilitating the conformational change of HA necessary for fusion of the viral and cellular membranes ( 18 ). (asm.org)
  • Influenza infection is initiated by binding of HA1 to its host cell receptors and followed by the fusion between viral and host endosomal membranes mediated by HA2. (scirp.org)
  • This innovative approach may provide a useful alternative to quantitative determination of all viral hemagglutinin and neuraminidase. (jove.com)
  • Once the viral particle is formed, Neuraminidase cleaves the terminal sialic (neuraminic) acid residues from the glycan structures on the surface of the infected cell, breaking the hemmaglutinin-glycan interaction and promoting release of the viral particle to infect other cells. (proteopedia.org)
  • This prevents neuraminidase from cleaving the hemmaglutinin-glycan tethers and releasing the viral cargo after viral replication. (proteopedia.org)
  • Varghese JN, McKimm-Breschkin JL, Caldwell JB, Kortt AA, Colman PM. The structure of the complex between influenza virus neuraminidase and sialic acid, the viral receptor. (proteopedia.org)
  • L1, a neuraminidase (NA)-deficient virus derived from AV, has the opposite fusion phenotype from the wild-type virus. (umassmed.edu)
  • Morbiliviruses hemagglutinins have no neuraminidase activity. (uniprot.org)
  • We have recently demonstrated that the viral hemagglutinin (HA) 3 protein of influenza virus and the HA-neuraminidase (HN) protein of Sendai virus (SV) can interact with both the NKp44 and NKp46 receptors and that this interaction leads to increased killing that can overcome the class I MHC-mediated inhibition ( 4 , 5 ). (jimmunol.org)
  • These regions confer specificity to different receptors and this specific interaction is the major determinant of the tropism of retroviruses as cells lacking the receptor are nonpermissive for viral entry. (hubpages.com)
  • For the natural cytotoxicity receptors, viral hemagglutinins have been identified as ligands that bind NKp46 and NKp44 ( 10 ), triggering lysis of infected cells. (jimmunol.org)
  • The alteration in receptor-binding affinity results in a decreased potential for elution from cellular receptors and correlates with an increased ability to promote both modes of fusion. (umassmed.edu)
  • We describe interactions between the S protein and cellular receptors, co-receptors, and antagonists, as well as a hypothetical mechanism of the homotrimeric spike structure destabilization that triggers the fusion of the viral envelope with the cell membrane at physiological pH and mediates the viral nucleocapsid entry into the cytoplasm. (bvsalud.org)
  • Influenza A viruses (IAVs) initiate infection by attaching Hemagglutinin (HA) on the viral envelope to sialic acid (SA) receptors on the cell surface. (bvsalud.org)
  • Here, we characterize the influenza virus coat protein hemagglutinin (HA), which binds to host cell surface glycan receptors containing sialic acid (SA) and subsequently mediates virus uptake, membrane fusion, and infection. (asm.org)
  • Moreover, a membrane-anchored designated receptor efficiently triggered fusion, provided that it engaged the H dimer at locations proximal to where the natural receptors bind and distal to the H-dimer interface. (elsevier.com)
  • We discuss how receptors may force H-protein heads to switch partners and transmit the fusion-triggering signal. (elsevier.com)
  • Secondly, once bound it facilitates the entry of the viral genome into the target cells by causing the fusion of host endosomal membrane with the viral membrane. (wikipedia.org)
  • Despite the high variability of its genome, the structure of viral RNA (vRNA) possesses features that remain constant between strains and are biologically important for virus replication. (bvsalud.org)
  • Considering the RNA nature of the influenza viral genome, a mutation in hemagglutinin (HA) gene which led to change in antigenicity of the strains circulating during those epidemic periods is anticipated. (biomedcentral.com)
  • Eighteen bovine viral diarrhea viruses (BVDV) from cattle in China between 2005 and 2008 were genetically typed by sequencing of the 5′-untranslated region (5′-UTR) of the viral genome and for selected isolates the Npro region. (usda.gov)
  • This process, termed antigenic drift, results from the high mutation rate of the viral genome and the continuous selection of mutants with improved replication characteristics in the immune human host population. (cdc.gov)
  • NCL is in cellular fractions containing the HIV genome, viral matrix and reverse transcriptase in addition to in complexes with CD4 and CXCR4/CCR5 at the cell membrane. (mediaatlas.si)
  • Specifically, the HA1 domain of the protein binds to the monosaccharide sialic acid which is present on the surface of its target cells, allowing attachment of viral particle to the host cell surface. (wikipedia.org)
  • Role of the two sialic acid binding sites on the newcastle disease virus HN protein in triggering the interaction with the F protein required for the promotion of fusion. (umassmed.edu)
  • Instead of the sialic acid bonding site, they attack the fusion peptide, HA region which is inserted in the cell and makes the fusion of the viral membrane with the endosome membrane , a cell structure which allows the entry of the influenza virus. (bvsalud.org)
  • Characterization of the sialic acid binding activity of influenza A viruses using soluble variants of the H7 and H9 hemagglutinins. (tiho-hannover.de)
  • The importance of viral receptor-binding hemagglutinins and host sialic acid distribution in species-restricted binding of viruses is underscored. (springer.com)
  • We demonstrate that at low pH, where the fusion process is triggered, the native peptide transiently visits activated states that are very similar to those sampled by a G8A mutant. (nih.gov)
  • The fusion peptide of influenza viral hemagglutinin plays a critical role in virus entry by facilitating membrane fusion between the virus and target cells. (nih.gov)
  • As the fusion peptide is the only universally conserved epitope in all influenza A and B viruses, it could be an attractive target for vaccine-induced immune responses. (nih.gov)
  • At neutral pH, the 23 residues near the N-terminus of HA2, also known as the fusion peptide that is eventually responsible for fusion between viral and host membrane, is hidden in a hydrophobic pocket between the HA2 trimeric interface. (wikipedia.org)
  • First, fusion peptide is released from the hydrophobic pocket and HA1 is dissociated from HA2 domain. (wikipedia.org)
  • These findings lead to a model for the fusogenic conformation of HA: the coiled-coil stem of the native state extends, relocating the hydrophobic fusion peptide, by 100 A, toward the target membrane. (nih.gov)
  • Bosch FX, Garten W, Klenk HD, Rott R. Proteolytic cleavage of influenza virus hemagglutinins: primary structure of the connecting peptide between HA1 and HA2 determines proteolytic cleavability and pathogenicity of Avian influenza viruses. (springer.com)
  • This so-called "fusion peptide" acts like a molecular grappling hook by inserting itself into the endosomal membrane and locking on. (bionity.com)
  • As the cell membrane has specific properties, the fusion peptide needs to be much conserved and any change implies in loss of function. (bvsalud.org)
  • In the work described here, a combinatorial solid-phase peptide library was screened with a protective monoclonal antibody (MAb 19) to identify peptide mimics (mimotopes) of a conserved and conformationally-determined epitope of RSV fusion (F) protein. (tudelft.nl)
  • activation requires its extrusion towards the fusion target membrane, as the N terminus of a newly formed trimeric coiled coil, and repositioning of the C-terminal membrane anchor near the fusion peptide at the same end of a rod-shaped molecule. (scienceopen.com)
  • The resulting N terminus of F1 harbors a hydrophobic fusion peptide responsible for cellular membrane insertion, and the C terminus of F1 is anchored in the viral membrane by virtue of the transmembrane (TM) region. (pnas.org)
  • Then, the fusion peptide is inserted into the cell membrane and mediates the formation of fusion pore [ 13 , 14 ]. (hindawi.com)
  • Cleavage which is necessary for the fusion activity of the hemagglutinin and thus for the infectivity of the virus is exerted by host cell proteases, and the presence of an appropriate enzyme determines whether infectious virus is made in a given cell. (springer.com)
  • Wei Y, Zhang Y, Cai H, Mirza AM, Iorio RM, Peeples ME, Niewiesk S, Li J. Roles of the putative integrin-binding motif of the human metapneumovirus fusion (f) protein in cell-cell fusion, viral infectivity, and pathogenesis. (umassmed.edu)
  • The ability of MAbs to block the conformational change of HA at the low pH of the endosomal compartment appears to be the key attribute of stalk-binding neutralizing MAbs responsible for preventing influenza viral infectivity ( 19 ). (asm.org)
  • The hemagglutinin (HA) envelope protein of influenza viruses mediates essential viral functions, including receptor binding and membrane fusion, and is the major viral antigen for antibody neutralization. (asm.org)
  • Membrane fusion is the critical step for infectious cell penetration by enveloped viruses. (elifesciences.org)
  • Comparison of simulations with data from H3N2 and H1N1 viruses reveals three independent functional variables of HA-mediated membrane fusion closely linked to neutralization susceptibility. (elifesciences.org)
  • The mammalian influenza viruses, including the human ones, resemble the apathogenic avian strains in possessing also hemagglutinins of restricted cleavability and in causing usually local infection of the respiratory tract. (springer.com)
  • Molecular Docking of Human-Like Receptor to Hemagglutinins of Avian Influenza A Viruses[J].Acta Phys. (pku.edu.cn)
  • anti-viral drug discovery, influenza-virus hemagglutinin, ligand-protein interaction, STD-NMR spectroscopy, transfected cells Introduction Influenza viruses are important respiratory pathogens causing significant morbidity, mortality and considerable economic losses in the recurrent yearly epidemics and much more devastatingly in the sporadic pandemic spreads. (deepdyve.com)
  • We also compare the COVID-19 pathogenesis with that of severe outbreaks of "avian" influenza caused by the A/H5 and A/H7 highly pathogenic viruses and discuss the structural similarities between the SARS-CoV-2 S protein and hemagglutinins of those highly pathogenic strains. (bvsalud.org)
  • The viruses recognized are all in group 1 of Hemagglutinins. (bvsalud.org)
  • Here we focus on the hemagglutinins (HAs) of these viruses and assess their receptor binding phenotype in relation to previous HAs studied. (asm.org)
  • Understanding the molecular properties of H7N9 influenza viruses and the contribution of each viral protein to human disease are critical requirements for guiding public health responses to current and future outbreaks. (asm.org)
  • We compared the viral hemagglutinin, phosphoprotein, and fusion (F) and matrix (M) protein gene sequences with those of viruses from the 1988 and 2002 PDV epizootics. (qub.ac.uk)
  • Hyperfusogenic viruses with such mutations, unlike the wild-type MV, can induce cell-cell fusion even in SLAM- and nectin 4-negative cells and spread efficiently in human primary neurons and the brains of animal models. (elsevier.com)
  • Aims: To identify peptides that mimic (mimotopes) conformational and protective epitopes of RSV fusion protein and to assess their efficacy as immunogens and potential vaccines. (tudelft.nl)
  • Comparison of neuraminidases of paramyxoviruses with immunologically dissimilar hemagglutinins. (microbiologyresearch.org)
  • They bind viral ligands such as hemagglutinins and hemagglutinin neuraminidases, some bacterial ligands and cellular ligands related with tumour growth such as PCNA . (wikipedia.org)
  • HA is the primary antigen involved in the host immune response to viral infection. (asm.org)
  • The HA of influenza virus is a receptor-binding and fusion protein that is required to initiate infection. (pnas.org)
  • Dynamic viral-bacterial interactions in a porcine precision-cut lung slice co-infection model: swine influenza virus paves the way for Streptococcus suis infection in a two-step process. (tiho-hannover.de)
  • By monitoring B cell responses targeting conserved HA epitopes in mice, we previously demonstrated that influenza virus infection induces ectopic formation of lung GCs at the viral replication site, where cross-reactive B cells are selected at increased frequencies 12 . (nature.com)
  • Salinomycin Inhibits Influenza Virus Infection by Disrupting Endosomal Acidification and Viral Matrix Protein 2 Function. (amedeo.com)
  • Attenuation of influenza A virus disease severity by viral co-infection in a mouse model. (amedeo.com)
  • Of these proteases, some type II transmembrane serine proteases (TTSPs) family members such as human airway trypsin-like (HAT) protease, transmembrane protease, serine 2 (TMPRSS2), transmembrane protease, serine 4 (TMPRSS4), and mosaic serine protease large form (MSPL) play important roles in influenza viral infection. (hindawi.com)
  • Sion ML, Hatzitolios AI, Toulis EN, Mikoudi KD, Ziakas GN (2001) Toxic shock syndrome complicating influenza A infection: A two-case report with one case of bacteremia and endocarditis. (springer.com)
  • At optimal pH the HA conformational change was not rate-limiting for the fusion process. (biomedsearch.com)
  • However, at sub-optimal pH, the slow transition to the fusogenic conformational of HA resulted in slower kinetics and decreased extent of fusion. (biomedsearch.com)
  • Influenza hemagglutinin (HA) undergoes a conformational change that induces viral fusion with the cellular membrane. (nih.gov)
  • The acidic pH treated viral vaccine showed high susceptibility to proteolytic cleavage and low hemagglutination activity indicating conformational changes. (pubmedcentralcanada.ca)
  • 6. Huang Q, Sivaramakrishna RP, Ludwig K, Korte T, Bottcher C, Herrmann A. Early steps of the conformational change of influenza virus hemagglutinin to a fusion active state: stability and energetics of the hemagglutinin. (edu.pl)
  • Mair CM, Meyer T, Schneider K, Huang Q, Veit M, Herrmann A. A histidine residue of the influenza virus hemagglutinin controls the pH dependence of the conformational change mediating membrane fusion. (fu-berlin.de)
  • We compared the extent of positive selection acting on acute and persistent strains of measles virus (MV). Far stronger positive selection was found in the fusion (F) and haemagglutinin (H) genes from subacute sclerosing panencephalitis (SSPE) compared to acute MV cases. (ox.ac.uk)
  • The screen yielded 23 MAbs with diverse germ line origins that recognized hemagglutinins (HAs) derived from influenza strains of both the Yamagata and Victoria lineages of IBV. (asm.org)
  • Recent studies have shown that many virus strains isolated from SSPE patients possess substitutions in the extracellular domain of the fusion (F) protein which confer enhanced fusion activity. (elsevier.com)
  • Cell fusion assay indicated that TMPRSS2 and MSPL cell lines could cleave the HA protein of H5 and H9 subtypes. (hindawi.com)
  • 00:00:50.01 packages viral genomes, escapes from the infected cell, 00:00:54.22 survives transfer from one cell to another, and attaches, 00:00:59.01 penetrates, and initiates replication in the new host cell. (ibiology.org)
  • Germinal center (GC) B cells at viral replication sites acquire specificity to poorly immunogenic but conserved influenza hemagglutinin (HA) epitopes. (nature.com)
  • A distinct feature of this epitope is an occlusion in the naive trimeric HA structure that is exposed in the post-fusion HA structure to occur under low pH conditions during viral replication. (nature.com)
  • MicroRNA hsa-miR-324-5p Suppresses H5N1 Virus Replication by Targeting the Viral PB1 and Host CUEDC2. (amedeo.com)
  • The success of the evolution of RNA virus es arises from their capacity to utilize varying replication approaches and to adapt to a wide range of biological niches faced during viral spread in the host. (mediaatlas.si)
  • The process, termed "antibody-induced antigenic modulation," was further investigated by using monoclonal antibody to several viral polypeptides. (scripps.edu)
  • The abundance and structural conservation of this motif, even in the absence of sequence homology, suggests that it is critical for viral-cellular membrane fusion. (princeton.edu)
  • High-resolution structures are available for the HA precursor (HA0), the cleaved neutral pH conformation of HA, and the low pH conformation that the HA assumes when triggered by acidification of endosomes to mediate fusion of viral and cellular membrane during virus entry. (springer.com)
  • The HA protein on the virion surface is a trimer, in a pre-fusion state as HA0 and is then cleaved by cellular proteases to HA1 and HA2 3 . (nature.com)
  • Hemagglutinin (HA) of influenza virus mediates both receptor binding and membrane fusion [ 10 ]. (hindawi.com)
  • Universal epitopes of influenza virus hemagglutinins? (bvsalud.org)
  • Antibody breadth or cross-reactivity is achieved by two different pathways: germline-encoded cross-reactivity for variable viral epitopes or somatic evolution in germinal centers (GCs) for conserved viral epitopes 2 . (nature.com)
  • Protective cross-reactivity is also acquired by targeting conserved viral epitopes that are often immunosubdominant and poorly immunogenic. (nature.com)
  • Here, we describe characterization, immunogenicity, antigenicity, and protective immunity induced by low pH treated inactivated whole viral vaccine in comparison with the untreated vaccine. (pubmedcentralcanada.ca)
  • The transition of the S protein pre-fusion conformation to the post-fusion one on the surface of virions after their treatment with some reagents, such as ß-propiolactone, is essential, especially in relation to the vaccine production. (bvsalud.org)
  • Inaccuracies in prediction of circulating viral strain genotypes and the possibility of novel reassortants causing a pandemic outbreak necessitate the development of an anti-influenza vaccine with increased breadth of protection and potential for rapid production and deployment. (nature.com)
  • N-Glycosylation of Seasonal Influenza Vaccine Hemagglutinins: Implication for potency testing and immune processing. (amedeo.com)
  • a 16 amino acid sequence at the C-terminal end that is cleaved off by the viral protease (PR) after the virion has been released from the cell. (hubpages.com)
  • We have previously used single-virion measurements of fusion kinetics to study the molecular mechanism of influenza-virus envelope fusion. (elifesciences.org)
  • This finding provides a powerful rationale for testing the protective activity of these relatively conserved viral components in humans. (cdc.gov)
  • These structures, which represent the highest resolutions yet recorded for a complete ectodomain of a glycosylated viral surface antigen, along with the results of glycan microarray binding analysis, suggest that a hydrophobicity switch at residue 226 and elongation of receptor-binding sites were both critical for avian H2 HA to acquire human receptor specificity. (asm.org)
  • Wei Y, Feng K, Yao X, Cai H, Li J, Mirza AM, Iorio RM, Li J. Localization of a region in the fusion protein of avian metapneumovirus that modulates cell-cell fusion. (umassmed.edu)
  • 2000) Early alterations of the receptor-binding properties of H1, H2, and H3 avian influenza virus hemagglutinins after their introduction into mammals. (scirp.org)
  • Receptor binding and membrane fusion in virus entry: the influenza hemagglutinin. (scienceopen.com)
  • In this review we summarize recent findings on the molecular evolution of HCoV genomes, with special attention to recombination and adaptive events that generated new viral species and contributed to host shifts and to HCoV emergence. (cdc.gov)
  • During the budding process, the viral cargo is attached to the host cell once again via hemagglutinins, allowing the viral particle to form completely. (proteopedia.org)
  • preventing the viral particle from being released from the infected cell, thus limiting the severity and spread of viral infections . (proteopedia.org)
  • To prevent these viral infections an understanding of the host-virus response is critical, especially for the development of novel therapeutics. (usda.gov)
  • It will not work for viral infections (such as common cold, flu). (courtfield.tk)
  • Rapid and secure diagnosis of viral infections is a key factor for treatment of these diseases avoiding new spread. (mediaatlas.si)
  • Long lasting protection against viral infections is best achieved via vaccinations through live attenuated virus es (LAVs). (mediaatlas.si)
  • Highly immunogenic influenza hemagglutinins are urgently required to meet these pre-conditions. (biomedcentral.com)
  • The observed decreases were not due to preferential degradation of viral polypeptides as determined by pulse-chase experiments. (scripps.edu)
  • We produced trimeric H5 hemagglutinins in the endoplasmic reticulum of plant leaf cells. (biomedcentral.com)
  • They promote cell membrane fusion and thereby may function in the uptake of the virus by cells. (umassmed.edu)
  • Re-5, Re-6, and Re-9 efficiently infected and replicated within MDCK-TMPRSS2 and MDCK-MSPL cells and viral titer were comparable to the virus grown in MDCK cells with TPCK-trypsin. (hindawi.com)
  • Polyclonal antibody to measles virus can have profound effects on external (outer plasma membrane) as well as internal (cytoplasmic) viral polypeptides expressed in infected cells. (scripps.edu)
  • Also, low pH treated influenza viral antigen showed lower antigenicity compared to the untreated influenza viral antigen. (pubmedcentralcanada.ca)
  • Our results also showed some mutation position residing outside the previously reported antigenic site that may involve in an alteration of the viral antigenicity. (biomedcentral.com)
  • These structures have provided clues regarding the mechanisms by which proteolytic cleavage activates membrane fusion potential and how subsequent acidification drives the fusion process. (springer.com)
  • The Australia-Victoria (AV) isolate of Newcastle disease virus (NDV) induces fusion from within but not fusion from without. (umassmed.edu)
  • Individual roles of N-linked oligosaccharide chains in intracellular transport of the paramyxovirus SV5 fusion protein. (microbiologyresearch.org)
  • the metastable neutral-pH conformation found on virus, and the fusion pH-induced conformation. (scienceopen.com)
  • When the influenza virus infects a host cell, it attaches itself to the host via hemagglutinin interactions with host glycans, facilitating the fusion of host endosomal membrane with the viral membrane. (proteopedia.org)
  • The results suggest that fusion starts with the lateral assembly of activated HA into multimeric complexes surrounding future fusion sites. (mblwhoilibrary.org)
  • Structures of receptor complexes formed by hemagglutinins from the Asian influenza pandemic of 1957. (edu.pl)
  • Structural intermediates in influenza haemagglutinin-mediated fusion. (mblwhoilibrary.org)
  • Fusion pore formation in the haemagglutinin (HA)-mediated fusion is a culmination of a multistep process, which involves low-pH triggered refolding of HA and rearrangement of membrane lipid bilayers. (mblwhoilibrary.org)
  • Structure of influenza haemagglutinin at the pH of membrane fusion. (springer.com)
  • Secondarily, HA is responsible for the fusion of the viral envelope with the late endosomal membrane once exposed to low pH (5.0-5.5). (wikipedia.org)
  • Together they form a knob or knobbed spike on the surface of the virus and both are required for viral entry. (hubpages.com)
  • The final step in the entry process is the fusion of the membrane that surrounds the influenza virus with the membrane of the host cell. (elifesciences.org)
  • HA plays two key functions in viral entry. (wikipedia.org)
  • Henipavirus membrane fusion and viral entry. (umassmed.edu)
  • Unraveling a three-step spatiotemporal mechanism of triggering of receptor-induced Nipah virus fusion and cell entry. (umassmed.edu)
  • M2 proton channel maintains pH across the viral envelope during cell entry and viral maturation. (deepdyve.com)
  • These structures provide a framework for designing and interpreting the results of experiments on the activity of HA in receptor binding, the generation of emerging and reemerging epidemics, and membrane fusion during viral entry. (scienceopen.com)
  • N-glycans on Nipah virus fusion protein protect against neutralization but reduce membrane fusion and viral entry. (microbiologyresearch.org)
  • This supports the potential role of this protein in viral entry. (mediaatlas.si)
  • The general feasibility of this goal is supported by studies in animal models that show that immunologic activities directed against relatively invariant viral determinants can reduce illness and death. (cdc.gov)
  • Therefore, an ability to control how often hemagglutinins insert into the membrane could allow the virus to adapt to host immune responses. (elifesciences.org)
  • Influenza Antigen Engineering Focuses Immune Responses to a Subdominant but Broadly Protective Viral Epitope. (harvard.edu)
  • In this way regions less accessible to the protein, which usually are very near to the viral membrane and unavailable, were able to be used by the immune system. (bvsalud.org)
  • In the present study, we successfully produced a trimeric COE protein as a native structure by fusion with the C-terminal isoleucine zipper trimerization (GCN4pII) motif in Nicotiana benthamiana , with a high expression level shown via semi-quantified Western blots. (frontiersin.org)
  • The C-terminus of HA2, also known as the transmembrane domain, spans the viral membrane and anchors protein to the membrane. (wikipedia.org)