scholarly journals Structural and functional analyses reveal promiscuous and species specific use of ephrin receptors by Cedar virus

2019 ◽  
Vol 116 (41) ◽  
pp. 20707-20715 ◽  
Author(s):  
Eric D. Laing ◽  
Chanakha K. Navaratnarajah ◽  
Sofia Cheliout Da Silva ◽  
Stephanie R. Petzing ◽  
Yan Xu ◽  
...  
Keyword(s):  
Receptor Binding ◽  
Contact Region ◽  
Nipah Virus ◽  
Hendra Virus ◽  
Receptor Binding Site ◽  
Sequence Identity ◽  
Ephrin Receptors ◽  
Species Specific ◽  
Functional Analyses ◽  
Entry Receptor

Cedar virus (CedV) is a bat-borne henipavirus related to Nipah virus (NiV) and Hendra virus (HeV), zoonotic agents of fatal human disease. CedV receptor-binding protein (G) shares only ∼30% sequence identity with those of NiV and HeV, although they can all use ephrin-B2 as an entry receptor. We demonstrate that CedV also enters cells through additional B- and A-class ephrins (ephrin-B1, ephrin-A2, and ephrin-A5) and report the crystal structure of the CedV G ectodomain alone and in complex with ephrin-B1 or ephrin-B2. The CedV G receptor-binding site is structurally distinct from other henipaviruses, underlying its capability to accommodate additional ephrin receptors. We also show that CedV can enter cells through mouse ephrin-A1 but not human ephrin-A1, which differ by 1 residue in the key contact region. This is evidence of species specific ephrin receptor usage by a henipavirus, and implicates additional ephrin receptors in potential zoonotic transmission.

scholarly journals Evidence of a Potential Receptor-Binding Site on the Nipah Virus G Protein (NiV-G): Identification of Globular Head Residues with a Role in Fusion Promotion and Their Localization on an NiV-G Structural Model

2006 ◽  
Vol 80 (15) ◽  
pp. 7546-7554 ◽  
Author(s):  
Vanessa Guillaume ◽  
Hamide Aslan ◽  
Michelle Ainouze ◽  
Mathilde Guerbois ◽  
T. Fabian Wild ◽  
...  
Keyword(s):  
Binding Site ◽  
G Protein ◽  
Receptor Binding ◽  
Measles Virus ◽  
Structural Model ◽  
Nipah Virus ◽  
Hendra Virus ◽  
Receptor Binding Site ◽  
Globular Head

ABSTRACT As a preliminary to the localization of the receptor-binding site(s) on the Nipah virus (NiV) glycoprotein (NiV-G), we have undertaken the identification of NiV-G residues that play a role in fusion promotion. To achieve this, we have used two strategies. First, as NiV and Hendra virus (HeV) share a common receptor and their cellular tropism is similar, we hypothesized that residues functioning in receptor attachment could be conserved between their respective G proteins. Our initial strategy was to target charged residues (which can be expected to be at the surface of the protein) conserved between the NiV-G and HeV-G globular heads. Second, we generated NiV variants that escaped neutralization by anti-NiV-G monoclonal antibodies (MAbs) that neutralize NiV both in vitro and in vivo, likely by blocking receptor attachment. The sequencing of such “escape mutants” identified NiV-G residues present in the epitopes to which the neutralizing MAbs are directed. Residues identified via these two strategies whose mutation had an effect on fusion promotion were localized on a new structural model for the NiV-G protein. Our results suggest that seven NiV-G residues, including one (E533) that was identified using both strategies, form a contiguous site on the top of the globular head that is implicated in ephrinB2 binding. This site commences near the shallow depression in the center of the top surface of the globular head and extends to the rim of the barrel-like structure on the top loops of β-sheet 5. The topology of this site is strikingly similar to that proposed to form the SLAM receptor site on another paramyxovirus attachment protein, that of the measles virus hemagglutinin.

scholarly journals Identification of Hendra Virus G Glycoprotein Residues That Are Critical for Receptor Binding

2007 ◽  
Vol 81 (11) ◽  
pp. 5893-5901 ◽  
Author(s):  
Kimberly A. Bishop ◽  
Tzanko S. Stantchev ◽  
Andrew C. Hickey ◽  
Dimple Khetawat ◽  
Katharine N. Bossart ◽  
...  
Keyword(s):  
Receptor Binding ◽  
Measles Virus ◽  
Mammalian Species ◽  
Hendra Virus ◽  
Host Cells ◽  
Single Amino Acid ◽  
Receptor Interaction ◽  
Alanine Scanning Mutagenesis ◽  
Receptor Binding Site ◽  
Protein Receptor

ABSTRACT Hendra virus (HeV) is an emerging paramyxovirus capable of infecting and causing disease in a variety of mammalian species, including humans. The virus infects its host cells through the coordinated functions of its fusion (F) and attachment (G) glycoproteins, the latter of which is responsible for binding the virus receptors ephrinB2 and ephrinB3. In order to identify the receptor binding site, a panel of G glycoprotein constructs containing mutations was generated using an alanine-scanning mutagenesis strategy. Based on a predicted G structure, charged amino acids residing in regions that could be homologous to those in the measles virus H attachment glycoprotein known to be involved in its protein receptor interaction were targeted. Using a coprecipitation-based assay, seven single-amino-acid substitutions in HeV G were identified as having significantly impaired binding to both the ephrinB2 and ephrinB3 viral receptors: D257A, D260A, G439A, K443A, G449A, K465A, and D468A. The impairment of receptor interaction conferred a concomitant diminution in their abilities to promote membrane fusion when coexpressed with F. The G glycoprotein mutants were also recognized by three or more conformation-dependent monoclonal antibodies of a panel of five, were expressed on the cell surface, and retained their abilities to bind and coprecipitate F. Interestingly, some of these mutant G glycoproteins coprecipitated with F more efficiently than wild-type G. Taken together, these data provide strong biochemical and functional evidence that some of these residues could be part of a conformation-dependent, discontinuous, and overlapping ephrinB2 and -B3 binding domain within the HeV G glycoprotein.

scholarly journals A Second Receptor Binding Site on Human Parainfluenza Virus Type 3 Hemagglutinin-Neuraminidase Contributes to Activation of the FusionMechanism

2007 ◽  
Vol 81 (7) ◽  
pp. 3216-3228 ◽  
Author(s):  
Matteo Porotto ◽  
Micaela Fornabaio ◽  
Glen E. Kellogg ◽  
Anne Moscona
Keyword(s):  
Binding Site ◽  
Receptor Binding ◽  
Cell Interaction ◽  
Binding Activity ◽  
Viral Fusion ◽  
Receptor Binding Site ◽  
Computational Data ◽  
Human Parainfluenza Virus ◽  
Type 3 ◽  
Entry Receptor

ABSTRACT The hemagglutinin-neuraminidase (HN) protein of paramyxoviruses carries out three discrete activities that each affect the ability of HN to promote viral fusion and entry: receptor binding, receptor cleaving (neuraminidase), and triggering of the fusion protein. The interrelationship between the receptor binding and fusion-triggering functions of HN has not been clear. For human parainfluenza type 3 (HPIV3), one bifunctional site on HN can carry out both receptor binding and neuraminidase activities, and this site's receptor binding can be inhibited by the small receptor analog zanamivir. We now report experimental evidence, complemented by computational data, for a second receptor binding site near the HPIV3 HN dimer interface. This second binding site can mediate receptor binding even in the presence of zanamivir, and it differs from the second receptor binding site of the paramyxovirus Newcastle disease virus in its function and its relationship to the primary binding site. This second binding site of HPIV3 HN is involved in triggering F. We suggest that the two receptor binding sites on HPIV3 HN each contribute in distinct ways to virus-cell interaction; one is the multifunctional site that contains both binding and neuraminidase activities, and the other contains binding activity and also is involved in fusion promotion.

scholarly journals Dimeric Architecture of the Hendra Virus Attachment Glycoprotein: Evidence for a Conserved Mode of Assembly

2010 ◽  
Vol 84 (12) ◽  
pp. 6208-6217 ◽  
Author(s):  
Thomas A. Bowden ◽  
Max Crispin ◽  
David J. Harvey ◽  
E. Yvonne Jones ◽  
David I. Stuart
Keyword(s):  
Receptor Binding ◽  
Rna Virus ◽  
Nipah Virus ◽  
Hendra Virus ◽  
Striking Similarity ◽  
Dimer Interface ◽  
Virus Attachment ◽  
Positional Analysis ◽  
Protein Receptor ◽  
Glycan Receptors

ABSTRACT Hendra virus is a negative-sense single-stranded RNA virus within the Paramyxoviridae family which, together with Nipah virus, forms the Henipavirus genus. Infection with bat-borne Hendra virus leads to a disease with high mortality rates in humans. We determined the crystal structure of the unliganded six-bladed β-propeller domain and compared it to the previously reported structure of Hendra virus attachment glycoprotein (HeV-G) in complex with its cellular receptor, ephrin-B2. As observed for the related unliganded Nipah virus structure, there is plasticity in the Glu579-Pro590 and Lys236-Ala245 ephrin-binding loops prior to receptor engagement. These data reveal that henipaviral attachment glycoproteins undergo common structural transitions upon receptor binding and further define the structural template for antihenipaviral drug design. Our analysis also provides experimental evidence for a dimeric arrangement of HeV-G that exhibits striking similarity to those observed in crystal structures of related paramyxovirus receptor-binding glycoproteins. The biological relevance of this dimer is further supported by the positional analysis of glycosylation sites from across the paramyxoviruses. In HeV-G, the sites lie away from the putative dimer interface and remain accessible to α-mannosidase processing on oligomerization. We therefore propose that the overall mode of dimer assembly is conserved for all paramyxoviruses; however, while the geometry of dimerization is rather closely similar for those viruses that bind flexible glycan receptors, significant (up to 60°) and different reconfigurations of the subunit packing (associated with a significant decrease in the size of the dimer interface) have accompanied the independent switching to high-affinity protein receptor binding in Hendra and measles viruses.

scholarly journals Functional Analysis of the Fusion and Attachment Glycoproteins of Mojiang Henipavirus

Viruses ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 517
Author(s):  
Sofia Cheliout Da Silva ◽  
Lianying Yan ◽  
Ha V. Dang ◽  
Kai Xu ◽  
Jonathan H. Epstein ◽  
...  
Keyword(s):  
Functional Analysis ◽  
Cell Fusion ◽  
Sequence Data ◽  
Nipah Virus ◽  
Hendra Virus ◽  
Soluble Form ◽  
Fusion Activity ◽  
Low Levels ◽  
Entry Receptor ◽  
Functional Defects

Mojiang virus (MojV) is the first henipavirus identified in a rodent and known only by sequence data, whereas all other henipaviruses have been isolated from bats (Hendra virus, Nipah virus, Cedar virus) or discovered by sequence data from material of bat origin (Ghana virus). Ephrin-B2 and -B3 are entry receptors for Hendra and Nipah viruses, but Cedar virus can utilize human ephrin-B1, -B2, -A2 and -A5 and mouse ephrin-A1. However, the entry receptor for MojV remains unknown, and its species tropism is not well characterized. Here, we utilized recombinant full-length and soluble forms of the MojV fusion (F) and attachment (G) glycoproteins in membrane fusion and receptor tropism studies. MojV F and G were functionally competent and mediated cell–cell fusion in primate and rattine cells, albeit with low levels and slow fusion kinetics. Although a relative instability of the pre-fusion conformation of a soluble form of MojV F was observed, MojV F displayed significantly greater fusion activity when heterotypically paired with Ghana virus G. An exhaustive investigation of A- and B-class ephrins indicated that none serve as a primary receptor for MojV. The MojV cell fusion phenotype is therefore likely the result of receptor restriction rather than functional defects in recombinant MojV F and G glycoproteins.

scholarly journals Potent sialic acid inhibitors that target influenza A virus hemagglutinin

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yu-Jen Chang ◽  
Cheng-Yun Yeh ◽  
Ju-Chien Cheng ◽  
Yu-Qi Huang ◽  
Kai-Cheng Hsu ◽  
...  
Keyword(s):  
Sialic Acid ◽  
Antiviral Activity ◽  
Binding Site ◽  
Influenza A Virus ◽  
Receptor Binding ◽  
Influenza A ◽  
The United States ◽  
Ligand Complex ◽  
Receptor Binding Site ◽  
Computational Strategy

AbstractEradicating influenza A virus (IAV) is difficult, due to its genetic drift and reassortment ability. As the infectious cycle is initiated by the influenza glycoprotein, hemagglutinin (HA), which mediates the binding of virions to terminal sialic acids moieties, HA is a tempting target of anti-influenza inhibitors. However, the complexity of the HA structure has prevented delineation of the structural characterization of the HA protein–ligand complex. Our computational strategy efficiently analyzed > 200,000 records of compounds held in the United States National Cancer Institute (NCI) database and identified potential HA inhibitors, by modeling the sialic acid (SA) receptor binding site (RBS) for the HA structure. Our modeling revealed that compound NSC85561 showed significant antiviral activity against the IAV H1N1 strain with EC50 values ranging from 2.31 to 2.53 µM and negligible cytotoxicity (CC50 > 700 µM). Using the NSC85561 compound as the template to generate 12 derivatives, robust bioassay results revealed the strongest antiviral efficacies with NSC47715 and NSC7223. Virtual screening clearly identified three SA receptor binding site inhibitors that were successfully validated in experimental data. Thus, our computational strategy has identified SA receptor binding site inhibitors against HA that show IAV-associated antiviral activity.

Sign in / Sign up

Export Citation Format

Share Document