Epitopes described in "Identification of Hendra virus G glycoprotein residues that are critical for receptor binding."

Article Authors:Kimberly A Bishop; Tzanko S Stantchev; Andrew C Hickey; Dimple Khetawat; Katharine N Bossart; Valery Krasnoperov; Parkash Gill; Yan Ru Feng; Lemin Wang; Bryan T Eaton; Lin-Fa Wang; Christopher C Broder
Article Title:Identification of Hendra virus G glycoprotein residues that are critical for receptor binding.
Reference Detail
Reference ID:1004952
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.
Affiliations:Department of Microbiology and Immunology, Uniformed Services University, Bethesda, MD 20814, USA.
Reference Type:Literature
PubMed ID:17376907
Journal:J Virol
Journal Volume:81
Article Pages:5893-901
Journal ISSN:1098-5514
Article Chemical List:Amino Acids;Ephrin-B2;Ephrin-B3;Receptors, Virus;Viral Envelope Proteins;attachment protein G
Article MeSH List:Amino Acid Substitution(genetics); Amino Acids(genetics; metabolism); Binding Sites(genetics); Cell Line; Ephrin-B2(metabolism); Ephrin-B3(metabolism); HeLa Cells; Hendra Virus(chemistry; genetics; metabolism); Humans; Predictive Value of Tests; Protein Binding; Protein Conformation; Receptors, Virus(metabolism); Viral Envelope Proteins(chemistry; genetics; metabolism)
Curation Last Updated:2015-06-05 00:54:40