title: Functional expression and membrane fusion tropism of the envelope glycoproteins of Hendra virus.
abstract: Hendra virus (HeV) is an emerging paramyxovirus first isolated from cases of severe respiratory disease that fatally affected both horses and humans. Understanding the mechanisms of host cell infection and cross-species transmission is an important step in addressing the risk posed by such emerging pathogens. We have initiated studies to characterize the biological properties of the HeV envelope glycoproteins. Recombinant vaccinia viruses encoding the HeV F and G open reading frames were generated and glycoprotein expression was verified by metabolic labeling and detection using specific antisera. Glycoprotein function and cellular tropism were examined with a quantitative assay for HeV-mediated membrane fusion. Fusion specificity was verified through specific inhibition by anti-HeV antiserum and a peptide corresponding to one of the alpha-helical heptad repeats of F. HeV requires both F and G to mediate fusion. Permissive target cells have been identified, including cell lines derived from cat, bat, horse, human, monkey, mouse, and rabbit. Fusion negative cell types have also been identified. Protease treatments of the target cells abolished fusion activity, suggesting that the virus is employing a cell-surface protein as its receptor.
authors.affiliation: Department of Microbiology, Uniformed Services University, Bethesda, Maryland 20814, USA.
authors.forename: K N
authors.initials: KN
authors.lastname: Bossart
authors.forename: L F
authors.initials: LF
authors.lastname: Wang
authors.forename: B T
authors.initials: BT
authors.lastname: Eaton
authors.forename: C C
authors.initials: CC
authors.lastname: Broder
mesh_terms: D016475:3T3 Cells; D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D019286:Endopeptidase K; D015726:Giant Cells; D006367:HeLa Cells; D006801:Humans; D008561:Membrane Fusion / Q000502:physiology*; D008562:Membrane Glycoproteins / Q000096:biosynthesis / Q000378:metabolism / Q000502:physiology*; D051379:Mice; D008969:Molecular Sequence Data; D018098:Paramyxovirinae / Q000378:metabolism / Q000502:physiology*; D014357:Trypsin; D014759:Viral Envelope Proteins / Q000096:biosynthesis / Q000502:physiology*; D014760:Viral Fusion Proteins / Q000096:biosynthesis / Q000502:physiology*
chemical_list: D008562:Membrane Glycoproteins; D014759:Viral Envelope Proteins; D014760:Viral Fusion Proteins; D014357:Trypsin; D019286:Endopeptidase K