Department of Molecular Genetics and Microbiology
Animals; Cell Line; Chick Embryo; HN Protein; Immunoprecipitation; Membrane Fusion; Newcastle disease virus; Receptors, Cell Surface; Transfection; Viral Fusion Proteins
Life Sciences | Medicine and Health Sciences
Receptor binding of paramyxovirus attachment proteins and the interactions between attachment and fusion (F) proteins are thought to be central to activation of the F protein activity; however, mechanisms involved are unclear. To explore the relationships between Newcastle disease virus (NDV) HN and F protein interactions and HN protein attachment to sialic acid receptors, HN and F protein-containing complexes were detected and quantified by reciprocal coimmunoprecipitation from extracts of transfected avian cells. To inhibit HN protein receptor binding, cells transfected with HN and F protein cDNAs were incubated with neuraminidase from the start of transfection. Under these conditions, no fusion was observed, but amounts of HN and F protein complexes increased twofold over amounts detected in extracts of untreated cells. Stimulation of attachment by incubation of untransfected target cells with neuraminidase-treated HN and F protein-expressing cells resulted in a twofold decrease in amounts of HN and F protein complexes. In contrast, high levels of complexes containing HN protein and an uncleaved F protein (F-K115Q) were detected, and those levels were unaffected by neuraminidase treatment of cell monolayers or by incubation with target cells. These results suggest that HN and F proteins reside in a complex in the absence of receptor binding. Furthermore, the results show that not only receptor binding but also F protein cleavage are necessary for disassociation of the HN and F protein-containing complexes.
DOI of Published Version
J Virol. 2006 Mar;80(6):2894-903. Link to article on publisher's site
Journal of virology
McGinnes, Lori and Morrison, Trudy G., "Inhibition of receptor binding stabilizes Newcastle disease virus HN and F protein-containing complexes" (2006). Open Access Articles. 1515.