Mutations in the stalk of the measles virus hemagglutinin protein decrease fusion but do not interfere with virus-specific interaction with the homologous fusion protein
UMass Chan Affiliations
Department of Molecular Genetics and MicrobiologyGraduate School of Biomedical Sciences
Document Type
Journal ArticlePublication Date
2007-07-13Keywords
Hela Cells; Hemagglutinins, Viral; Humans; Measles virus; *Mutation; Newcastle disease virus; Protein Binding; Protein Structure, Tertiary; Sequence Homology, Amino Acid; Viral Fusion Proteins; *Virus InternalizationLife Sciences
Medicine and Health Sciences
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The hemagglutinin (H) protein of measles virus (MV) mediates attachment to cellular receptors. The ectodomain of the H spike is thought to consist of a membrane-proximal stalk and terminal globular head, in which resides the receptor-binding activity. Like other paramyxovirus attachment proteins, MV H also plays a role in fusion promotion, which is mediated through an interaction with the viral fusion (F) protein. The stalk of the hemagglutinin-neuraminidase (HN) protein of several paramyxoviruses determines specificity for the homologous F protein. In addition, mutations in a conserved domain in the Newcastle disease virus (NDV) HN stalk result in a sharp decrease in fusion and an impaired ability to interact with NDV F in a cell surface coimmunoprecipitation (co-IP) assay. The region of MV H that determines specificity for the F protein has not been identified. Here, we have adapted the co-IP assay to detect the MV H-F complex at the surface of transfected HeLa cells. We have also identified mutations in a domain in the MV H stalk, similar to the one in the NDV HN stalk, that also drastically reduce fusion yet do not block complex formation with MV F. These results indicate that this domain in the MV H stalk is required for fusion but suggest either that mutation of it indirectly affects the H-dependent activation of F or that the MV H-F interaction is mediated by more than one domain in H. This points to an apparent difference in the way the MV and NDV glycoproteins interact to regulate fusion.Source
J Virol. 2007 Sep;81(18):9900-10. Epub 2007 Jul 11. Link to article on publisher's siteDOI
10.1128/JVI.00909-07Permanent Link to this Item
http://hdl.handle.net/20.500.14038/33575PubMed ID
17626104Related Resources
Link to article in PubMedae974a485f413a2113503eed53cd6c53
10.1128/JVI.00909-07
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