title: The measles virus hemagglutinin β-propeller head β4-β5 hydrophobic groove governs functional interactions with nectin-4 and CD46 but not those with the signaling lymphocytic activation molecule.
abstract: Wild-type measles virus (MV) strains use the signaling lymphocytic activation molecule (SLAM; CD150) and the adherens junction protein nectin-4 (poliovirus receptor-like 4 [PVRL4]) as receptors. Vaccine MV strains have adapted to use ubiquitous membrane cofactor protein (MCP; CD46) in addition. Recently solved cocrystal structures of the MV attachment protein (hemagglutinin [H]) with each receptor indicate that all three bind close to a hydrophobic groove located between blades 4 and 5 (β4-β5 groove) of the H protein β-propeller head. We used this structural information to focus our analysis of the functional footprints of the three receptors on vaccine MV H. We mutagenized this protein and tested the ability of individual mutants to support cell fusion through each receptor. The results highlighted a strong overlap between the functional footprints of nectin-4 and CD46 but not those of SLAM. A soluble form of nectin-4 abolished vaccine MV entry in nectin-4- and CD46-expressing cells but only reduced entry through SLAM. Analyses of the binding kinetics of an H mutant with the three receptors revealed that a single substitution in the β4-β5 groove drastically reduced nectin-4 and CD46 binding while minimally altering SLAM binding. We also generated recombinant viruses and analyzed their infections in cells expressing individual receptors. Introduction of a single substitution into the hydrophobic pocket affected entry through both nectin-4 and CD46 but not through SLAM. Thus, while nectin-4 and CD46 interact functionally with the H protein β4-β5 hydrophobic groove, SLAM merely covers it. This has implications for vaccine and antiviral strategies.
authors.affiliation: Department of Molecular Medicine, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Mateo
authors.forename: Chanakha K
authors.initials: CK
authors.lastname: Navaratnarajah
authors.forename: Sabriya
authors.initials: S
authors.lastname: Syed
authors.forename: Roberto
authors.initials: R
authors.lastname: Cattaneo
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D002522:Chlorocebus aethiops; D004252:DNA Mutational Analysis; D054884:Host-Pathogen Interactions; D008459:Measles virus / Q000502:physiology*; D051916:Membrane Cofactor Protein / Q000378:metabolism*; D011485:Protein Binding; D025941:Protein Interaction Mapping; D011956:Receptors, Cell Surface / Q000378:metabolism*; D011991:Receptors, Virus / Q000378:metabolism; D000071177:Signaling Lymphocytic Activation Molecule Family Member 1; D014709:Vero Cells; D014764:Viral Proteins / Q000378:metabolism*; D053586:Virus Internalization; D000075983:Nectins
chemical_list: D015703:Antigens, CD; D015815:Cell Adhesion Molecules; D051916:Membrane Cofactor Protein; D011956:Receptors, Cell Surface; D011991:Receptors, Virus; D000071177:Signaling Lymphocytic Activation Molecule Family Member 1; D014764:Viral Proteins; C497857:CD46 protein, human; C000604059:SLAMF1 protein, human; C442228:NECTIN4 protein, human; D000075983:Nectins