title: Mimicking influenza virus fusion using supported lipid bilayers.
abstract: Influenza virus infection is a serious public health problem in the world, and understanding the molecular mechanisms involved in viral replication is crucial. In this paper, we used a minimalist approach based on a lipid bilayer supported on mica, which we imaged by atomic force microscopy (AFM) in a physiological buffer, to analyze the different steps of influenza fusion, from the interaction of intact viruses with the supported bilayer to their complete fusion. Our results show that sialic acid recognition and priming upon acidification are sufficient for a complete fusion with the host cell membrane. After fusion, a flat and continuous membrane was observed. Because of the fragility of the viral membrane that was removed by the tip, most probably due to the disorganization of the matrix layer at acidic pH, fine structural details of ribonucleoproteins (RNP) were obtained. In addition, AFM topography of intact virus in interaction with the supported lipid bilayer confirms that hemeagglutinin and neuraminidase can form isolated clusters within the viral membrane.
authors.affiliation: Institut National de la Santé et de la Recherche Médicale, Unité 1054, 34090 Montpellier, France.
authors.forename: Cédric
authors.initials: C
authors.lastname: Godefroy
authors.forename: Selma
authors.initials: S
authors.lastname: Dahmane
authors.forename: Patrice
authors.initials: P
authors.lastname: Dosset
authors.forename: Olivier
authors.initials: O
authors.lastname: Adam
authors.forename: Marie-Claire
authors.initials: MC
authors.lastname: Nicolai
authors.forename: Frédéric
authors.initials: F
authors.lastname: Ronzon
authors.forename: Pierre-Emmanuel
authors.initials: PE
authors.lastname: Milhiet
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D053122:Influenza A Virus, H3N2 Subtype / Q000737:chemistry*; D008051:Lipid Bilayers / Q000737:chemistry*; D008561:Membrane Fusion; D018625:Microscopy, Atomic Force; D012261:Ribonucleoproteins / Q000737:chemistry; D013499:Surface Properties; D053586:Virus Internalization
chemical_list: D000538:Aluminum Silicates; D008051:Lipid Bilayers; D012261:Ribonucleoproteins; C011934:mica