title: Hemagglutinin of influenza virus partitions into the nonraft domain of model membranes.
abstract: The HA of influenza virus is a paradigm for a transmembrane protein thought to be associated with membrane-rafts, liquid-ordered like nanodomains of the plasma membrane enriched in cholesterol, glycosphingolipids, and saturated phospholipids. Due to their submicron size in cells, rafts can not be visualized directly and raft-association of HA was hitherto analyzed by indirect methods. In this study, we have used GUVs and GPMVs, showing liquid disordered and liquid ordered domains, to directly visualize partition of HA by fluorescence microscopy. We show that HA is exclusively (GUVs) or predominantly (GPMVs) present in the liquid disordered domain, regardless of whether authentic HA or domains containing its raft targeting signals were reconstituted into model membranes. The preferential partition of HA into ld domains and the difference between lo partition in GUV and GPMV are discussed with respect to differences in packaging of lipids in membranes of model systems and living cells suggesting that physical properties of lipid domains in biological membranes are tightly regulated by protein-lipid interactions.
authors.affiliation: Department of Biology, Molecular Biophysics, Humboldt University Berlin, Berlin, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Nikolaus
authors.forename: Silvia
authors.initials: S
authors.lastname: Scolari
authors.forename: Elisa
authors.initials: E
authors.lastname: Bayraktarov
authors.forename: Nadine
authors.initials: N
authors.lastname: Jungnick
authors.forename: Stephanie
authors.initials: S
authors.lastname: Engel
authors.forename: Anna
authors.initials: A
authors.lastname: Pia Plazzo
authors.forename: Martin
authors.initials: M
authors.lastname: Stöckl
authors.forename: Rudolf
authors.initials: R
authors.lastname: Volkmer
authors.forename: Michael
authors.initials: M
authors.lastname: Veit
authors.forename: Andreas
authors.initials: A
authors.lastname: Herrmann
mesh_terms: D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000378:metabolism*; D008055:Lipids / Q000737:chemistry; D021962:Membrane Microdomains / Q000378:metabolism*; D008567:Membranes, Artificial; D008954:Models, Biological; D010455:Peptides / Q000737:chemistry; D017434:Protein Structure, Tertiary; D013050:Spectrometry, Fluorescence; D053835:Unilamellar Liposomes / Q000378:metabolism
chemical_list: D019267:Hemagglutinin Glycoproteins, Influenza Virus; D008055:Lipids; D008567:Membranes, Artificial; D010455:Peptides; D053835:Unilamellar Liposomes