title: Acylation and cholesterol binding are not required for targeting of influenza A virus M2 protein to the hemagglutinin-defined budozone.
abstract: Influenza virus assembles in the budozone, a cholesterol-/sphingolipid-enriched ("raft") domain at the apical plasma membrane, organized by hemagglutinin (HA). The viral protein M2 localizes to the budozone edge for virus particle scission. This was proposed to depend on acylation and cholesterol binding. We show that M2-GFP without these motifs is still transported apically in polarized cells. Employing FRET, we determined that clustering between HA and M2 is reduced upon disruption of HA's raft-association features (acylation, transmembranous VIL motif), but remains unchanged with M2 lacking acylation and/or cholesterol-binding sites. The motifs are thus irrelevant for M2 targeting in cells.
authors.affiliation: Freie Universität Berlin, Fachbereich Veterinärmedizin, Institut für Virologie, Zentrum für Infektionsmedizin - Robert-von-Ostertag-Haus, Robert-von-Ostertag-Straße 7-13, 14163 Berlin, Germany.
authors.forename: Bastian
authors.initials: B
authors.lastname: Thaa
authors.affiliation: Freie Universität Berlin, Fachbereich Veterinärmedizin, Institut für Virologie, Zentrum für Infektionsmedizin - Robert-von-Ostertag-Haus, Robert-von-Ostertag-Straße 7-13, 14163 Berlin, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Siche
authors.affiliation: Humboldt-Universität zu Berlin, Institute of Biology, Molecular Biophysics, Invalidenstraße 42, 10115 Berlin, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Herrmann
authors.affiliation: Freie Universität Berlin, Fachbereich Veterinärmedizin, Institut für Virologie, Zentrum für Infektionsmedizin - Robert-von-Ostertag-Haus, Robert-von-Ostertag-Straße 7-13, 14163 Berlin, Germany. Electronic address: mveit@zedat.fu-berlin.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Veit
mesh_terms: D000215:Acylation; D000818:Animals; D016466:CHO Cells; D016764:Cell Polarity; D002784:Cholesterol / Q000378:metabolism*; D006224:Cricetinae; D003412:Cricetulus; D004285:Dogs; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000378:metabolism; D009980:Influenza A virus / Q000502:physiology*; D061985:Madin Darby Canine Kidney Cells; D021962:Membrane Microdomains / Q000378:metabolism / Q000821:virology*; D011485:Protein Binding; D011499:Protein Processing, Post-Translational; D021381:Protein Transport; D014763:Viral Matrix Proteins / Q000378:metabolism*; D019065:Virus Assembly; D000086082:Viroporin Proteins
chemical_list: D002784:Cholesterol; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D014763:Viral Matrix Proteins; C488937:M2 protein, Influenza A virus; D000086082:Viroporin Proteins
keywords: Apical transport; Hemagglutinin; Influenza virus; M2; Palmitoylation; Raft localization