title: Deacylation of the transmembrane domains of Sindbis virus envelope glycoproteins E1 and E2 does not affect low-pH-induced viral membrane fusion activity.
abstract: The envelope glycoproteins E1 and E2 of Sindbis virus are palmitoylated at cysteine residues within their transmembrane domains (E1 at position 430, and E2 at positions 388 and 390). Here, we investigated the in vitro membrane fusion activity of Sindbis virus variants (derived from the Toto 1101 infectious clone), in which the E1 C430 and/or E2 C388/390 residues had been substituted for alanines. Both the E1 and E2 mutant viruses, as well as a triple mutant virus, fused with liposomes in a strictly low-pH-dependent manner, the fusion characteristics being indistinguishable from those of the parent Toto 1101 virus. These results demonstrate that acylation of the transmembrane domain of Sindbis virus E1 and E2 is not required for expression of viral membrane fusion activity.
authors.affiliation: Department of Medical Microbiology, University of Groningen, The Netherlands.
authors.forename: J M
authors.initials: JM
authors.lastname: Smit
authors.forename: R
authors.initials: R
authors.lastname: Bittman
authors.forename: J
authors.initials: J
authors.lastname: Wilschut
mesh_terms: D000215:Acylation; D000818:Animals; D002478:Cells, Cultured; D006224:Cricetinae; D006863:Hydrogen-Ion Concentration; D008081:Liposomes / Q000378:metabolism; D008561:Membrane Fusion / Q000502:physiology*; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000378:metabolism*; D008715:Methionine / Q000378:metabolism; D017434:Protein Structure, Tertiary; D011721:Pyrenes / Q000378:metabolism; D012845:Sindbis Virus / Q000502:physiology*; D013462:Sulfur Radioisotopes; D014357:Trypsin / Q000378:metabolism; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000378:metabolism*
chemical_list: D008081:Liposomes; D008562:Membrane Glycoproteins; D011721:Pyrenes; D013462:Sulfur Radioisotopes; D014759:Viral Envelope Proteins; C022012:glycoprotein E1, Sindbis virus; C064950:glycoprotein E2, Sindbis virus; C030984:pyrene; D008715:Methionine; D014357:Trypsin