title: Involvement of viral glycoprotein gC-1 in expression of the selectin ligand sialyl-Lewis X induced after infection with herpes simplex virus type 1.
abstract: Several herpesviruses induce expression of the selectin receptor sialyl-Lewis X (sLe(x) ) by activating transcription of one or more of silent host FUT genes, each one encoding a fucosyltransferase that catalyses the rate-limiting step of sLe(x) synthesis. The aim here was to identify the identity of the glycoconjugate associated with sLe(x) glycoepitope in herpes simplex virus type 1 (HSV-1) infected human diploid fibroblasts, using immunofluorescence confocal microscopy. Cells infected with all tested HSV-1 strains analysed demonstrated bright sLe(x) fluorescence, except for two mutant viruses that were unable to induce proper expression of viral glycoprotein gC-1: One gC-1 null mutant and another mutant expressing gC-1 devoid of its major O-glycan-containing region (aa 33-116). The sLe(x) reactivity of HSV-1 infected cells was abolished by mild alkali treatment. Altogether the results indicated that the detectable sLe(x) was associated with O-linked glycans, situated in the mucin region of gC-1. No evidence for sLe(x) (i) in other HSV-1 glycoproteins with mucin domains such as gI-1 or (ii) in host cell glycoproteins/glycolipids was found. Thus, the mucin domain of HSV-1 gC-1 may support expression of selectin ligands such as sLe(x) and other larger O-linked glycans in cell types lacking endogenous mucin domain-containing glycoproteins, optimized for O-glycan expression, provided that the adequate host glycosyltransferase genes are activated.
authors.affiliation: Department of Virology, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden.
authors.forename: Rickard
authors.initials: R
authors.lastname: Nordén
authors.forename: Kristina
authors.initials: K
authors.lastname: Nyström
authors.forename: Beata
authors.initials: B
authors.lastname: Adamiak
authors.forename: Adnan
authors.initials: A
authors.lastname: Halim
authors.forename: Jonas
authors.initials: J
authors.lastname: Nilsson
authors.forename: Göran
authors.initials: G
authors.lastname: Larson
authors.forename: Edward
authors.initials: E
authors.lastname: Trybala
authors.forename: Sigvard
authors.initials: S
authors.lastname: Olofsson
mesh_terms: D005347:Fibroblasts / Q000821:virology; D005647:Fucosyltransferases / Q000502:physiology; D006031:Glycosylation; D018259:Herpesvirus 1, Human / Q000502:physiology*; D006801:Humans; D016256:Lewis X Antigen / Q000096:biosynthesis*; D008024:Ligands; D009077:Mucins / Q000502:physiology; D000080506:Sialyl Lewis X Antigen; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000502:physiology*
chemical_list: D016256:Lewis X Antigen; D008024:Ligands; D009077:Mucins; D000080506:Sialyl Lewis X Antigen; D014759:Viral Envelope Proteins; C038535:glycoprotein gC, herpes simplex virus type 1; D005647:Fucosyltransferases; C019818:3-galactosyl-N-acetylglucosaminide 4-alpha-L-fucosyltransferase