title: Identification of phosphorylated residues on varicella-zoster virus immediate-early protein ORF63.
abstract: Efficient replication of varicella-zoster virus (VZV) in cell culture requires expression of protein encoded by VZV open reading frame 63 (ORF63p). Two-dimensional gel analysis demonstrates that ORF63p is extensively modified. Mass spectroscopy analysis of ORF63p isolated from transiently transfected HEK 293 and stably transfected MeWo cells identified 10 phosphorylated residues. In VZV-infected MeWo cells, only six phosphorylated residues were detected. This report identifies phosphorylation of two previously uncharacterized residues (Ser5 and Ser31) in ORF63p extracted from cells infected with VZV or transfected with an ORF63p expression plasmid. Computational analysis of ORF63p for known kinase substrates did not identify Ser5 or Ser31 as candidate phosphorylation sites, suggesting that either atypical recognition sequences or novel cellular kinases are involved in ORF63p post-translational modification.
authors.affiliation: Department of Neurology, University of Colorado Denver School of Medicine, Denver, USA.
authors.forename: Niklaus H
authors.initials: NH
authors.lastname: Mueller
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Walters
authors.forename: Roland A
authors.initials: RA
authors.lastname: Marcus
authors.forename: Laurie L
authors.initials: LL
authors.lastname: Graf
authors.forename: Jessica
authors.initials: J
authors.lastname: Prenni
authors.forename: Don
authors.initials: D
authors.lastname: Gilden
authors.forename: Saul J
authors.initials: SJ
authors.lastname: Silverstein
authors.forename: Randall J
authors.initials: RJ
authors.lastname: Cohrs
mesh_terms: D000595:Amino Acid Sequence; D002460:Cell Line; D015180:Electrophoresis, Gel, Two-Dimensional; D014645:Herpesvirus 3, Human / Q000502:physiology*; D006801:Humans; D017874:Immediate-Early Proteins / Q000378:metabolism*; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D014759:Viral Envelope Proteins / Q000378:metabolism*; D014779:Virus Replication
chemical_list: D017874:Immediate-Early Proteins; D014759:Viral Envelope Proteins; C074551:immediate early protein 63, Human herpesvirus 3