Varicella-zoster virus open reading frame 1 encodes a membrane protein that is dispensable for growth of VZV in vitro.
Varicella-zoster virus (VZV) encodes 69 unique open reading frames, 5 of which do not have herpes simplex virus type 1 (HSV-1) homologs. One of the 5, ORF1, is predicted to encode a protein of 108 amino acids. We identified a 470-base RNA corresponding to ORF1. To determine whether ORF1 encodes a protein, an 11-amino-acid epitope was inserted in frame after the ninth codon of the ORF1 open reading frame. A recombinant virus carrying this epitope expressed a protein that was immunoprecipitated with monoclonal antibody to the epitope. The ORF1 protein was detected in the membrane of infected cells. The size of ORF1 protein expressed in VZV-infected cells was slightly larger than the size expressed by translation in vitro, suggesting that the protein may undergo post-translational modification in infected cells. Insertion of stop codons immediately before the epitope in the ORF1 gene resulted in a recombinant virus that did not express ORF1 protein and that was not growth impaired in cell culture. Thus, ORF1 encodes a protein that localizes to the membrane of VZV-infected cells and that is dispensable for virus growth in vitro.
Medical Virology Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892.
J I
JI
Cohen
K E
KE
Seidel
D000911:Antibodies, Monoclonal; D001483:Base Sequence; D002460:Cell Line; D003360:Cosmids; D018259:Herpesvirus 1, Human / Q000235:genetics; D014645:Herpesvirus 3, Human / Q000235:genetics* / Q000254:growth & development* / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008545:Melanoma; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D009838:Oligodeoxyribonucleotides; D016366:Open Reading Frames; D014176:Protein Biosynthesis; D011499:Protein Processing, Post-Translational; D015183:Restriction Mapping; D017384:Sequence Deletion; D012689:Sequence Homology, Nucleic Acid; D014162:Transfection; D014407:Tumor Cells, Cultured; D014759:Viral Envelope Proteins / Q000096:biosynthesis* / Q000235:genetics
D000911:Antibodies, Monoclonal; D009838:Oligodeoxyribonucleotides; D014759:Viral Envelope Proteins