title: The human herpesvirus-8 ORF 57 gene and its properties.
abstract: Human herpesvirus-8 (HHV-8) is a gamma(2) lymphotropic herpesvirus associated with Kaposi's sarcoma, a major neoplasm of AIDS patients, and with other AIDS-related neoplasms. The HHV-8 ORF 57 gene is conserved throughout the herpesvirus family and has a herpes simplex virus type 1 homologue, IE63 (also termed ICP27), which is an essential regulatory protein and acts at both transcriptional and post-transcriptional levels. We show that, contrary to the published HHV-8 sequence, which predicts a protein of 275 amino acids, the ORF 57 gene is spliced, contains a single intron and encodes a protein of 455 amino acids. For several gammaherpesviruses examined, the upstream coding exon is 16-17 amino acids in length and is rich in methionine residues. When ORF 57 was fused to the gene for enhanced green fluorescent protein (EGFP), the fusion protein exhibited a punctate nuclear distribution that co-localized with the cellular splicing factor SC-35. Unlike the IE63-EGFP fusion protein, ORF 57-EGFP did not shuttle from the nucleus to the cytoplasm in the presence of actinomycin D. However, ORF 57-EGFP was capable of shuttling from a transfected monkey nucleus to a recipient mouse nucleus in an interspecies heterokaryon assay. These data indicate that HHV-8 ORF 57 and IE63 possess certain common properties.
authors.affiliation: Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA2.|Institute of Virology, University of Glasgow, Church Street, Glasgow G11 5JR, UK1.
authors.forename: Leonard J
authors.initials: LJ
authors.lastname: Bello
authors.affiliation: Institute of Virology, University of Glasgow, Church Street, Glasgow G11 5JR, UK1.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Davison
authors.affiliation: Department of Medical Microbiology, University of Liverpool, UK3.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Glenn
authors.affiliation: Molecular Medicine Unit, St James University Hospital, Leeds, UK4.
authors.forename: Adrian
authors.initials: A
authors.lastname: Whitehouse
authors.affiliation: Institute of Virology, University of Glasgow, Church Street, Glasgow G11 5JR, UK1.
authors.forename: Nikki
authors.initials: N
authors.lastname: Rethmeier
authors.affiliation: Department of Medical Microbiology, University of Liverpool, UK3.
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Schulz
authors.affiliation: Institute of Virology, University of Glasgow, Church Street, Glasgow G11 5JR, UK1.
authors.forename: J
authors.initials: J
authors.lastname: Barklie Clements
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D018076:DNA, Complementary; D003609:Dactinomycin / Q000494:pharmacology; D003851:Deoxyribonucleases / Q000378:metabolism; D005091:Exons / Q000235:genetics; D005814:Genes, Viral; D019288:Herpesvirus 8, Human / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D007438:Introns / Q000235:genetics; D051379:Mice; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics*; D016133:Polymerase Chain Reaction; D012326:RNA Splicing / Q000235:genetics; D012367:RNA, Viral / Q000235:genetics / Q000302:isolation & purification; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D017422:Sequence Analysis, DNA; D014162:Transfection
chemical_list: D018076:DNA, Complementary; D012367:RNA, Viral; D011993:Recombinant Fusion Proteins; D003609:Dactinomycin; D003851:Deoxyribonucleases