The human herpesvirus-8 ORF 57 gene and its properties.
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.
Bello
Leonard J
LJ
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.
Davison
Andrew J
AJ
Institute of Virology, University of Glasgow, Church Street, Glasgow G11 5JR, UK1.
Glenn
Mark A
MA
Department of Medical Microbiology, University of Liverpool, UK3.
Whitehouse
Adrian
A
Molecular Medicine Unit, St James University Hospital, Leeds, UK4.
Rethmeier
Nikki
N
Institute of Virology, University of Glasgow, Church Street, Glasgow G11 5JR, UK1.
Schulz
Thomas F
TF
Department of Medical Microbiology, University of Liverpool, UK3.
Barklie Clements
J
J
Institute of Virology, University of Glasgow, Church Street, Glasgow G11 5JR, UK1.
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
D018076:DNA, Complementary; D012367:RNA, Viral; D011993:Recombinant Fusion Proteins; D003609:Dactinomycin; D003851:Deoxyribonucleases