title: The divergence between two oncogenic Herpesvirus saimiri strains in a genomic region related to the transforming phenotype.
abstract: Herpesvirus saimiri strains can be divided into at least three subgroups (A, B, C) based on sequence divergence at the left end of viral unique sequence DNA. Strains of subgroups A and C are highly oncogenic and readily transform simian T-lymphocytes in vitro to interleukin-2 independent growth, while subgroup B strains do not. A left terminal reading frame of a H. saimiri subgroup A strain was shown previously to correlate with the oncogenic phenotype and in vitro transforming potential; the deduced polypeptide was termed STP-A. Furthermore, this same region contains an open reading frame (ORF) for dihydrofolate reductase (DHFR) and genes for five virus-specific U RNAs (HSURs). We now show by sequence analysis of the corresponding region in a subgroup C strain that DHFR and HSUR genes are present in both virus subgroups; however, no sequence homologous to the STP-A reading frame was found in this subgroup C virus. At a position and orientation similar to STP-A, two ORFs were found for peptides sharing a putative transmembrane domain. One of them encodes a peptide with collagen-like repetitions. In addition to the lack of similarity to STP-A, these two reading frames also did not show any similarity to known oncogenes. The organization of sequences at the left junction of unique L- and repetitive H-DNA of H. saimiri suggests frequent recombinational events, possibly accelerating the uptake of foreign genes by the virus.
authors.affiliation: Institut für Klinische und Molekulare Virologie, Universität Erlangen-Nürnberg, Federal Republic of Germany.
authors.forename: B
authors.initials: B
authors.lastname: Biesinger
authors.forename: J J
authors.initials: JJ
authors.lastname: Trimble
authors.forename: R C
authors.initials: RC
authors.lastname: Desrosiers
authors.forename: B
authors.initials: B
authors.lastname: Fleckenstein
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D002471:Cell Transformation, Neoplastic / Q000235:genetics*; D002472:Cell Transformation, Viral / Q000235:genetics*; D003001:Cloning, Molecular; D004279:DNA, Viral / Q000235:genetics*; D006567:Herpesvirus 2, Saimiriine / Q000145:classification / Q000235:genetics*; D008969:Molecular Sequence Data; D009856:Oncogene Proteins, Viral / Q000235:genetics*; D010641:Phenotype; D010957:Plasmids; D016133:Polymerase Chain Reaction; D012342:RNA, Small Nuclear / Q000235:genetics; D012367:RNA, Viral / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid; D013762:Tetrahydrofolate Dehydrogenase / Q000235:genetics
chemical_list: D004279:DNA, Viral; D009856:Oncogene Proteins, Viral; D012342:RNA, Small Nuclear; D012367:RNA, Viral; C064364:STP protein, Herpesvirus saimiri; D013762:Tetrahydrofolate Dehydrogenase