title: Maintenance of an unusual polypurine tract in HIV-2: stability to passage in culture.
abstract: A stretch of purine residues, the polypurine tract (PPT), is found in all retroviruses and is used to initiate plus-strand DNA synthesis. While the PPT of most lentiviruses is a homogeneous sequence of purine residues, the PPT of some isolates of the human and simian immunodeficiency viruses is interrupted with a single pyrimidine residue. The ROD strain of human immunodeficiency virus type 2 (HIV-2) has such a pyrimidine-containing variant PPT. Virus generated from an infectious molecular clone, pROD10, was used to infect two CD4-positive T-cell lines, H9 and CEM. The sequence of the PPT was determined after two passages. From both cell lines, the variant PPT was retained, demonstrating that the presence of a pyrimidine in the PPT was fully functional and that there was no strong selection for an all-purine PPT.
authors.affiliation: ABL-Basic Research Program, Frederick Cancer Research and Development Center, Building 539, Frederick, Maryland 21702, USA.
authors.forename: V
authors.initials: V
authors.lastname: Lauermann
authors.forename: S H
authors.initials: SH
authors.lastname: Hughes
authors.forename: K W
authors.initials: KW
authors.lastname: Peden
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D016384:Consensus Sequence; D017931:DNA Primers; D004279:DNA, Viral / Q000737:chemistry*; D015693:Gene Products, nef / Q000737:chemistry; D015754:Genes, nef; D014644:Genetic Variation; D015498:HIV-2 / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D008957:Models, Genetic; D016133:Polymerase Chain Reaction; D011533:Proviruses / Q000235:genetics; D011687:Purines; D012194:RNA-Directed DNA Polymerase / Q000378:metabolism; D054311:nef Gene Products, Human Immunodeficiency Virus
chemical_list: D017931:DNA Primers; D004279:DNA, Viral; D015693:Gene Products, nef; D011687:Purines; D054311:nef Gene Products, Human Immunodeficiency Virus; D012194:RNA-Directed DNA Polymerase