title: Naturally occurring accessory gene mutations lead to persistent human immunodeficiency virus type 1 infection of CD4-positive T cells.
abstract: Proviral DNA from cells surviving severe but transient cytopathic effects, mediated by infection with recombinant human immunodeficiency virus type 1 (HIV-1) carrying a single gene mutation at vif, vpr, or vpu, was characterized by use of HIV-1-specific primer pairs in a two-step PCR. Deletion mutations were detected in a region that spanned the vif and vpr open reading frames. Cloning and sequencing of the amplified DNA from this region revealed frequent large deletions in a limited number of nucleotide positions. Analyses of the deletions suggested that (i) genetic recombination, (ii) template-primer slippage, and (iii) misalignment of the growing point during reverse transcription of the HIV-1 genome might be the mechanisms that generated the mutations. Apart from the large deletions, smaller deletions that gave frameshift mutations in vif and/or vpr prevailed. In addition, cells infected with a triple mutant defective in vif, vpr, and vpu did not show any cytopathic effect. Thus, mutations generating multiple accessory gene defects during HIV-1 replication correlate with viral persistence and loss of cytopathogenicity.
mesh_terms: D001483:Base Sequence; D015496:CD4-Positive T-Lymphocytes / Q000821:virology*; D002461:Cell Line, Transformed; D017931:DNA Primers; D004279:DNA, Viral / Q000235:genetics; D003673:Defective Viruses / Q000235:genetics* / Q000276:immunology; D016368:Frameshift Mutation; D016341:Genes, vif; D016334:Genes, vpr; D016338:Genes, vpu; D016679:Genome, Viral; D015497:HIV-1 / Q000235:genetics* / Q000472:pathogenicity / Q000502:physiology; D006801:Humans; D007700:Kinetics; D008969:Molecular Sequence Data; D009154:Mutation; D015345:Oligonucleotide Probes; D011533:Proviruses / Q000235:genetics / Q000276:immunology; D017384:Sequence Deletion; D013601:T-Lymphocytes; D013997:Time Factors; D014779:Virus Replication / Q000235:genetics*
chemical_list: D017931:DNA Primers; D004279:DNA, Viral; D015345:Oligonucleotide Probes