title: Genetic variability and function of the long terminal repeat from syncytium-inducing and non-syncytium-inducing human immunodeficiency virus type 1.
abstract: We analyzed sequence variability and function of the long terminal repeat (LTR) from syncytium-inducing (SI) and non-syncytium-inducing (NSI) HIV-1. Twenty LTR DNA clones were obtained by polymerase chain reaction amplification and molecular cloning from short-term cultures of SI and NSI viruses from an AIDS patient and two asymptomatic individuals, respectively. All the LTR clones tested contained multiple nucleotide changes (mostly G-to-A transitions), compared to the subtype B consensus sequence, which were clustered within the negative regulatory element, including NF-AT, USF, and TCF-1 alpha binding sites. The core promoter/TAR region sequences were highly conserved. The basal and Tat-mediated transcriptional activities of selected LTR clones tested were 0.1 to 1 and 0.2 to 0.5 times that of the control, respectively, regardless of the SI or NSI origin of the clones. Phylogenetic analysis revealed interi-solate sequence divergence in the LTR that was similar but not identical to previously analyzed vif sequences from the same samples. In particular, the inter-isolate distances from reference sequences differed for the LTR and vif. This raises the possibility that recombination occurred between corresponding LTR and vif loci of the quasi-species present in the isolates described here.
authors: Molecular Virology Laboratory, St. Luke's-Roosevelt Hospital Center, Columbia University, New York, New York 10019, USA.
authors: M
authors: M
authors: Simm
authors: W
authors: W
authors: Chao
authors: O
authors: O
authors: Pekarskaya
authors: P
authors: P
authors: Sova
authors: P
authors: P
authors: Gupta
authors: R
authors: R
authors: Balachandran
authors: D J
authors: DJ
authors: Volsky
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000821:virology; D001483:Base Sequence; D001665:Binding Sites; D003001:Cloning, Molecular; D004252:DNA Mutational Analysis; D004279:DNA, Viral / Q000235:genetics*; D019143:Evolution, Molecular; D016341:Genes, vif; D014644:Genetic Variation; D015726:Giant Cells; D015658:HIV Infections / Q000821:virology; D015497:HIV-1 / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D006801:Humans; D008969:Molecular Sequence Data; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D011995:Recombination, Genetic; D012045:Regulatory Sequences, Nucleic Acid; D012091:Repetitive Sequences, Nucleic Acid; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D004279:DNA, Viral; D014157:Transcription Factors