title: Contribution of NF-kappa B and Sp1 binding motifs to the replicative capacity of human immunodeficiency virus type 1: distinct patterns of viral growth are determined by T-cell types.
abstract: Starting with a replication-incompetent molecular clone of human immunodeficiency virus type 1, lacking all the NF-kappa B and Sp1 binding sites present in the native long terminal repeat (LTR), proviruses containing reconstructed LTRs with individual or combinations of NF-kappa B and Sp1 elements were generated and evaluated for their capacity to produce virus progeny following transfection-cocultivation. Virus stocks obtained from these experiments exhibited a continuum of replicative capacities in different human T-cell types depending on which element(s) was present in the LTR. For example, in experiments involving proviral clones with LTRs containing one or two NF-kappa B elements (and no Sp1 binding sites), a hierarchy of cellular permissivity to virus replication (peripheral blood lymphocytes = MT4 greater than H9 greater than CEM greater than Jurkat) was observed. Of note was the associated emergence of second-site LTR revertants which involved an alteration of the TATA box. These results suggest that the human immunodeficiency virus type 1 LTR possesses functional redundancy which ensures virus replication in different T-cell types and is capable of changing depending on the particular combination of transcriptional factors present.
authors.affiliation: Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland 20892.
authors.forename: E K
authors.initials: EK
authors.lastname: Ross
authors.forename: A J
authors.initials: AJ
authors.lastname: Buckler-White
authors.forename: A B
authors.initials: AB
authors.lastname: Rabson
authors.forename: G
authors.initials: G
authors.lastname: Englund
authors.forename: M A
authors.initials: MA
authors.lastname: Martin
mesh_terms: D001483:Base Sequence; D002460:Cell Line; D004261:DNA Replication; D004279:DNA, Viral / Q000096:biosynthesis / Q000737:chemistry*; D004742:Enhancer Elements, Genetic; D015497:HIV-1 / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D006801:Humans; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D016328:NF-kappa B / Q000235:genetics* / Q000378:metabolism; D016133:Polymerase Chain Reaction; D011533:Proviruses / Q000235:genetics; D012367:RNA, Viral / Q000737:chemistry; D012091:Repetitive Sequences, Nucleic Acid; D016329:Sp1 Transcription Factor / Q000235:genetics* / Q000378:metabolism; D013601:T-Lymphocytes / Q000382:microbiology*; D014162:Transfection; D014779:Virus Replication
chemical_list: D004279:DNA, Viral; D016328:NF-kappa B; D012367:RNA, Viral; D016329:Sp1 Transcription Factor