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An expanded model of replicating human immunodeficiency virus reverse transcriptase.

B M Wöhrl·C Tantillo·E Arnold·S F Le Grice
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Abstract

Replication complexes containing wild-type and RNase H-deficient p66/p51 human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT) were analyzed by DNase I and S1 footprinting. While crystallography and chemical footprinting data demonstrate that 15-18 bases of primer and template occupy the DNA polymerase and RNase H active centers, enzymatic footprinting suggests that a larger portion of substrate is encompassed by the replicating enzyme. Independent of the position of DNA synthesis arrest, template nucleotides +7 to -23 and primer nucleotides -1 to -25 are nuclease resistant. On both DNA strands, position -20 remains accessible to DNase I cleavage, suggestive of an alteration in nucleic acid structure between exiting the RNase H catalytic center and leaving the C-terminal p66 domain. A model of HIV-1 RT containing an extended single-stranded template and duplex region was constructed on the basis of the structure of an RT/DNA complex. Mapping of footprint data onto this model shows consistency between biochemical and structural data, implicating a contribution from domains proximal to the catalytic centers.

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Base SequenceBinding SitesDNA PrimersDNA ReplicationDNA, ViralDNA-Directed DNA PolymeraseDeoxyribonuclease IHIV Reverse TranscriptaseHIV-1Models, MolecularMolecular Sequence DataNucleic Acid ConformationProtein ConformationProtein Structure, SecondaryRNA-Directed DNA PolymeraseRecombinant ProteinsRibonuclease HSubstrate SpecificityTemplates, GeneticJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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B M Wöhrl, C Tantillo, E Arnold, S F Le Grice. 1995-04-25. An expanded model of replicating human immunodeficiency virus reverse transcriptase.. https://doi.org/10.1021/bi00016a005

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