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Lys-34, dispensable for integrase catalysis, is required for preintegration complex function and human immunodeficiency virus type 1 replication.

Richard Lu·Nick Vandegraaff·Peter Cherepanov·Alan Engelman
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Abstract

Retroviral integrases (INs) function in the context of preintegration complexes (PICs). Two conserved Lys residues in the N-terminal domain of human immunodeficiency virus type 1 (HIV-1) IN were analyzed here for their roles in integration and virus replication. Whereas HIV-1(K46A) grew like the wild type, HIV-1(K34A) was dead. Yet recombinant IN(K34A) protein functioned in in vitro integration assays, and Vpr-IN(K34A) efficiently transcomplemented the infectivity defect of an IN active site mutant virus in cells. HIV-1(K34A) was therefore similar to a number of previously characterized mutant viruses that failed to replicate despite encoding catalytically competent IN. To directly analyze mutant PIC function, a sensitive PCR-based integration assay was developed. HIV-1(K34A) and related mutants failed to support detectable levels (<1% of wild type) of integration. We therefore concluded that mutations like K34A disrupted higher-order interactions important for PIC function/maturation compared to the innate catalytic activity of IN enzyme.

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Amino Acid SubstitutionHIV IntegraseHIV-1MucoproteinsMutation, MissensePolymerase Chain ReactionReverse TranscriptionVirus ReplicationJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, U.S. Gov't, P.H.S.

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Richard Lu, Nick Vandegraaff, Peter Cherepanov, Alan Engelman. 2005. Lys-34, dispensable for integrase catalysis, is required for preintegration complex function and human immunodeficiency virus type 1 replication.. https://doi.org/10.1128/jvi.79.19.12584-12591.2005

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