Lys-34, dispensable for integrase catalysis, is required for preintegration complex function and human immunodeficiency virus type 1 replication.
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.
Lu
Richard
R
Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, 44 Binney Street, Boston, MA 02115, USA.
Vandegraaff
Nick
N
Cherepanov
Peter
P
Engelman
Alan
A
D019943:Amino Acid Substitution; D019427:HIV Integrase / Q000737:chemistry / Q000235:genetics* / Q000502:physiology*; D015497:HIV-1 / Q000235:genetics* / Q000502:physiology*; D009088:Mucoproteins / Q000235:genetics / Q000502:physiology*; D020125:Mutation, Missense; D016133:Polymerase Chain Reaction; D048348:Reverse Transcription; D014779:Virus Replication
D009088:Mucoproteins; C010393:lysin, gastropoda; D019427:HIV Integrase