Site-directed mutagenesis of HIV-1 integrase demonstrates differential effects on integrase functions in vitro.

摘要: The retroviral integrase (IN) protein is essential for integration of DNA into the host cell genome. To identify functional domains within and to assess importance conserved residues, we performed site-directed mutagenesis HIV-1 IN analyzed mutants in vitro IN-mediated activities: 3' processing (att site-specific nuclease activity), strand transfer (the joining att site oligonucleotides target DNA), disintegration reverse transfer), selection. Changing residue His-16 either Cys or Val a proposed zinc-finger region had minimal effect on activities. Alteration two highly amino acid Asp-116-->Ile Glu-152-->Gly, each resulted complete nearly loss processing, transfer, disintegration, whereas alteration another residue, Trp-235-->Glu, no demonstrable any activities vitro. Two mutants, Asp-64-->Val Arg-199-->Cys delta, demonstrated differential effects has activity yet maintains at diminished level. which lacks part carboxyl terminus IN, impaired without activity. Use selection assay showed that all our with maintain same pattern as wild type IN. We conclude not residues are vitro, zinc coordination by domain may be required assayed, single can yield activities, naked necessarily altered changes