Figure 1.

Random mutagenesis of HIV-1 IN and mutant selection strategy. The construction of a library of HIV-1 IN variants containing random nucleotide substitutions in the V₁₅₁E₁₅₂S₁₅₃ region is described in Materials and Methods. The different mutated IN encoding genes were introduced into the expression vector pHIVSF2IN to express the corresponding mutated INs in the IN-sensitive yeast strains AB2 and W839–5C. The yeast lethal assay was performed under the conditions described in Materials and Methods and the clones presenting lethality were selected.