FIG. 2.

The impact of Pol-processing mutations on HIV-1 virion protein composition and genomic RNA dimer maturation. (A) Schematic representation of HIV-1 and Pol PDMs 1, 2, and 3 is given. Constructs were generated by insertion of Thr and Arg codons into the indicated cleavage sites by PCR mutagenesis. Pol PDM 1 had a Thr and Arg insertion between the RT p51-RNase H cleavage site indicated by [] Pol PDM 2 contains Thr and Arg at the RT-IN cleavage site indicated by [] Pol PDM 3 contained Thr and Arg insertions at both p51-RNase H and RT-IN cleavage sites indicated by []. (B) Western blot analysis was performed on WT, PR_UAG (lacking in Pol proteins), and Pol PDMs 1, 2, and 3. Proteins from purified virions were resolved by 10% Tris-glycine SDS-PAGE and then probed with pooled sera from HIV-1-infected individuals. (C) Virion RNA was resuspended in RNA dimerization buffer and heat denatured for 10 min at the indicated temperatures. Dimers and monomers were electrophoresed in a 1% native agarose gel and probed with an HIV-1-specific riboprobe as described in Materials and Methods.