FIG. 4.

Budding assay of VP40 proteins containing C-terminal L-domains. Human 293T cells were transfected with pCAGGS vector alone (mock, lanes 1 and 6), pVP40-WT (lane 2), pVP40-cPT/PY (lane 3), pVP40-cPT (lane 4), pVP40-cPY (lane 5), or pVP40Rev (lane 7). Radiolabeled cell extracts (A) and pelleted VLPs (B) were immunoprecipitated with anti-c-myc MAb, and immunoprecipitated proteins were analyzed by SDS-PAGE. (C) Levels of VP40 mutants detected in the VLPs were quantitated by phosphorimager analysis. The level of VP40-WT in VLPs was normalized to 100%, and the relative percentages of VP40 mutants c-PT/PY, c-PT, and c-PY in VLPs are indicated.