VLP samples were collected from cells transfected with wt HIVgpt (A), HIVgpt-AKTPH (B), HIVgpt-PLCPH (C), or HIVgpt-PKCCBD (D), and either untreated or treated with 1 μM PMA (+PMA). Proteins in Gag-normalized samples were fractionated by SDS-PAGE, and detected by immunoblotting using an anti-HIVRT primary antibody. Size marker mobilities, as well as 66 kDa RT-RH and 51 kDa RT bands, are indicated. Note that no other bands were detected with the anit-RT antibody, but that similarly sized bands for the MBD variants (B-D) were detected in parallel immunoblots with an anti-HIVPR antibody.