FIG. 5.

In vitro replication assays for the effects of the purified FKBP52 protein, with and without phosphorylation by CK II or EGFR-PTK, on AAV second-strand DNA synthesis. These assays were carried out as described in Materials and Methods. The radiolabeled AAV hairpin (HP) DNA template (lane 1) (shown schematically as the upper figure on the left) was readily converted into its duplex counterpart (shown schematically as the lower figure on the left) following second-strand DNA synthesis by the Klenow enzyme (lane 2). Prior incubation with the dephosphorylated FKBP52 protein had no effect (lane 3), while CK II-phosphorylated FKBP52 inhibited second-strand DNA synthesis by ≈40% (lane 4). CK II in the absence of FKBP52 had no effect (lane 5). FKBP52 phosphorylated by EGFR-PTK inhibited viral second-strand DNA synthesis by >90% (lane 6), and EGFR-PTK alone had no effect (lane 7). BSA, bovine serum albumin; +, present; −, absent.