FIG 2.

HPV-31 E2 Y102E does not bind TopBP1. (A and B) Lysates of cells transfected with FLAG-HPV-31 E2 (WT, Y102E, and Y102F) were immunoprecipitated either with an antibody to TopBP1 (A) or FLAG (B). (C) Diagram of lysate fractionation performed in parts D and E. (D) HEK 293TT cells transfected with FLAG-HPV-31 E2 WT or Y102E were lysed and fractionated according to the scheme shown in C, run on a gel, and blotted with FLAG, tubulin, histone, and p53 antibodies. (E) Ratio of nuclear matrix bound (lane 4 in D) over soluble (lane 1) HPV-31 E2 from three experiments, normalized to WT. Y102E was significantly different from WT with P < 0.005, and means are expressed ± SEM.