FIGURE 2.

Nuclear body-enriched preparation contains Nrf2 and components of PML-NBs. Whole cell lysate (W), prepared from HepG2 cell cultures treated with As₂O₃ (2 μm) for 4 h, was separated into cytoplasmic (C) and partially purified nuclear pellet (18). Beginning with the partially purified nuclear pellet, nuclear body-enriched fraction (NB) was prepared according to the protocol described by He et al. (23) as modified by Vertegaal et al. (24). The final pellet was suspended in 100 μl of buffer containing equal volumes of Tris-HCl solution (pH 6.8) and 2× SDS sample buffer. The cytoplasmic, whole cell lysate, and NB fractions were then blotted for the proteins indicated in A and B. *, modified (sumoylated) PML protein.