FIG. 1.

Comparative demodification and degradation of PML and Sp100 induced by ICP0 during HSV-1 infection. HFL cells were mock infected (lane M) or infected at 10 PFU per cell with HSV-1 strain 17syn+ in the absence (lane wt) or presence (lane MG132 wt) of proteasome inhibitor MG132 (5 μM final concentration) and the ICP0 mutant viruses FXE, E52X, M1, and D14, as indicated. The cells were harvested for Western blotting 4 h postabsorption. Western blots were probed for PML using MAb 5E10 at a dilution of 1/5 (upper panel), and the filter was then stripped and reprobed for Sp100 using rabbit serum SpGH at a dilution of 1/1,000 (lower panel). To the left of the panels, the short dashes indicate the major SUMO-1-modified isoforms of PML and Sp100 and the longer ones indicate the major, presumed unmodified, forms of the proteins. The positions of the 220-, 97-, and 66-kDa molecular mass markers are indicated to the right.