FIG. 8.

Schematic representation of possible interactions between E2FBP1 and ICP0 in infected cell nuclei. ICP0 targets E2FBP1 as a HUL-2 substrate to deplete it via the ubiquitin pathway. Contemporaneously with this event, E2FBP1 targets the IE-0 promoter to repress transcription of ICP0 RNA. Target Lys residues in E2FBP1 reside both inside and outside the ARID. The latter sites may be occluded from ubiquitylation as a consequence of REKLES-mediated dimerization. Interactions of PML-NBs with both E2FBP1 and ICP0 are also illustrated. K, Lys residues available for ICP0-mediated ubiquitylation; Ub, ubiquitin moiety.