Fig. 3. Schematic representation of PML bodies in the nucleoplasm. PML bodies consist of smaller PML-containing subunits that interact with high-order chromatin fibers possibly through MARs. PML bodies function to control the concentration of transcriptional activators and repressors within the local chromatin environment. Upon stimulation of cellular pathways, these factors are released from PML bodies and bind enhancer/promoter elements in the surrounding chromatin. Upon infection with double-stranded DNA viruses such as HCMV, viral genomes localize to the surface of PML bodies. This targeting is mediated through cellular factors such as Daxx, which are normally associated with PML bodies, and viral tegument proteins, such as pp71.