FIG. 9.
A model of the interaction of ICP22 with cdc25C in the context of assembly of the cdc2/UL42/topoisomerase IIα complex and transcription of late genes. The model presented in this figure is an update of the model initially published by Advani et al. (4). The top part of the figure describes the formation of the UL42/cdc2/topoisomerase II complex essential for efficient transcription of the subset of γ2 proteins exemplified by UL38, UL41, and US11. The bottom panel illustrates at least in part the complexes of viral proteins involved in DNA synthesis on both strands of viral DNA and some of the proteins involved in the transcription of newly synthesized DNA. The studies presented in this and earlier reports indicate that several proteins in this complex (ICP22, UL13, and US3 cdc25C) play a role in enabling efficient transcription of late genes. The phosphates shown in red are attributed to viral kinases.