CYTIP is degraded via the proteasome, and vhs and ICP0 do not contribute to its degradation. Western blot analyses were performed with an antibody specific for CYTIP. Infection with either a vhs deletion mutant virus (A) or an ICP0 deletion mutant (C) leads to degradation of CYTIP with kinetics similar to that of HSV-1 wild-type infection. DCs were infected at a MOI of 1 and harvested at the indicated time points after infection (pi). (B) Inhibition of the proteasome by the addition of 10 μM MG-132 beginning 1 hour after infection completely blocks the loss of CYTIP. Notably, an additional band with higher molecular weight accumulates in MG-132-treated samples. The enrichment of this band in HSV-1–infected DCs indicates a modification that is marked for degradation. Experiments were performed at least 3 times independently, and 1 representative experiment is shown.