The primary antibodies used in this study included anti-b actin (AC-15, Abcam); anti-HA (HA.11, Covance); anti-GFP (3E6 and A6455, Invitrogen); anti-APC3 (AF3.1, Santa Cruz and 610454, BD); anti-APC8 (6114, Biolegend); anti-APC4 (A301-176A, Bethyl laboratories); anti-APC5 (A301-026A, Bethyl laboratories); antigeminin (sc-13015, Santa Cruz); anti-Cdh1 (DH01, Calbiochem); anti-cyclin B1 (ms868 P1, Thermo-Scientific); anti-UL21a [29] ; anti-IE2 (mAB8140, Chemicon); and anti-IE1 and anti-pp28 (generous gifts from Thomas Shenk, Princeton University) [45] . Phosphonoacetic acid (PAA), MG132, tetracycline, gancyclovir (GCV), and propidium iodide (PI) were purchased from Sigma-Aldrich. Lipofectamine 2000 and Protein A-conjugated Dynabeads were purchased from Invitrogen.