Total RNA was extracted with TRIzol (Invitrogen) and treated with Turbo DNA-free reagent (Ambion) to remove genomic DNA contaminants. cDNA was reverse transcribed from total RNA with random hexamer primers using the High Capacity cDNA reverse transcription kit (Applied Biosystems). cDNA was quantified using SYBR Advantage qPCR Premix (Clontech) and primers for the cellular genes geminin, APC4, APC5, and GAPDH (glyceraldehyde-3-phosphate dehydrogenase) as an internal control (see below). cDNA from infected cells was used to generate a standard curve for each gene examined. The standard curve was then used to calculate the relative amount of specific RNA present in a sample.