Infection did not result in a total shift of the Chk2 species into the slower migrating form, as was found in cells treated with the radiomimetic neocarzinostatin (NCS) (Figure 1A, panel c, lane 7), likely because during infection of a para-synchronous population not all cells enter S-phase and support MVM replication in a perfectly uniform manner. This evidence concerns the gene CHEK2 and infection.