MCL1 and infection: This loss was not seen at the mRNA level (where there was even some increase during infection (Supplementary Figure S1A and B)) and may in part be due to the induction of the Mcl-1-antagonist Noxa, which can trigger the degradation of Mcl-1,21 and which is known to be upregulated in the response of HeLa cells to MVA infection (Figure 1a).22 Noxa was lost again at later stages of infection, possibly indicating reduced synthesis or co-degradation with Mcl-1.