The decrease of IRF3 mRNA and protein levels correlates with the reduced SNRNP200 mRNA and protein levels as well as with the reduced expression of effector genes upon infection in KD cells (S5 Fig); however, the experiments did not identify splicing variants to explain the reduced IRF3 protein levels (S7 Fig), ruling out an alternative splicing regulation of IRF3 mRNA for SNRNP200 depleted cells. This evidence concerns the gene IRF3 and infection.