Fig. 5.

Accumulation of immunostimulatory 5′-ppp-vtRNAs during lytic reactivation. a Predicted secondary structure of vtRNAs generated by RNAfold. b SYBR-Gold staining of in vitro transcribed vtRNAs with or without CIP treatment. c HCT116 ISG54-luciferase reporter cells were transfected with 100 ng in vitro transcribed vtRNAs with or without CIP treatment. Cells were harvested 24 h posttransfection and subjected to luciferase assay. Mock indicated cells without RNA transfection and was set as 1. d BC-3 cells were reactivated for 3 days and expression of DUSP11 was quantified by RT-qPCR. L latency, D1–D3 lytic reactivation for 1 day to 3 days. The DUSP11 expression was normalized to the level of 18S rRNA and L was set as 1. e Cell lysates were prepared from BC-3 cells described in (d) and DUSP11 protein levels were monitored by Western blot. GAPDH was run as a loading control. f Latent and lytic BC-3 cells were subjected to RNAP II ChIP-qPCR analysis. Signals were normalized to input. g Total RNA, extracted from latent or 72 h postreactivation BC-3 cells, was subjected to splint-ligation to quantify 5′-monophosphorylated vtRNAs. * denotes a product of adapter-adapter ligation (see Supplementary Fig. 7). h HCT116 ISG54-luciferase reporter cells were transfected with vtRNA or U1 RNA isolated by antisense oligonucleotide affinity selection from either latent or lytic BC-3 cells. Cells were harvested 12 h posttransfection and subjected to luciferase assay. Mock indicated cells without RNA transfection and was set as 1. Error bars in all panels represent mean ± SD from three independent experiments. p Values were determined by the Student’s t test, ^*p < 0.05, ^**p < 0.01