Fig. 3.

NSUN2 depletion leads to an enhanced up-regulation of type I IFN signaling and antivirus immune response, in which it also controls the m⁵C methylation in some A549 host RNAs. (A) (Left) location of 20 m⁵C sites within RSV genome RNA. The x axis shows the m⁵C site position in RSV genome; the y axis shows the m⁵C site mutation level. (Right) Number of m⁵C sites in each RSV gene. (B) Distribution of NSUN2-regulated m⁵C sites in major RNA species from A549 host RNA (shared by both RSV-infected and VSV-infected cells). (C) Mutation levels of NSUN2-regulated m⁵C sites in cytoplasmic tRNAs from NSUN2-KO A549 cells vs. WT cells. P values were determined using two-tailed t test for paired samples (****P < 0.0001). (D–G) Mutation levels of one m⁵C site in RPPH1 (D), two m⁵C sites in snoRNA 62A and 62B (E), one m⁵C site in scaRNA2 (F), and one m⁵C site in vault RNA (vtRNA1-1) (G) from NSUN2-KO A549 cells vs. WT cells. For (D)–(G), mean values ± SD are shown; n = 2. (H) Enriched GO clusters of up-regulated genes in virus-infected NSUN2-KO A549 cells (vs. virus-infected WT A549 cells). The clusters are ranked by P value.