Fig. 8: tRF-3b modification by TRMT6/61A is important for maintaining the unfolded protein response.

a GSEA from RNA-seq in BLCA and HEK293T siTRMT61A data reveals Unfolded Protein Response (UPR) as a candidate pathway regulated by TRMT6/61A. b Gene Set Enrichment Analysis shows UPR as positively enriched pathway in BLCA tumor compared to the paired normal samples (n = 5, x-axis: ranking based on differential analysis from upregulated genes to downregulated genes). c TRMT6/61A regulates UPR response by UPR reporter assay in HEK293T and the BLCA tumor cell line T24. Three tandem repeats of ATF6 response element ERSE2 is inserted in the Firefly luciferase gene promoter. UPR response is measured by Firefly luciferase signals divided by Renilla luciferase signals (on co-transfected plasmid) and normalized to siCtrl basal level. Tunicamycin (Tm) is added to trigger UPR response. d m¹A status on tRF-3 regulates UPR reporter output. tRF-3004b synthetic mimic and UPR reporter plasmid (same as above) are co-transfected into HEK293T. NT1 and NT2 are non-targeting control RNAs. e, f tRF-3004 targets have increased levels after tRF-3004 knock-down and tunicamycin treatment in HEK293T cells. Data are based on c, d n = 3 independent experiments, e, f n = 2 independent experiments. c, d Data represent mean ± SD, p value based on student’s t test (two-tailed paired sample, *p < 0.05, **p < 0.01). Exact p values from left to right: c 0.00019, 0.00409, 0.00088, and 0.00062; d 0.00013, 0.00066. See also Supplementary Fig. 7. Source data are provided as a Source Data file.