Fig. 4

FENDRR affects DRP1 DNA methylation by forming RNA–DNA triplex with DRP1 promoter. a Longtarget predicted binding sites of FENDRR and DRP1 promoter. b Two triplex forming oligonucleotides (TFOs) within the FENDRR probes and negative control probes were used for ChIRP assay. Purified DNA was analyzed by qPCR (n = 5). c HPAECs were cotransfected with a luciferase reporter construct carrying wild-type (WT) or mutant (MUT) DRP1 promoter with FENDRR binding site and FENDRR or NC. Luciferase activities were measured via a dual luciferase assay (n = 5). d HNADOCK Server predicted the 3D structural docking of FENDRR and DRP1 promoter. e RNA–DNA triplex formed by TFO2 of FENDRR and DRP1 promoter detected by EMSA. f Schematic of the CpG islands within the DRP1 promoter. g DRP1 promoter methylation status at specific sites in HPAECs transfected with FENDRR overexpression plasmid detected by MSP. Each datapoint in the figure represents a unique biological replicate. All values are presented as the mean ± SD. Statistical analysis was performed with Student’s t-test. NOR: normoxic; HYP: hypoxic; NC: negative control; M: methylation; U: unmethylation; ns: no significant. ***P < 0.001 compared with NC