Fig. 7

FTO-IT1 was transcriptionally regulated by c-Myc under hypo-glucose condition. A Expressions of FTO-IT1 in HepG2/MHCC97H cells were detected under hypoxia and acidic conditions compared with normal condition. B Expressions of FTO-IT1 in HepG2/MHCC97H cells were detected under 1% FBS, FBS free, glutamine-free, serine-free, glucose low (1 mmol/L) and glucose-free conditions compared with normal condition. C Cells were cultured with sequentially decreased concentration of glucose conditions (25, 10, 5, 2.5, 1, 0.5 mmol/L), then the FTO-IT1 level was evaluated. D Cells were exposed to low glucose condition (1 mmol/L) for 0, 6, 12, 24 and 48 h, then the FTO-IT1 level was evaluated. E Cells were cultured with low glucose conditions (1 mmol/L), then the mRNA and protein level of c-Myc were evaluated. F Schematic illustration of the proximal region of the FTO-IT1 promoter and three putative c-Myc binding sites using JASPAR database (https://jaspar.genereg.net). TSS, Transcriptional start site. G ChIP assays were performed to verify the binding capacity between c-Myc and the three binding sites of FTO-IT1 promoter in HepG2 cells (left). Then the qRT-PCR products were separated by 2% agarose gel electrophoresis (right). H The potential binding site was mutated as indicated. WT, wild-type; MUT, mutation. I WT or MUT FTO-IT1 promoter sequence luciferase reporter activity in HepG2 cells transfected with or without sic-Myc were measured by luciferase reporter assay. Renilla luciferase served as a control. J WT or MUT FTO-IT1 promoter sequence luciferase reporter activity in Huh7 cells transfected with or without overexpression c-Myc plasmid were measured by luciferase reporter assay. K, L The level of FTO-IT1 after knocking down (K) or overexpressing (L) c-Myc