Fig. 6: TET1 acts as a coactivator of HIF1α to promote CK2B transcription.
From: Hypoxia switches TET1 from being tumor-suppressive to oncogenic
CK2B mRNA expression in 8505C (A) and C643 (B) cells with the indicated treatments by qRT-PCR assay (n = 3 biological replicates). Western blot analysis of TET1, HIF1α and CK2β in 8505C (C) and C643 (D) cells with the indicated treatments. CK2B mRNA expression in 8505C (E) and C643 (F) cells with the indicated treatments by qRT-PCR assay (n = 3 biological replicates). Dual-luciferase reporter system was performed to determine CK2B promoter activity in 8505C (G) and C643 (H) cells with the indicated treatments (n = 3 biological replicates). I ChIP-qPCR assay showing the binding of HIF1α to CK2B promoter in 8505C cells under hypoxia (n = 3 biological replicates). J Co-IP assay showing the interaction between HIF1α and TET1 in C643 cells under hypoxia. K ChIP-qPCR assay showing the binding of TET1 to CK2B promoter in C643 cells under hypoxia (n = 3 biological replicates). L hMeDIP-qPCR assay of CK2B promoter in C643 cells with the indicated treatments (n = 3 biological replicates). M Co-IP assay showing interaction between HIF1α and p300 in C643 cells with the indicated treatments. ChIP-qPCR assay showing the binding of p300 to CK2B promoter in 8505C (N) and C643 (O) cells under hypoxia (n = 3 biological replicates). P A schematic model describing that TET1 promotes CK2B transcription as a coactivator of HIF1α by mediating p300-HIF1α interaction under hypoxia. For mRNA analysis, GAPDH was used as a reference gene. Dox− negative control, Dox+ cells inducibly expressing TET1, sgCon control cells, sgTET1 TET1-knockout C643 cells. siNC cells transfected with control siRNA, siHIF1A cells transfected with siRNA against HIF1α, Vector cells transfected with empty plasmid, HIF1A cells transfected with the plasmid expressing HIF1α. For ChIP-qPCR assays, graph shows enrichment folds of anti-HIF1α, anti-TET1, and anti-p300 relative to IgG. For hMeDIP-qPCR, graph shows the percentage of hydroxylmethylated DNA in genomic DNA. Histograms were shown in mean ± SD. Statistical analysis was performed by unpaired Student’s test. *p < 0.05, **p < 0.01, and ***p < 0.001.
