Fig. 5.

Methylation of TERT promoter sequences results in strong repression of heterologous reporter constructs. Reporter assays demonstrating that DNA methylation of the TERT promoter suppressed reporter expression in heterologous TERT promoter-reporter constructs. a Scheme of various deletion constructs of the TERT promoter driving luciferase expression. b HEK293T cells were transfected with deletion constructs of the TERT promoter driving luciferase expression with activity similar to a reporter construct driven by the GSTP1 promoter. The exceptions were deletion constructs lacking elements of the core promoter (Del 6 and Del 1). Methylation of reporters significantly inhibited expression in all constructs. c Nanoluc or d pCpGL reporters driven by mutant or wild type TERT promoter sequences show higher expression in mutant compared to wild type promoters, with activity largely abolished in methylated constructs independent of host cell mutation status