Synthetic transcription factor overrides persistent repressive chromatin marks [ChIP-seq]

Methylation of lysine-9 residue of histone H3 (H3K9me3) is implicated in transcriptional silencing through chromatin condensation by its reader HP-1 proteins. Erosion, erasure and subsequent replacement of H3K9me3 by active acetyl-lysine marks accompanies transcriptional up-regulation.

Here, we report that a synthetic transcription elongation factor (SynTEF1), selectively targets the disease-causing GAA repeat expansion in frataxin and stimulates gene expression without erasure of the signature repressive marks or removal of HP1 proteins. Added epigenetic perturbation with a pharmacological agent leads to supra-synergistic frataxin expression that is unexpectedly accompanied by a dramatic rise in H3K9me3 levels.