Epigenetic editing to unravel the causal function of Marks of Active Chromatin: a quantitative and mechanistic dissection

ongoing

Chromatin modifications are essential for the transcriptional programmes underpinning development and cellular identity. However, an understanding of the causal function(s) of chromatin marks in gene regulation has lagged behind. Particularly, whether chromatin modifications linked with active transcription (active marks) have a causal function remains intensely debated, while the underlying mechanisms are poorly understood. This is due to technical limitations in the ability to precisely perturb chromatin marks in a locus-targeted manner. In this project, I will leverage cutting-edge (epi)genomic tools to systematically dissect the causal roles of key active chromatin marks—H3K4me3, H3/H4ac, and H3K79me2—, at a mechanistic and quantitative level. To directly link locus-specific active mark deposition to transcriptional responses, I will employ a novel epigenome editing technology that allows precise and targeted deposition of chromatin marks. By combining this advanced tool with unbiased genome-wide CRISPR screens using the orthogonal enCas12a system, I will systematically uncover the molecular mechanisms that decode the function of active marks. Additionally, I will dissect the quantitative effects of these marks on transcription at the single-cell level using a tunable epigenetic editing platform. If successful, this proposal will provide unprecedented mechanistic insights into the role of active chromatin marks, paving the way to new therapeutic strategies that harness precise epigenetic control of gene expression.