Reprogramming the epigenome: erasing memory and creating diversity (360G-Wellcome-210754_Z_18_Z)
Epigenetic memory needs to be globally reprogrammed in the early mammalian embryo for cells to attain broad developmental potency including naïve pluripotency. Exit from pluripotency in turn requires rapid establishment of epigenetic memory in the form of epigenetic priming. This involves both ‘activating priming’ whereby lineage specific genes are protected from repressive marking to safeguard their future transcriptional activation during tissue and organ development, and ‘repressive priming’ by which genes of a different lineage are suppressed. These large-scale dynamics raise fundamental questions about the impact of epigenetic memory on pluripotency and differentiation, which we address in this research programme. First, we will attempt to disable global demethylation in vitro and in vivo by manipulating the epigenetic coordinator UHRF1 at the transcriptional and posttranscriptional levels. Second, using genetic and epigenetic manipulation we will determine the mechanisms and downstream consequences on lineage and tissue development of ‘activating priming’ factors we have recently identified. Third, we will investigate the role and targets of ‘repressive priming’ and epigenetic heterogeneity in cell fate decisions and lineage development. New insights gained into memory erasure and epigenetic determinants of cell fate will illuminate and guide strategies for using ES, iPS, and multipotent stem cells in regenerative medicine.
£2,634,297 10 Apr 2018