Richard Meehan
University of Edinburgh, Scotland
Title: The formation of unmethylated chromatin compaction domains in embryonic stem cells and early development
Biography
Biography: Richard Meehan
Abstract
The complex chromatin environment of a single nucleus is a combinatorial outcome of a cells developmental history and the dynamic interplay between competing DNA and histone modifi cation pathways that act to reinforce stable
transcriptional states. Cell potency is initially established by signalling pathways and activation of pluripotent Gene Regulatory Networks (GRNs) in early embryogenesis; as development proceeds there is a programmed restriction in cell
fate choices that coincides with the establishment of and dependence upon repressive epigenetic silencing mechanisms. Our work suggests that two mutually exclusive repression pathways DNA methylation and polycomb, impacts on their
respective deposition in stem cell models. We fi nd that DNA methylation directs the formation of polycomb dependent higher order chromatin structure in stem cells and early development, conversely polycomb can direct patterns of DNA
methylation at discrete genomic regions. Author will discuss the impact of these mechanisms on stem cell potency and how these interactions are linked with the occurrence of altered epigenetic states in disease.