Regulation of polycomb repressive complexes at the neural differentiation gene Pax6
type: CreativeWork
description: During body axis elongation spinal cord neural tissue in the posterior of the embryo is progressively generated from a pool of bipotent progenitors of the stem zone/caudal lateral epiblast, termed neuromesodermal progenitors. Neural differentiation gene transcription begins in a sharply defined position due to loss of fibroblast growth factor (FGF) signalling. This highly coordinated onset of gene expression implies the involvement of a higher order mechanism to co-ordinately regulate hundreds of genes at the same time. One possible mechanism underlying this phenomenon is the regulation of chromatin structure around neural differentiation genes. The analysis of chromatin structure by fluorescence in situ hybridisation uncovered that chromatin compaction at the neural differentiation gene Pax6 is maintained by FGF signalling in the stem zone/caudal lateral epiblast of the mouse embryo (Patel et al., 2013). Here I show that this process is mediated by ERK signalling, with just one hour of ERK inhibition leading to a decompaction of the Pax6 locus in the mouse embryo. One way in which local chromatin compaction is regulated is by polycomb repressive complexes. They build a machinery that deposit the histone modifications H3K27me3 and H2AK119Ub at target genes and were shown to impose chromatin compaction. To test the possibility of FGF/ERK regulated polycomb mediated chromatin compaction at neural differentiation gene loci in the stem zone/ caudal lateral epiblast a chromatin immunoprecipitation (ChIP) experiment was performed for the histone modification H3K27me3. Preliminary data showed that the Pax6 transcription start site in the stem zone caudal lateral epiblast is marked by H3K27me3, comparable to the known unexpressed polycomb target HoxD11. This indicated the potential for polycomb mediated chromatin compaction at the Pax6 locus. A human embryonic stem (ES) cell based in vitro model for the generation of spinal cord neural progenitors used to analyse further wh…
abstract: During body axis elongation spinal cord neural tissue in the posterior of the embryo is progressively generated from a pool of bipotent progenitors of the stem zone/caudal lateral epiblast, termed neuromesodermal progenitors. Neural differentiation gene transcription begins in a sharply defined position due to loss of fibroblast growth factor (FGF) signalling. This highly coordinated onset of gene expression implies the involvement of a higher order mechanism to co-ordinately regulate hundreds of genes at the same time. One possible mechanism underlying this phenomenon is the regulation of chromatin structure around neural differentiation genes. The analysis of chromatin structure by fluorescence in situ hybridisation uncovered that chromatin compaction at the neural differentiation gene Pax6 is maintained by FGF signalling in the stem zone/caudal lateral epiblast of the mouse embryo (Patel et al., 2013). Here I show that this process is mediated by ERK signalling, with just one hour of ERK inhibition leading to a decompaction of the Pax6 locus in the mouse embryo. One way in which local chromatin compaction is regulated is by polycomb repressive complexes. They build a machinery that deposit the histone modifications H3K27me3 and H2AK119Ub at target genes and were shown to impose chromatin compaction. To test the possibility of FGF/ERK regulated polycomb mediated chromatin compaction at neural differentiation gene loci in the stem zone/ caudal lateral epiblast a chromatin immunoprecipitation (ChIP) experiment was performed for the histone modification H3K27me3. Preliminary data showed that the Pax6 transcription start site in the stem zone caudal lateral epiblast is marked by H3K27me3, comparable to the known unexpressed polycomb target HoxD11. This indicated the potential for polycomb mediated chromatin compaction at the Pax6 locus. A human embryonic stem (ES) cell based in vitro model for the generation of spinal cord neural progenitors used to analyse further wh…
author: Semprich, Claudia
language: eng
date published: 2016
date modified: 2026-07-24T02:08:26Z
provider: University of Dundee
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Dundee