Transcriptionally Repressive Chromatin Remodelling and CpG Methylation in the Presence of Expanded CTG-Repeats at the DM1 Locus
Figure 4
Expanded CTG-repeats are associated with local chromatin remodelling towards a less active chromatin conformation around the CTG-repeat. Less occupancy of active histone marks H3K9/14Ac (H3KAc in graph) (a) and more repressive histone marks (H3K9Me3) (c) around CTCFbs1 and bs2 is observed upon CTG-repeat expansion, while enrichment of repressive mark H3K27Me3 (b) is unaffected. These graphs show enrichment (Qt(IP)/Qt(input), normalised against the abCHIP enrichment value of the positive control amplicon of each respective repeat length category) for different histone modifications in abChIP versus IgG-IP at three regions at the DM1 locus. Height of the bars indicates the median enrichment, and error bars indicate the interquartile range (25th to 75th percentile of observations). Mann-Whitney tests were performed to test for a statistically significant difference between the abChIP and IgG reactions. Results are summarised here with * being , ** being , and *** being . Details of the statistical analysis can be found in Supplementary Table 1. The enrichment values obtained for the specific abChIP reactions were subjected to the Jonckheere Terpstra test for trend, which tests whether a trend exists across the categories with increasing CTG-repeat length. values are indicated in the graphs and details of this statistical analysis can be found in Supplementary Table 2.
