Broad modifications of various positions of the minimal natural epitope recognized by the myelin-associated glycoprotein (MAG), a blocker of regeneration of neurite injuries, produced sialosides with nanomolar affinities.
We use the term "broad modification" to denote long regions of chromosomal space in which there is a given epigenetic modification present continuously (>50 kb), as opposed to focal regions of modification ("peaks") in a promoter or other region.
Unfortunately, this array format only covers a portion of the genome, hence, it will be necessary to use other methods, most likely ChIP-seq, to fully establish the prevalence of differences in broad modifications for this mark across different cell types.
We verified that a change in a broad modification affected gene expression of CACNG7.
We surveyed various epigenetic phenomena, including focal peaks, areas of broad modification, and bivalent promoters.
We establish the transcriptional relevance of a difference in an H3K9me3+ broad modification in that it affected transcription of CACNG7.
We detected differences among cell types in broad modification regions for H3K27me3 in many of the more lengthy regions that were tiled in this array format.
We found that "broad modifications", large areas of genomic space possessing an epigenetic mark (operationally defined as peaks >50 kb), also showed marked differences in presence or extent among cell types.
Overall, our "core set" data establishes sets of potential therapeutic targets, but the diversity in sets of sites and broad modifications among cell types underscores the need to carefully consider BTSC subtype variation in epigenetic therapy.
In contrast, clear changes in broad modifications were much less prevalent for H3K9me3 (4 of 44) and were absent for meC and H3K4me3 (0 of 44 in each case).
