DNA Methylation Increases Nucleosome Compaction and Rigidity

摘要

DNA in eukaryotic cells is packaged into arrays of nucleosomes, each assembled from ～147 base pairs of DNA wrapped around a histone octamer and folded into higher-order chromatin structures. Enzyme-mediated chemical modifications of DNA and histones regulate various genome transactions by modulating access to the DNA. One example of these epigenetic modifications is methylation of CpG dinucleotides, which is often associated with gene repression. While CpG methylation is essential in development, inappropriate CpG methylation in tumor suppressor genes is associated with cancer. A better understanding of how CpG methylation affects nucleosome structure will provide insights into the mechanism of gene repression and the development of novel drugs to treat methyl-CpG-related diseases.