The association of DNA methylation and nucleosome occupancy with AS. (a) The distribution of genomic CpG dinucleotides level (CG) around the splice sites of different types of AS events. (b) The distribution of DNA methylation level (mCG) around the splice sites of different types of AS events. In both a and b, a sliding window of 147 bp is used for generating the profile for the figure; the x-axis is the position relative to acceptor site (left) and donor site (right); the y-axis is the CG percentage for a and the methylation percentage for b. (c) The distribution of nucleosome occupancy around the splice sites of different types of AS events. In c, no sliding window is used (see Methods for details); the x-axis is as in a, and the y-axis represents the ChIP signal level. (ES (exon skipping), ME (mutually exclusive exon, A5SS (alternative 5' splice site selection) A3SS (alternative 3' splice site selection), IR (intron retention)).