Chromatin profile comparison of expression-matched genes with and without CpG islands in their promoters. (a) Expression levels of 1,500 expression-matched CpG and non-CpG promoter genes classified as having low, medium and high expression levels (500 genes of each type in each category). (b) Average H3K36me3 profile between 500 bp upstream and 3 kb downstream of the transcription start site (TSS) of genes with or without a CpG promoter and with low, medium or high expression levels (color coded as in panel (a). Lines represent the loess-smoothed average read density shifted by 75 bp to indicate the position of the nucleosome dyad and the grey shading indicates the area within two standard errors of the predicted loess line.
Vavouri and Lehner Genome Biology 2012 13:R110 doi:10.1186/gb-2012-13-11-r110