Epigenomic profiling in maize inbred lines and their reciprocal hybrids. (a) Distribution of DNA methylation, H3K4me3 and H3K9ac levels around transcription start site (TSS) and transcription termination site (TTS) of differentially expressed genes. Genes with detected transcripts were sorted according to their expression levels, and further divided into three groups (high, medium, and low expression levels, each with an equal number of genes). The mean read coverage of genes with epigenetic modifications was plotted (y-axis). (b) Frequencies of epigenetically modified regions in genic and intergenic regions of the maize genome. For each epigenetic mark, modified genomic regions identified using merged sequencing data from shoots and roots of both hybrids and parents were included in the analysis. (c) Number and percentage of genes identified with expression or epigenetic modifications. For each organ, only genes with detected transcripts or epigenetic modifications in both hybrids and parents were included.
He et al. Genome Biology 2013 14:R57 doi:10.1186/gb-2013-14-6-r57