Genome-wide analysis of chromatin states of Ectocarpus sporophytes and gametophytes, experiment 2

The aim of this study was to analyze genome-wide patterns of histone post-translational modifications (PTMs) and nucleosome distribution during the sporophyte and gametophyte generations of the life cycle of the brown alga Ectocarpus. Analysis of the results of this experiment along with those generated by a second experiment “Genome-wide analysis of chromatin states of Ectocarpus sporophytes and gametophytes, experiment 1” indicated that the histone PTMs H3K4me2, H3K4me3, H3K9ac, H3K14ac and H3K27ac are associated with the transcriptional start sites (TSSs) of actively expressed genes, H3K36me3 preferentially marks gene bodies and is associated with gene activation, H4K20me3 marks transposons and is associated with gene repression, probably through the silencing of transposons in introns. H3K79me2 occurs in zones corresponding to about a third of the genome. These zones often span several genes and genes within H3K79me2 zones exhibit lower levels of transcript abundance. Overall design: Analysis of six histone post-translational modifications, along with MNase-seq, H2AZ and RNA-seq analyses, during the two generations (sporophyte and gametophyte) of the life cycle of the brown alga Ectocarpus, using duplicate samples for each generation.