A nice analysis of the trimethylation of histon 3 at lysine 4 (H3K4me3) appears in Cell this week (http://dx.doi.org/10.1016/j.cell.2014.06.027). Benayoun and Pollina et al. claim that this marker labels preferentially those proteins that are essential for the cell’s function. The marker has been found at the start of most transcribed genes, but Benayoun and Pollina argue that not its mere presence, but the intensity of its presence is a sign that this protein is relevant for lineage specifity. If this intensity is disturbed, that function is not maintained.
This is a metaanalysis of a very broad range including human, mammalian, protostomes, plants and fungi. Nicely done!