Figure 1

Histone cores and tails. Here, we indicate the inner ends of the histones, amino- and carboxy-terminal tails, which lie a few amino acids towards the core domain from the indicated trypsin cleavage sites (black arrows), using the amino-acid numbering from yeast. Note that this criterion minimizes tail size slightly, as some modifications and some partially extended or flexible structure is found internal to these sites (within the 'globular' domains). Potentially charged residues and target sites of modification are indicated with bars (green for a lysine that is only known as an acetylation target; blue for a lysine that can be either acetylated or methylated; black for a lysine that can be ubiquinated; red for a phosphorylatable serine or threonine; yellow, a histidine that can be phosphorylated). Modified arginines and potential acceptors of ADP-ribose, Sumo and/or ubiquitin are not indicated.