Fig. 7.

a An X-ray crystal structure of a nucleosome (PDB ID: 1KX5). The nucleosome is composed of 147 base pairs of DNA (orange) wrapped around a histone octamer, which is composed of two copies of H3 (blue), H4 (red), H2A (green), and H2B (yellow) histone proteins. b Locations of histone tails in the nucleosome. Although crystal structures of the nucleosome core region (gray) have already been determined, the N-terminal regions (histone tails, red) of the histone proteins have not yet been determined due to their inate structural flexibility. The histone tail conformations in 1KX5 are modeled ones. In the applied research of ALSD, conformational sampling of an H3 histone tail was performed