Extended Data Fig. 8: Repositioning of the H4 N-terminal tail.
From: Nucleosome-bound SOX2 and SOX11 structures elucidate pioneer factor function
Related to Fig. 4. Cryo-EM maps are shown with a Gaussian smoothening filter (Chimera49) applied for clarity. SOX is coloured in pink, H4 is shown in green and the repositioned H4 tail is shown in orange. a, Free nucleosome. Views of SHL +2 and SHL −2 are shown to illustrate the position of the H4 tail (a dashed line). Residue K16 is marked with a circle. b, Nucleosome–SOX11 with SOX11 located at SHL +2. On the right, a superimposition with the free nucleosome map is shown to highlight different orientations of the H4 tail. c, Nucleosome–SOX11 complex with SOX11 located at SHL −2. In this ___location, SOX is oriented differently and does not clash with or reposition the H4 tail. d, Nucleosome–SOX11*. The H4 N-terminal tail is repositioned compared with that in the free nucleosome. Repositioning of the H4 tail was reported in case of strong distortions in the nucleosome structure30. e, SOX binding repositions the H4 N-terminal tail and might impair nucleosome stacking. Side view of two stacking nucleosomes (from PDB code 1AOI). H4 interacts with the acidic patch on the neighbouring H2A–H2B histone dimer. H4 tail repositioning is incompatible with nucleosome stacking.
