FIG 4.

Proposed interaction of H1 and HMGB proteins with nucleosomes. (A) H1 binds near the dyad such that the CTD mainly contacts one linker segment; this creates a stem-like structure that stabilizes the nucleosome core (32, 38). (B) For HMGB, interactions between the acidic CTD and the H3 N-terminal tail that exits near the dyad promote binding of HMGB to DNA; the DNA bending and underwinding induced may propagate to the nucleosome core to promote unwrapping or access to other factors (118, 119).