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Figure 1. Nhp6 or curaxins can initiate uncoiling of nucleosomal DNA to promote reorganization by FACT. Either Nhp6/HMGB or curaxins can weaken the histone: DNA contacts near the entry/exit points of the nucleosomal DNA, exposing the binding site in H2A-H2B dimers for the acidic/hydrophobic anchor sequences found in the C-terminal domains of both subunits of FACT^[1]. The DNA distortion initiates a stepwise series of binding events by different domains of FACT that ultimately leads to uncoiling of the DNA to make the reorganized form of the nucleosome. Each step is reversible, providing a pathway for assembly of nucleosomes. Structures of the domains of FACT are shown, with the HMGB domain of SSRP1 represented by Nhp6 (modified from Figure 8^[2] ). FACT: facilitates chromatin transcription; Nhp6: non-histone protein 6; HMGB: high mobility group B; Spt16: suppressor of ty 16; Pob3: polymerase one binding protein 3