Fig. 4. APLFAD aromatic anchor residues are required for histone octamer assembly and chaperone activity in vitro.
(A) ITC binding curves and derived affinities (KD) of APLFAD wild-type (WT), the truncation mutant used for crystallization (APLFAD-Δ = Δ), or the double (Y462A/F468A = DA-34; Y476A/W485A = DA-AB) and quadruple (Y462A/F468A/Y476A/W485A = QA) mutants titrated to octamer-mix. (B) Percentage of octamer-compatible and octamer-incompatible histone-histone lysine cross-links based on surface-accessible Cα-Cα distances in the nucleosomal structure (Protein Data Bank: 2PYO) identified by XL-MS.