Fig. 4. XPA rigging interlaces XPF/ERCC1 with DNA, XPD, XPB, and RPA at the 5′ junction and is key for licensing the XPF incision.

a View of XPA within the PInC assembly. XPA is depicted in cartoon representations and colored in tan. b Zoomed-in view highlighting of the interface of XPA’s β-domain and p8. TFIIH’s p8, p52, and XPB subunits are shown in surface representation. A schematic of XPA’s sequence colored by domain is shown above. c XPA interacting with DNA at the 5′ junction. XPA is colored by domains. The intercalating hairpin is shown in green and labeled. d Detailed residue interactions between the glycine-rich loop of XPA and the V-shaped groove of ERCC1. Residues are depicted in ball and stick representation and colored in purple and magenta.