Fig. 1
The two FAT10 UBDs are structurally independent in solution. a Schematic representation of the FAT10 NMR constructs and domain boundaries. Ubiquitin-like domain (UBD)_N and UBD_C denote the boundaries of the N- and C-terminal ubiquitin-like (UBL) folds, respectively. b Representative region of the 1H,15N-correlation spectrum of Cys-free full-length human FAT10 (FAT10 C0) and c an overlay of the 1H,15N-correlation spectra of the Cys-free FAT10 lacking the N-terminal four amino acids (ΔN FAT10) with the isolated Cys-free FAT10 N- (red) and C- (cyan) domains, respectively. Except for E86 at the C-terminus of the N-domain and the N-terminus of the C-domain, the spectra of the isolated domains are highly similar to the ΔN FAT10 construct demonstrating the structural independence of the domains. d Ribbon representation of the crystal structure of the FAT10 N-domain. Secondary structure elements are labeled to highlight the canonical ββαββαβ β-grasp fold. e Ribbon representation of the lowest energy NMR structure of the FAT10 C-domain. f Overlay of the structures of the FAT10 N- and C-domain (salmon and cyan, respectively) with Ub (PDB ID: 1UBQ) (gray). The structures superimpose with Ub with an r.m.s.d. for all backbone atoms of 0.764 Å for the N-domain (amino acids 8–81) and 0.964 Å for the C-domain (amino acids 88–160)
