Comparison of TRAIL-R2 structures.

<p>The TRAIL-R2 structure derived from the complex with UL141 (4I9X, in cyan) is superimposed (residues 78–178) with available TRAIL-R2 crystal structures from PDB database. Three TRAIL-R2–TRAIL structures: 1D4V (grey), 1DU3 (green) and 1D0G (light purple) and two TRAIL-R2–Fab structures: YSd1 Fab (1Z3A, red) and BdF1 Fab (2H9G, yellow). (<b>a</b>) Structures superimpose very well with the exception of the β1β2 loop of CRD-3 (Patch 3). Representative 2F_O-F_C electron density map contoured at 1σ, showing the key residues of receptor β1β2 loop (cyan) interacting with UL141 residues (orange) in patch 3 (<b>b</b>) and patch 3 U (<b>c</b>) in stereo views. The well-defined electron density indicates, that the β1β2 loop of CRD-3 is well ordered upon UL141 binding.