Fig. 3.

XLRS-related mutations in the subunit interface and the corresponding positions in the sequence. The interface between adjacent subunits within an octameric ring (as seen from center) is composed of a long loop on the left subunit (red) and mainly the β-sheet face on the right subunit (blue) composed of residues 137, 139, 183–187, and 215. The interface loop (160–173) on the left are likely stabilized by the “sandwich” W122-R200-W163, and the interaction of Y166 with the 192–195 loop. A potential salt bridge can be formed between K167 and either E72 or E215. In the domain scheme at the bottom, the sequence locations of the subunit interfaces in the DS domain are shown in pink (those at the top are for the right side and those at the bottom for the left side). Residues potentially involved in the octamer ring connections are shown in dark blue.