Fig. S8.

Alignment of the amino acid sequences of mouse XK and Xkr8. The amino acid sequences of human (h) and mouse (m) XK and Xkr8 were aligned to obtain the maximal homology by introducing gaps (–). The amino acid residues that are identical among the four members are in bold red, and the residues that are conserved only between human and mouse Xkr8 are in light red. The putative transmembrane regions are shadowed in gray, and the extracellular regions are in light green. The cysteine residues at position 347 of XK connected with Kell are highlighted in blue.