Fig. 1.

ZnT8 topology and structural models based on YiiP, a bacterial homolog. (A) Topology model of ZnT8 indicating positions of the R325W SNP, zinc-sensing His-rich loop (IL2), and pair of His (H) and Asp (D) residues in TM 2 and 5 that are conserved in mammalian ZnT proteins. Also shown are the 49 amino-terminal and ~12 carboxy-terminal residues not found in YiiP. (B) Homology model of ZnT8 showing identical residues in YiiP (red), conserved substitutions (dark orange), extended N- and C-termini of ZnT8 (light blue), and zinc atoms observed in YiiP (dark blue spheres). (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)