Figure 1. Structural relationship of DrZIP1 and FrZIP1 with human SLC39A1 and SLC39A2.

The predicted DrZIP1 and FrZIP1 proteins were aligned with human SLC39A1 and SLC39A2. The eight predicted TM domains are underlined and numbered I–VIII. Shaded residues represent positions of identity or similarity among the sequences as compared with DrZIP1 and FrZIP1. Two potential histidine-rich metal binding motifs between TM III and TM IV are underlined in grey. The signature sequences are highlighted in grey. ▲, conserved histidine and serine residues; △, glutamate residues conserved between DrZIP1, FrZIP1, SLC39A1 and SLC39A2; ◇, potential phosphorylation sites of PKC.