Figure 2.

Topological model of the Arabidopsis Na⁺/H⁺ exchanger AtNHX1, showing 12 transmembrane domains, and with a hydrophobic, luminal N-terminal and a hydrophilic, cytosolic C-terminal. The model was constructed and adapted according to the work of Sato and co-workers.⁸⁵ The darker transmembrane domains represent the predicted active site.⁸⁴