Cystathionine‐
‐synthase (CBS)‐pair domain divalent metal cation transport mediators (CNNMs) are an evolutionarily conserved family of magnesium transporters. They mediate magnesium homeostasis directly by transport of Mg
2+ ions and indirectly by regulation of the transient receptor potential ion channel subfamily M member 7 (TRPM7). Here, we report the crystal structure of the extracellular...