ZnT 1

An abundantly expressed Zinc-transporter involved in the efflux of Zn²⁺

General Information

The essential micronutrient Zn plays an important role in many biological processes like growth, development and reproduction. It is found in the active site of many enzymes, where ionization, polarization or replacement of Zn²⁺ bound water is involved in catalytic reactions. As a charged ion Zn²⁺ cannot cross biological membranes by simple diffusion and must be transported by specialized transport mechanisms.
Four Zn transporter proteins ZnT 1, 2, 3 and 4 have been cloned. All of them contain several transmembrane domains and a histidine rich intracellular loop.
ZnT 1 is abundantly expressed and has been suggested to be responsible for the efflux of Zn²⁺ from cells. It is upregulated by high oral Zn doses.