Zinc transporters are membrane proteins that regulate the movement of Zn²⁺ ions across cellular membranes. They are essential for zinc homeostasis and are involved in numerous physiological processes.
There are two main families of zinc transporters:
1. ZIP (Zrt-, Irt-like Protein) Family – SLC39A family Function: Increase intracellular zinc by importing it into the cytosol from either outside the cell or from intracellular stores.
Examples: ZIP1, ZIP4, ZIP8, etc.
Clinical relevance:
ZIP4 mutations cause acrodermatitis enteropathica, a rare genetic disorder characterized by zinc deficiency.
2. ZnT (Zinc Transporter) Family – SLC30A family Function: Decrease cytosolic zinc by exporting it out of the cytosol to the extracellular space or into organelles (e.g., Golgi, endosomes).
Examples: ZnT1, ZnT3, ZnT5, ZnT8, etc.
Clinical relevance:
ZnT8 is associated with type 1 and type 2 diabetes – autoantibodies against ZnT8 are biomarkers in type 1 diabetes.
Why They Matter Zinc imbalance is linked to neurodegeneration, cancer, immune dysfunction, and metabolic diseases.
Zinc transporters are being studied as potential therapeutic targets and biomarkers.