Zinc uptake transporter, ZIP1, belongs to the SLC39 transporter family. This transport has the ability to increase zinc concentration when cellular zinc level is low, by active zinc transport into the cytoplasm from extracellular space of the cell or the intracellular storage compartment. Thus, zinc transport plays a crucial role in regulating cellular zinc homeostasis^1-3.

Regulation and maintenance of proper concentration and distribution of cellular zinc are essential to the function, metabolism, growth, proliferation and survival of cells. Zinc deficiency can cause defects in the immune system, including abnormalities in T-cells, natural killer cells and monocytes, and reduction in antibody formation^1,2.

In the human genome, 20 ZIP transporters have been identified.  ZIP1 is encoded by the SLC39A1 gene³.

ZIP proteins are highly conserved. Members have eight predicted transmembrane (TM) domains with extracellular N- and C-termini. There is a long loop region harboring a histidine-rich domain between TM3 and TM4. Zinc uptake by ZIP1 is energy independent².

ZIP1 is ubiquitously expressed in human tissues including blood, brain, gill, heart, intestine, liver, muscle, skin, spleen and kidney³.

Accumulation of zinc in prostate cells by ZIP1 inhibits their growth and proliferation. Therefore, ZIP1 is associated as a tumor suppressor gene in prostate cancer².