ZIP6 (SLC39A6) is a zinc (Zn) transporter located on the cell membrane.

Zn is an essential heavy metal, part of numerous biological processes as an enzymatic co-factor, and also as an intracellular signaling mediator that recruits extracellular stimuli and determines the final outputs of various physiological pathways. Intracellular and extracellular Zn levels regulate many cellular processes such as autophagy, cell growth and death, and cell migration^1,2.

Movement of Zn in and out of cells, across membranes, is regulated by zinc transporters. Zn transporter protein 6 (ZIP6) is a member of the ZIP family of Zinc transporters and of the LIV-1 sub-family. ZIP transporters contain 8 transmembrane domains with a cytoplasmic region between TM3 and TM4. LIV-1 subfamily members contain the HEXXH motif within TM5. They also exhibit diverse lengths of the N-terminal extracellular domain³.

The gene encoding this transporter has been shown to take part in estrogen receptor‐positive breast cancer and serves as a reliable marker of this disease. Overexpression of ZIP6 protein is also observed in prostate and kidney tumor cells⁴.

ZIP6 is also strongly upregulated during T-cell activation⁵. ZIP6 heteromerizes with ZIP10 for oocyte-to-egg transition and epithelial to mesenchymal transition in fetus development^6,7.