Zinc transporter 9

Intracellular zinc homeostasis is regulated by zinc-binding proteins and zinc transporters (Rink et al. 2007). The zinc transporters are encoded by two SLC ("solute linked carrier") gene families:

• Members of the SLC39 family (Zip, "Zrt- and Irt-like proteins") increase the cytoplasmic zinc level by zinc uptake.
• Members of the SLC30 family (ZnT, zinc transporter/exporter; CDF family, cation diffusion facilitator) lower intracellular zinc concentrations by transporting zinc out of the cell or into vesicular structures.

To date, 15 Zips and 9 ZnTs have been detected in various human cells.ZnT-9 is also known as HUEL and shows a widespread expression (Cousins 2004). There is no information about regulatory mechanisms.

1. Chausmer AB (1998) Zinc, insulin and diabetes. J Am Coll Nutr 17: 109-115.
2. Chimienti F et al (2005) ZnT-8, a pancreatic beta-cell-specific zinc transporter. Biometals 18: 313-317.
3. Chowanadisai W et al (2006) Identification of a mutation in SLC30A2 (ZnT-2) in women with low milk zinc concentration that results in transient neonatal zinc deficiency. J Biol Chem 281: 39699-39707.
4. Cousins RJ et al (2003) A global view of the selectivity of zinc deprivation and excess on genes expressed in human THP-1 mononuclear cells. Proc Natl Acad Sci USA 100: 6952-6957.
5. Overbeck S (2008) The regulation of zinc transporters and their influence on intracellular zinc homeostasis in leukocytes. Dissertation. Publication server of RWTH Aachen University
6. Rink L et al (2001) Extracellular and immunological actions of zinc. Biometals 14: 367-383.
7. Rink L et al (2007) Zinc homeostasis and immunity. Trends Immunol 28: 1-4.