The emerging role of zinc transporters in cellular homeostasis and cancer

Zinc is an essential micronutrient that plays a role in the structural or enzymatic functions of many cellular proteins. Cellular zinc homeostasis involves the opposing action of two families of metal transporters: the ZnT (SLC30) family that functions to reduce cytoplasmic zinc concentrations and the ZIP (SLC39) family that functions to increase cytoplasmic zinc concentrations. Fluctuations in intracellular zinc levels mediated by these transporter families affect signaling pathways involved in normal cell development, growth, differentiation and death. Consequently, changes in zinc transporter localization and function resulting in zinc dyshomeostasis have pathophysiological effects. Zinc dyshomeostasis has been implicated in the progression of cancer. Here we review recent progress toward understanding the structural basis for zinc transport by ZnT and ZIP family proteins, as well as highlight the roles of zinc as a signaling molecule in physiological conditions and in various cancers. As zinc is emerging as an important signaling molecule in the development and progression of cancer, the ZnT and ZIP transporters that regulate cellular zinc homeostasis are promising candidates for targeted cancer therapy

Heterologous Expression of Full-Length and Truncated Human ZIP4 Zinc Transporter in Saccharomyces cerevisiae

The human (h) transporter hZIP4 is the primary Zn2+ importer in the intestine. hZIP4 is also expressed in a variety of organs such as the pancreas and brain. Dysfunction of hZIP4 can result in the Zn2+ deficiency disease acrodermatitis enteropathica (AE). AE can disrupt digestive and immune system homeostasis. A limited number of hZIP4 expression strategies have hindered increasing knowledge about this essential transmembrane protein. Here, we report the heterologous expression of hZIP4 in Saccharomyces cerevisiae. Both a wild-type and a mutant S. cerevisiae strain, in which the endogenous Zn2+ transporters were deleted, were used to test the expression and localization of an hZIP4–GFP fusion protein. A full-length hZIP4–GFP and a truncated membrane-domain-only (mhZIP4–GFP) protein were observed to be present in the plasma membrane in yeast

Monitoring Cooker Activities Using a Grid-EYE Infrared Array Sensor

One of the challenges of our ageing society is to create a safe environment in which the elderly can live. Although the idea of creating an entirely risk-free society is impossible, it is feasible to monitor the health of elderly people by placing smart sensors in their houses, in order to react as soon as possible if a hazardous situation is taking place. In particular, this project focuses on the kitchen environment, by monitoring daily cooking activities and detecting anomalies in the use of the cooker, using some low-cost sensors: a Grid-EYE and a Sharp sensor