Analysis of ZIP (Zrt-, Irt-related protein) transporter gene expression in murine neural stem/progenitor cells.

Zinc plays important roles for brain development. Zrt-, Irt-related protein (ZIP) is a major transporter family to regulate the intracellular zinc levels. Neural stem/progenitor cells (NSPCs) are more sensitive than their differentiated progeny (neural/glial cells) to zinc in vitro (Nishikawa et al., 2015). We analyzed relative gene expression of 14 different ZIPs in murine NSPCs and differentiated cells by real-time polymerase chain reaction technique. Expression of Zip4 and that of Zip12 drastically increased, while that of Zip8 clearly decreased after differentiation of NSPCs. Downregulation of NSPC's marker (Nes) and upregulation of differentiated cell markers (Tubb3; neuron, Gfap; astrocyte) occurred simultaneously. ZIP8 protein was immunochemically detected both in cultured neurospheres consisting of NSPCs in vitro and in subventricular zone of embryonic mouse brain in vivo, like a novel surface marker of NSPCs. We considered that required types of ZIP changed during the differetiation of NSPCs.