ZnT-1 enhances the activity and surface expression of T-type calcium channels through activation of Ras-ERK signaling Academic Article uri icon

abstract

  • Zinc transporter-1 (ZnT-1) is a putative zinc transporter that confers cellular resistance from zinc toxicity. In addition, ZnT-1 has important regulatory functions, including inhibition of L- type calcium channels and activation of Raf-1 kinase. Here we studied the effects of ZnT-1 on the expression and function of T-type calcium channels. In Xenopus oocytes expressing voltage-gated calcium channel (CaV) 3.1 or CaV3. 2, ZnT-1 enhanced the low-threshold calcium currents (I caT) to 182±15 and 167.95±9.27% of control, respectively (P< 0.005 for both channels). As expected, ZnT-1 also enhanced ERK phosphorylation. Coexpression of ZnT-1 and nonactive Raf-1 blocked the ZnT-1-mediated ERK phosphorylation and abolished the ZnT-1-induced augmentation of I caT. In mammalian cells (Chinese hamster ovary), coexpression of CaV3. 1 and ZnT-1 increased the I caT to 166.37±6.37 …

publication date

  • January 1, 2012