Trafficking and intracellular ATPase activity of human ecto-nucleotidase NTPDase3 and the effect of ER-targeted NTPDase3 on protein folding

The human ecto-nucleoside triphosphate diphosphohydrolases (NTPDase3) in COS-1 cells was expressed to block the secretory transport with monensin or brefeldin A, or by targeting to endoplasmic reticulum (ER) with signal peptide to study the subcellular location and the mechanism of ecto-nucleotidase activation. The findings from ER-targeted NTPDase3 could be applied as an experimental tool to study the effects of ER ATP depletion on ER function under normal and stress conditions.