Tissue- and cell type-specific modification of prion protein (PrP)-like protein Doppel, which affects PrP endoproteolysis

► Differently modified Doppel proteins were expressed according to cell types and tissues. ► The level of endoproteolytic fragment of PrP was reduced by the Doppel expression in a transfected PrP gene-deficient neuronal cell line with both PrP and Doppel. ► The functional interactions between PrP and Doppel affected PrP endoproteolysis.