(A) N2a cells stably expressing PrP or Opn-PrP were treated for 0–8 hr with 10 mM DTT and analyzed for total PrP by immunoblot. Note the increased accumulation of the ER form in Opn-PrP cells relative to PrP cells, especially obvious at the 4 hr time point.
(B) Cells stably expressing PrP or Opn-PrP were treated with 10 mM DTT for 24 hr, replated in normal media, and visualized 10 days later by staining with crystal violet.
(C) Cells stably expressing PrP or Opn-PrP were treated for 0–8 hr with 5 µM MG132 and analyzed for total PrP by immunoblot. Note the increased accumulation of unglycosylated species (−CHO) for PrP, but not for Opn-PrP.
(D) Cells treated with 5 µM MG132 for 24 hr were replated in normal media and visualized 8 days later by staining with crystal violet.
(E) Quantification of replating viability assays for survival of cells expressing PrP (gray bars) or Opn-PrP (black bars) after the indicated treatments for 24 hr (5 µM MG132), 6 hr (10 mM DTT), 18 hr (1 µg/ml Tunicamycin; Tm) or 5 min (5 µM Tg).