The observation that pharmacological inhibition of the proteasome led to accumulation of an unglycosylated PrP species in neuroblastoma N2a cells [8], [9] was interpreted as evidence that part of the newly synthesized PrP was constitutively recognized as misfolded by the ER quality control and diverted to the ER-associated degradation (ERAD) pathway, which implies retrograde transport from the ER lumen to the cytosol, deglycosylation by cytosolic N-glycanases, and proteasomal degradation [10]. The gene discussed is PRNP; the disease is neuroblastoma.