PRNP and Creutzfeldt Jacob disease: To determine if the loss of anti-Bax function from the GSS-associated PrP mutants is due to lower levels of CyPrP as previously shown in CJD mutants [31], transfected cells treated with Brefeldin A to promote retrotranslocation and epoxomicin to prevent proteasomal degradation of CyPrP, were submitted to subcellular fractionation (Fig. 3A).