Once again, sequence similarity between PrPC and PrPSc was not the driving force for this observation since higher levels of PrPres were observed in cells expressing E227D/S230R-mutant BVPrP following infection with BVPrP-adapted RML and 22L prions compared to wild-type BVPrP-expressing cells (Fig 5I). Here, PRNP is linked to infection.