PRNP and prion disease: From a PMCA substrate containing only recombinant mouse PrP, RNA and POPG (1-Palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol), these synthetic prions were able to induce prion disease in a wild-type model, showing incubation periods similar to those obtained with classical prion strains and dispelling any doubts about the proteinaceous nature of the prion agent [32].