Altres ajuts: The authors thank Tom Yohannan for the editorial advice and the IBEC Nanotechnology Platform staff for their generous help. This research was supported by grants from CIBERNED (PI2014/02-4 (Rapid dementias), PRY-14-114 and PRY2016-02, La Caixa Obra Social Foundation and La Marató de TV3) to J.A.D.R. M.S.-F was supported by CIBERNED, A.H was supported by La Caixa Obra Social Foundation and L.U. was supported by a fellowship from the Marató TV3 foundation.

The cellular prion protein, encoded by the gene Prnp, has been reported to be a receptor of β-amyloid. Their interaction is mandatory for neurotoxic effects of βamyloid oligomers. In this study, we aimed to explore whether the cellular prion protein participates in the spreading of α-synuclein. Results demonstrate that Prnp expression is not mandatory for α-synuclein spreading. However, although the pathological spreading of αsynuclein can take place in the absence of Prnp, αsynuclein expanded faster in PrPC-overexpressing mice.