Why are prion diseases precluded by non-mammals?

摘要

Prion diseases (PDs), also known as transmissible spongiform encephalopathies, are a severe threat to the world today – they not only spread within animals but also infect humans, and there is no effective therapeutic approach for them [1-4]. Although the pathogenic mechanisms of PDs are not clear, the induction of normal cellular prion protein (PrPC) into the abnormal scrapie isoform of the protein (PrPSc) constitutes the core of the etiology of PDs [1-4]. However, it remains elusive why PDs are concentrated in mammals but precluded by non-mammals, although prion genes are shared by vertebrates.