p53 protein may show a typical prion-like behavior when mutated
 

Prions, the causal agents of Mad Cow and other diseases, are very unique infectious particles. They are proteins in which the complex molecular three-dimensional folding process just went astray. For reasons not yet understood, the misfolding nature of prions is associated to their ability to sequester their normal counterparts and induce them to also adopt a misfolding conformation.

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