The shape of things to come: structural insights into how prion proteins encipher heritable information.

The prion hypothesis embodies the radical concept that prion proteins contain the necessary information for infectious replication within their shape, thus obviating the requirement for genomic material. Two elegant papers by Hoyt et al. and Manka et al. describing high-resolution structures of infectious prions bring us closer to answering the long-standing question of how different prion conformations produce heritably distinct diseases.