A bacterial global regulator forms a prion

Abstract

Prions enter another domain of life Prions are self-propagating protein aggregates, discovered in connection with the fatal transmissible spongiform encephalopathies in mammals. Prions have also been identified in fungi, where they act as protein-based elements of inheritance. Although prions have been uncovered in evolutionarily diverse eukaryotic species, it is not known whether prions exist in bacteria. Yuan and Hochschild report the identification of a bacterial protein—the transcription termination factor Rho from Clostridium botulinum —that exhibits the defining hallmarks of a prion-forming protein. Science , this issue p. 198