Microbial specialization by prions

Abstract

Microbial prions facilitate a variety of phenotypic switches. Recently-developed tools that can directly interrogate, in the living cell, the aggregation state of a protein have enabled a wider range of experiments for prion-mediated behaviors. With such tools, the roles of the yeast prion [SWI] in migration and mating were studied. Although [SWI] cells were consistently less fit than their [swi] counterparts under traditional laboratory conditions, in these new phenotypic paradigms [SWI] cells demonstrated a distinct advantage. [SWI] cells dispersed over a larger area under conditions resembling rainfall and outcrossed more frequently. We postulate that many behaviors in microorganisms may be modulated by stochastic prion switching. In diverse and changing natural environments, prion switching at low frequency may promote greater fitness of the population by specializing a small number of individuals with altered responses to their environments.

Aggregation and Prion-Inducing Properties of the G-Protein Gamma Subunit Ste18 are Regulated by Membrane Association

“…In yeast and fungi, prions control heritable traits. Some yeast prions are clearly deleterious to the host [ 2 , 3 ], while other have been linked to potentially adaptive roles [ 4 , 5 , 6 , 7 , 8 ]. Supposedly, formation of heritable aggregates increases phenotypic diversity by altering a range of cellular processes that may have various phenotypic consequences.…”