Prions are self-propagating protein aggregates that can be transmitted between cells. The aggregates are associated with human diseases. Indeed, pathological prions cause mad cow disease and, in humans, Creutzfeldt-Jakob disease. The aggregation of prion-like proteins is also associated with neurodegeneration as in amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig’s disease. The regions within prion-like proteins that are responsible for their aggregation have been termed prion-like domains. Despite the important role of prion-like domains in human diseases, a physiological function has remained enigmatic. Researchers at the Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), the Biotechnology Center of the TU Dresden (BIOTEC), and Washington University in St. Louis, USA have now identified, for the first time, a benign, albeit biologically relevant, function of prion domains as protein-specific stress sensors that allow cells to adapt to and survive environmental stresses. Uncovering the physiological function is an essential first step towards closing a gap in understanding the biological role of prion-like domains and their transformation into a pathological disease-causing state. The discoveries were published in the January 5, 2018 issue of Science. The article is titled “Phase Separation of a Yeast Prion Protein Promotes Cellular Fitness.” The aggregation of prion-like proteins is associated with human diseases. Their infectious behavior is comparable to the spread of a viral infection. This raises the question of why evolution has kept these proteins around: are these sequences good for anything?
Login Or Register To Read Full Story