Essentially clumps of misfolded proteins, prions cause neurodegenerative disorders, such as mad cow/Creutzfeld-Jakob disease, in humans and animals. Prions trigger the misfolding and aggregation of their properly folded protein counterparts, but they usually need some kind of "seed" to get started.
Biochemists at Emory University School of Medicine have identified a yeast protein called Lsb2 that can promote spontaneous prion formation. This unstable, short-lived protein is strongly induced by cellular stresses such as heat. Lsb2's properties also illustrate how cells have developed ways to control and regulate prion formation. Research in yeast has shown that sometimes, prions can actually help cells adapt to different conditions.
The results are published in the July 22 issue of the journal Molecular Cell. The senior author is Keith Wilkinson, PhD, professor of biochemistry at Emory University School of Medicine The first author is senior associate Tatiana Chernova, PhD.
The aggregated form of proteins connected with several other neurodegenerative diseases such as Alzheimer's, Parkinson's and Huntington's can, in some circumstances, act like prions. So the Emory team's finding provides insight into how the ways that cells deal with stress might lead to poisonous protein aggregation in human diseases.
"A direct human homolog of Lsb2 doesn't exist, but there may be a protein that performs the same function," Wilkinson says. "The mechanism may say more about other types of protein aggregates than about classical prions in humans, This mechanism of seeding and growth may be more important for aggregate formation in diseases such as Huntington's."
Lsb2 does not appear to form stable prions by itself. Rather, it seems to bind to and encourage the aggregation of another protein, Sup35, which does form prions.
"Our model is that stress induces high levels of Lsb2, which allows the accumulation of misfolded prion proteins," Wilkinson says. "Lsb2 protects enough of these newborn prion particles from the quality control machinery for a few of them to get out."
The research was supported by the National Institutes of Health.
T.A. Chernova et al. Prion Induction by the Short-lived Stress Induced Protein Lsb2 Is Regulated by Ubiquitination and Association with the Actin Cytoskeleton Mol. Cell (2011).
Holly Korschun | EurekAlert!
Link Discovered between Immune System, Brain Structure and Memory
26.04.2017 | Universität Basel
Researchers develop eco-friendly, 4-in-1 catalyst
25.04.2017 | Brown University
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
26.04.2017 | Life Sciences
26.04.2017 | Physics and Astronomy
26.04.2017 | Earth Sciences