Incurable infectious neurodegenerative diseases, such as """"""""mad cow"""""""" disease and human Creutzefeldt-Jacob disease, are postulated to be transmitted by an abnormal aggregation-prone protein isoform (prion). Prion aggregates are believed to be capable of seeding aggregation of the normal cellular protein, converting it into a prion. Pathology of prion diseases is reminiscent of other protein assembly disorders (such as Alzheimer?s disease) associated with amyloid-like aggregation. In yeast, prions control phenotypic traits inherited via cytoplasm. This provides a molecular basis for protein-based inheritance. As several unrelated proteins exhibit prion-forming potential, it is likely that protein-based inheritance may play an important biological role. The power of yeast genetic analysis makes yeast a useful model for studying general mechanisms of prion propagation. While many proteins can form amyloid-like aggregates in vitro, only some of them are capable of transmitting the aggregated state in vivo. This means that cells are normally able to prevent aggregate propagation. However, prions are overcoming the cellular defense systems. Moreover, our research has proven that the cellular stress-defense machinery becomes an essential component of prion propagation in the yeast cell. The overall, goal of this proposal is to uncover mechanisms by which cellular systems control prion formation and propagation in the yeast cell. This will explain how environmental and physiological factors induce protein-based inheritable variations, and may provide a new tool for curing aggregation-based disorders by altering the cellular regulatory systems. Proteins affecting prion formation and propagation in yeast will be investigated: stress-related chaperones of the evolutionary conserved Hsp100 and Hsp70 groups; ubiquitin system, normally involved in targeting misfolded proteins for degradation; and cytoskeletal assembly proteins involved in formation of cortical actin patches and endocytic vesicles.
Specific Aims of the proposal are as follows: 1) To study a mechanism of prion regulation by the heat shock protein balance. 2) To study the role of ubiquitin system in the cellular control of yeast prions. 3) To study interactions between prions and cytoskeleton-associated structures in yeast.
Gong, He; Romanova, Nina V; Allen, Kim D et al. (2012) Polyglutamine toxicity is controlled by prion composition and gene dosage in yeast. PLoS Genet 8:e1002634 |
Antony, H; Wiegmans, A P; Wei, M Q et al. (2012) Potential roles for prions and protein-only inheritance in cancer. Cancer Metastasis Rev 31:1-19 |
Kiktev, Denis A; Patterson, Jesse C; Muller, Susanne et al. (2012) Regulation of chaperone effects on a yeast prion by cochaperone Sgt2. Mol Cell Biol 32:4960-70 |
Liebman, Susan W; Chernoff, Yury O (2012) Prions in yeast. Genetics 191:1041-72 |
Chernova, Tatiana A; Romanyuk, Andrey V; Karpova, Tatiana S et al. (2011) Prion induction by the short-lived, stress-induced protein Lsb2 is regulated by ubiquitination and association with the actin cytoskeleton. Mol Cell 43:242-52 |
Newnam, Gary P; Birchmore, Jennifer L; Chernoff, Yury O (2011) Destabilization and recovery of a yeast prion after mild heat shock. J Mol Biol 408:432-48 |
Kiktev, D A; Chernoff, Y O; Archipenko, A V et al. (2011) Identification of genes influencing synthetic lethality of genetic and epigenetic alterations in translation termination factors in yeast. Dokl Biochem Biophys 438:117-9 |
Chen, Buxin; Bruce, Kathryn L; Newnam, Gary P et al. (2010) Genetic and epigenetic control of the efficiency and fidelity of cross-species prion transmission. Mol Microbiol 76:1483-99 |
Goehler, Heike; Droge, Anja; Lurz, Rudi et al. (2010) Pathogenic polyglutamine tracts are potent inducers of spontaneous Sup35 and Rnq1 amyloidogenesis. PLoS One 5:e9642 |
Romanova, Nina V; Chernoff, Yury O (2009) Hsp104 and prion propagation. Protein Pept Lett 16:598-605 |
Showing the most recent 10 out of 36 publications