Structural Determinants in Prion Protein Folding and Stability

作者：Benetti Federico; Biarnes Xevi; Attanasio Francesco; Giachin Gabriele; Rizzarelli Enrico; Legname Giuseppe^*

来源：Journal of Molecular Biology, 2014, 426(22): 3796-3810.

DOI：10.1016/j.jmb.2014.09.017

• N-terminal domain
• disulfide bond
• intermediate state
• prion-susceptible species
• energy landscape

Prions are responsible for a heterogeneous group of fatal neurodegenerative diseases, involving post-translational modifications of the cellular prion protein. Epidemiological studies on Creutzfeldt-Jakob disease, a prototype prion disorder, show a majority of cases being sporadic, while the remaining occurrences are either genetic or iatrogenic. The molecular mechanisms by which PrPc is converted into its pathological isoform have not yet been established. While point mutations and seeds trigger the protein to cross the energy barriers, thus causing genetic and infectious transmissible spongiform encephalopathies, respectively, the mechanism responsible for sporadic forms remains unclear. Since prion diseases are protein-misfolding disorders, we investigated prion protein folding and stability as functions of different milieus. Using spectroscopic techniques and atomistic simulations, we dissected the contribution of major structural determinants, also defining the energy landscape of prion protein. In particular, we elucidated (i) the essential role of the octapeptide region in prion protein folding and stability, (ii) the presence of a very enthalpically stable intermediate in prion-susceptible species, and (iii) the role of the disulfide bridge in prion protein folding.

• 出版日期2014-11-11