Disassociation of β1-α1-β2 from the α2-α3 domain of prion protein (PrP) is a prerequisite for the conformational conversion of PrPC into PrPSc: Driven by the free energy landscape.

Disassociation of β1-α1-β2 from the α2-α3 domain of prion protein (PrP) is a prerequisite for the conformational conversion of PrPC into PrPSc: Driven by the free energy landscape. Int J Biol Macromol. 2019 Jun 14;: Authors: Chandrasekaran P, Santosh Kumar C, Rangachari K, Sekar K Abstract Misfolding of the cellular prion protein (PrPC) into β-sheet-rich scrapie form (PrPSc) is associated with transmissible spongiform encephalopathies. A point mutation F198S is responsible for the development of a rare inherited Gerstmann-Straussler-Scheinker disease caused by the aggregation of PrPC. Thus, identification and the structural characterization of aggregation-prone regions are essential to delineate the conversion of PrPC to the disease-associated PrPSc upon F198S mutation. In the present study, molecular dynamics simulations on the wild-type PrP (WT-PrP) and its mutant were performed to explore the structural basis responsible for aggregation driven by the mutation. Secondary structure analysis revealed that the mutant exhibited a partial unfolding on α2 and the complete distortion in the 310-helix of the β2-α2 loop. Remarkably, the β2-α2 loop is in proximity to α3 attributed by the long-range hydrophobic interactions and such structural intimacy is not observed in the WT-PrP. Owing to this, the β1-α1-β2 regions have separated from α2-α3 domain resulting in the impairment on the hydrogen bond between α1 and α3. Thus, ...
Source: International Journal of Biological Macromolecules - Category: Biochemistry Authors: Tags: Int J Biol Macromol Source Type: research