Explain the Nucleation-Polymerization Model for the Propagation of the PrP^Sc

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The Answer is This model states that the conformational change that causes PrP^C to fold into PrP^Sc is a spontaneous and reversible reaction.This model also states that monomers of the PrP^Sc protein are less stable than Prp^C,so that very little of the scrapie conformation would accumulate.If a person were "infected" with some of the PrP^Sc form of the protein,this would act as a "seed" to bind to the unstable PrP^Sc proteins and stabilize its conformation.These would also cause the PrP^Sc proteins to aggregate with each other and form fibrils,which would foster even more conversion of PrP^C to PrP^Sc.In the genetic form of the disease,mutations in the prion protein would increase the stability of the PrP^Sc form or enhance its ability for form aggregates,which would also stabilize the scrapie conformation.The alternative model suggests that the PrP^Sc form of the protein is more stable,but unlikely to occur.Here the exogenous PrP^Sc protein would act as a chaperone to induce folding of PrP^C into PrP^Sc.Mutations are predicted to increase the rate of refolding of the normal protein into the scrapie conformation.

Explain the Nucleation-Polymerization Model for the Propagation of the PrPSc

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Explain the Nucleation-Polymerization Model for the Propagation of the PrP^Sc