Why do prions refold into a different structure?

Why do prions refold into a different structure?

• A. They are extremely stable and accumulate in infected tissue, causing cell death and tissue damage; resistant to denaturation.
• B. They are easily denatured.
• C. They rely on host enzymes to refold.
• D. They cannot accumulate in tissue.

Answer: (A)

Prions refold into a different structure because the abnormal form is extremely stable and resistant to denaturation, so it can persist in tissues and act as a template to convert normal prion proteins into the same misfolded shape. This template-driven conversion means once the first misfolded prion (PrPSc) forms, it interacts with normal PrP and induces it to adopt the same beta-sheet–rich, protease-resistant conformation. As more PrPSc accumulates, it aggregates and damages neural tissue, producing the disease symptoms. This process does not rely on host enzymes; the prion’s own structural properties drive the refolding and propagation.

Prions refold into a different structure because the abnormal form is extremely stable and resistant to denaturation, so it can persist in tissues and act as a template to convert normal prion proteins into the same misfolded shape. This template-driven conversion means once the first misfolded prion (PrPSc) forms, it interacts with normal PrP and induces it to adopt the same beta-sheet–rich, protease-resistant conformation. As more PrPSc accumulates, it aggregates and damages neural tissue, producing the disease symptoms. This process does not rely on host enzymes; the prion’s own structural properties drive the refolding and propagation.