Question

Prion replication depends on the presence of a protease. True or False True False

Answer 1

False.

Prions are infectious agents in form of proteins, which divides on their own inside the host body. They are misfolded in nature and results in neurodegenrative disorders in humans or animals like alzhimers, parkinsons, scrapie (in sheeps). Because of misfolded structure they are present in the form of protein aggregrates called amyloids which on accumulation in tissue cause abnormalities and ultimately, cell death.

The normal form of prion protein is present in animals and called as PrPC, while the misfolded/infectious form is called PrPSc where C refers to 'cellular' PrP and Sc refers to 'scrapie' from the prion disease in sheep. PrPC is structurally well-defined and normal but PrPSc is polydisperse and aggregrated.

Due to the change in structure of protein, they usually pass through proteases, protein degrading enzymes and therefore neither requires them for replication or survival.