Question #871ca
1 Answer
The hypothesis is that it induces misfolding of other proteins.
Explanation:
The theory that proteins can behave like pathogens has been proposed decades ago as a mechanism that causes diseases, known as 'transmissible spongioform encephalopathies' (TSEs) or better known as prion diseases.
Two well known examples of prion diseases are:
- Bovine spongioform encephalopathy (BSE) or 'mad cow disease'
- Creutzfeldt-Jakob disease (CJD), the human form of BSE
The hypothesis is that a misfolded version of the prion protein (PrP) can 'replicate' itself by transforming the normal version of PrP into the misfolded form.
The exact mechanism has not been elucidated yet, but it appears that the misfolded protein acts as a sort of template causing the normal, healthy proteins to refold into the pathogenic form.
The misfolding can lead to inactivity, aggregation and accumulation of the proteins, causing tissue damage.
Pathogenic prions have characteristics similar to pathogens such as viruses and bacteria:
- they can multiply exponentially and can pass membranes
- transmission can occur between individuals (e.g. by blood); they can even be transmitted between different species
- resistance against proteases (enzymes that break down proteins) and the bodies defense mechanisms
- they can mutate , creating different forms of pathogenic prions
