system
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human
How do Prions transfer their shape to other proteins?

All I could find is the are ABLE to do this, but how do they do this? Aren't prions just a misfolded protein? How could they reshape a protein?
gpt
Generically speaking, when proteins misfold, it can expose regions which are normally buried within the protein. These regions can bind to the surface of other proteins, destabilising their “normal” shape and stabilising the misfolded shape. These exposed regions are often hydrophobic, meaning they “hate water” and it’s energetically unfavourable for them to be exposed to it, so the misfolded proteins then aggregate, clumping together, and the cycle repeats.

Looking at a 2019 review, it looks like the best current models point to a seeding/nuclear ion process where prion fragments can act as a seed/template, catalysing incorporation of previously healthy protein into a polymer aggregate; eventually the polymer fragments and each of the new fragments in turn can act as a seed.