Re:The Case for Transmissible Alzheimer's Grows
by nonbel on Sunday February 10, 2019 @09:37PM
(#19131646)
>"so far all symptoms of prion-type disease for which a cause has been found have turned out to be associated with errors in PRNP."
Thanks, this is an interesting new fact to me if true. Is there a source for it?
I don't mean a source proving there are no others or something else silly like that. I mean like a review article that mentions they couldn't find any publication about any amyloid beyond PRNP-derived ones being transmitted.
Re:The Case for Transmissible Alzheimer's Grows
by escape_goat on Monday February 11, 2019 @08:01AM
(#19134079)
I can't give you a source like that. From the Wikipedia article on prions, it appears that several prion-based diseases are suspected, but that so far the only proven cause for such a disease has been the "major prion protein." In 2015 a hypothesis was advanced that multiple system atrophy (Shy–Drager syndrome) was caused by a prion form of the alpha-synuclein molecule. However, if any subsequent proof has followed, neither the wikipedia pages on prions or alpha-synuclein have caught up with that.
PRNP is the gene encoding for "the major prion protein." Several different errors in PRNP create versions of "the major prion protein" that can be folded in a way that is bad (the prion folding). However, that is not the only way in which the proteins can fold themselves.
When lots of these proteins stuck together in an 'amyloid' (starch-like) aggregation, a misfolded (bad) shape of the protein serves as a template, folding more and more instances of the protein into the bad shape.
We consider the shape to be 'bad' because it is associated with visible symptoms of disease.
It is the prion ('bad') folding of a protein which would be infectious.
There are lots of different proteins that create amyloids, but so far all symptoms of prion-type disease for which a cause has been found have turned out to be associated with errors in PRNP.