What are prions?

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A few days ago I commented on how proteins are molecular complexes made up of amino acid sequences that are the blocks of life and how, depending on the amino acids that make it up, their number and order, the protein performs different functions.

In addition to this, the three-dimensional shape that the protein acquires once synthesized is also decisive, this three-dimensional way of folding depends on the amino acids that make up the protein.

Upon completion of the RNA transcription sequence within the ribosomes, the protein folds and twists in a way that will define its subsequent functions.

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If this folding is not done properly, not only will the protein not be able to perform its usual functions, but it will become a prion that can "infect" other proteins.

Although they do not contain any type of DNA, RNA, or any other type of genetic material with instructions, prions are able to "infect" other proteins in their class by causing them to change their folding shape and become other prions.

As in a zombie movie, prions infect other proteins that become prions and these, in turn, infect other proteins, producing a chain reaction.

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Although a priori it may seem very far to you, surely you all remember the episode of "Vobina spongiform encephalopathy" that affected cattle and what went down in history as "mad cow disease".

This pathology caused by prions, affects the cells of the nervous system, leaving the brain as gruyere cheese bubbles and that is why it is called "spongiform".

This disease could be transmitted to humans and was known as "Creutzfeldt-Jacob" disease, so as you see these prions are more famous than you thought.

More information:
https://en.wikipedia.org/wiki/Prion#:~:text=Specialty,humans%20and%20many%20other%20animals.
https://en.wikipedia.org/wiki/Bovine_spongiform_encephalopathy

Versión en español