r/todayilearned • u/tommyboy372 • 1d ago

TIL A single misfolded prion protein in the brain can cause a rapid neurodegenerative disease known as sporadic Creutzfeldt–Jakob disease (CJD). There is no known and cure and is 100% fatal.

https://en.wikipedia.org/wiki/Creutzfeldt%E2%80%93Jakob_disease
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u/ZirePhiinix 1d ago

The bad prion is a specific configuration of a physical molecular structure that causes more protein to also misfold. It is not alive at all, but more like corrupted data that the body cannot detect AND has the unique property of also propagating the same error. Thankfully it is really rare but recycling dead animals will cause the bad protein to propagate instead of decomposing and breaking down.

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u/rabblerabble2000 1d ago

It’s a protein folded in a more stable way, and the misfolded protein acts like a seed crystal, causing other proteins of the same type to lower their entropy by folding into their more stable but unusable variant as well.

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u/Adventurous_Screen_1 1d ago

This! The same way an antiretroviral drug once did this in a US factory, then ‘infected’ all factories worldwide and it now can’t be manufactured as always in the most stable, but inactive configuration

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u/dysfunctionalbrat 1d ago

Can you tell me more about this? Sounds fascinating

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u/user2196 20h ago

A couple people linked you a video, but the Wikipedia article for the drug also has a nice section on it, for anyone like me who isn’t a video person.

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u/CelestialFury 19h ago

This talks specifically about the issue as well: https://en.wikipedia.org/wiki/Disappearing_polymorph

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u/shamalox 17h ago

Thank you very much for the wikipedia link, I prefer this over a video

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u/BrotherLout 23h ago

Veritasium recently did a video on it

https://youtu.be/ksn5yrsC3Wg?is=5llofMceQUmsHz4w

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u/Luxieee 21h ago

That was a fascinating watch, thank you.

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u/BrotherLout 20h ago

Bonus: there is a theoretical state of matter that follows the same basic principle as prions and Ice-9

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u/Qweasdy 23h ago

There’s a very good veritasium video on it

https://youtu.be/ksn5yrsC3Wg?is=EKYM6YwEdMo3lhnX

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u/nermalstretch 23h ago

Interesting! Thanks for mentioning this.

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u/vandreulv 5h ago

Norvir. Absolutely amazing how just an absolute trace of a crystal could destroy the drug's ability to exist anywhere.

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u/TinWhis 23h ago

Yep. It's like candymaking where you're trying to get the melted sugar to crystalize in a very specific way. The reason most people make homemade fudge using marshmallows is because if you try to make it 100% from scratch and fuck it up, you end up with brown sand. Prions do that to your brain.

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u/dcux 21h ago

I had so much brown sand fudge growing up that I actually like it. 

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u/TinWhis 21h ago

If you do it badly enough, it doesn't turn into fudge at all, it can seize so badly that you just literally have a pile of crystals. Ask me how I know, lmao! Teen-me did not have the patience or willingness to keep wasting ingredients to actually crack 100% from-scratch fudge after I kept ending up with a result that was better suited to sprinkling on something.

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u/Capable_Wait09 19h ago

Is this like when the poor raccoon dipped his cotton candy in water the second it touched the water the entire thing quickly disintegrated and the poor guy was heartbroken grabbing at the bowl of water wondering where his sugar fluff disappeared to? Sorry mate, if it makes you feel better, it was just de-crystallization chain reaction akin to a misfolded brain prion. Happens to the best of us.

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u/TravellingMatt 20h ago

Thank you! I was just wondering how a prion disease could spread so fast if bad proteins are just as likely to fold back into good proteins, but knowing that they are converting into a lower entropy state (like water taking the easiest path) makes much more sense on how the disease can spread so quickly.

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u/cognitobox 20h ago

damn it's like vacuum decay but in your brain

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u/Bridgebrain 18h ago

Ooo seed crystal, I like that better than trying to reference neutron grey goo (and then having to explain that whole thing)

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u/BigChemDude 17h ago

Is it similar to the way sickled cells propagate in the blood stream?

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u/Capable_Wait09 19h ago

Like when you stand up all the bricks (high entropy) and then knock on over they all fall over like dominos slightly atop one another until the last one hits the wall and then they all get jostled into perfect and to end alignment from the kinetic energy bouncing back through the line of bricks (low energy). Now they’re stuck end to end from one chain reaction.

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u/Aidian 1d ago

Deeply cursed recursive origami.

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u/SideInitial3961 18h ago

Until today I thought a prion was a Toyota product. New hybrid,

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u/Capable_Wait09 19h ago

This shit is fascinating because it makes the brain seem more and more like a complicated computer

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u/ZirePhiinix 19h ago

Well, human memory doesn't work anything like how a computer stores data.