What exactly is a "prion"?

Question

My Biology textbook says that a prion is a protein molecule that causes other proteins to become prions, but WTF does that mean? That doesn't explain anything to me. :/

Answer 1

A prion is a protein that is infectious. In fact the name really would make more sense if it were "proin" for protein infectious, but the one who coined the name "prion" thought it sounded better than "proin".

Just think of a prion as an infectious agent like a virus, but chemically it's a protein. And instead of replicating itself like viruses, it affects other proteins so that they fold in certain ways to become prions, and that's the way it "spreads". These prions damage cells in the body.

Answer 2

lol!  Don't you hate it when bio texts do that?  more to come...

A PRION is basically this little evil invading thingy scientists found in the brains of people/animals that had developed degenerative wasting disorders (ie, mad cow disease).  I'm not sure if there are actually different types, or if they all look exactly the same (this was more what I seem to be feeling, but really don't remember).  Anyway, the interesting thing is, they're much different from virii.  A virus acts kind of like a living microbe- it attaches to a cell, "infects" it with it's genetic material, which usually is used to make new little virii and destroys the cell in the process.  PRIONs, however, are much simpler.  They don't infect anything, they just sort of bump into it and accidentally destroy it.  Keep in mind they're working on the (much smaller) molecular level.  Basically, when one PRION bumps into it's unfortunate victim (a protein), that one's structure changes- it deforms and can't function any more.  Remember how proteins have different structures?  Primary, secondary, tertiary, etc, etc?  I think it works to unravel it into one of the other forms, or something similar to that.  However it works, once finished, this new franken-protien also has the ability to convert it's neighbors- and the result is a nasty downward spiral.  

When we were kids, a buddy & me used to get out a pan of really hot water, and see how much sugar we could dissolve into it.  (You can load a lot of it in there)  Then you put it (in liquid form) in the freezer.  After it freezes, it makes a kind of clear gel- like a very thick syrup.  But if you cut into it with a knife, all of the sudden the sugar starts to crystallize- in a wave across the whole pan all of the sudden all of your sugar goes out of it's dissolved form and converts into a crystal form.  That's kind of the way PRIONs work, except with proteins.

Answer 3

prion is made up of two words proteinaceous and infectious . Prions are thought to cause a number of diseases in a variety of mammals, including bovine spongiform encephalopathy (BSE, also known as "mad cow disease") in cattle and Creutzfeldt-Jakob disease (CJD) in humans. protein from which prion is made up of are present even in healthy individuals. however due to different folding pattern of the prion it is resistant to enzyme protease.Prions are hypothesized to infect and propagate by refolding abnormally into a structure which is able to convert normal molecules of the protein into the abnormally structured form. All known prions induce the formation of an amyloid fold, in which the protein polymerises into an aggregate consisting of tightly packed beta sheets.

Answer 4

Prion is a protein particle capable of infection without DNA or RNA.