When foreign pathogens, such as bacteria or a virus, enter our body, our immune system responds in a concerted effort to eliminate them. B cells produce antibodies that recognize markers (called antigens) on the surface of the invaders; these antibodies are then used to tag foreign pathogens for destruction.
B cells typically require interaction with T cells for full activation and antibody production, which is critical to overcoming an infection. But there are some cases where the T cells are not required. Now, researchers have figured out how this works—and discovered that it relies on the remains of long-dead viruses that litter our genomes.
Large, repetitive sugar structures that are often found on the surface of bacteria and viruses are the key to activating antibody production without the help of a T cell. These sugary structures engage proteins called B cell receptors, which activate the B cells. B cells then grow, forming short-lived cells that produce antibodies and long-lived memory cells that will recognize the same invader upon subsequent infection
http://arstechnica.com/science/2014/12/remains-of-long-dead-viruses-in-our-genomes-aid-our-immune-response/
[Abstract]: http://www.sciencemag.org/content/192/4238/467
(Score: 3, Funny) by buswolley on Friday January 02 2015, @12:55AM
I want to say how cool this article is...too bad its on a slow traffic day
subicular junctures
(Score: 0) by Anonymous Coward on Friday January 02 2015, @03:47AM
Correct URL: http://www.sciencemag.org/content/346/6216/1486.abstract [sciencemag.org]
(Score: 2) by kaszz on Friday January 02 2015, @03:57AM
Does this mean there isn't any junk DNA really?
(Score: 2) by buswolley on Friday January 02 2015, @04:56AM
Junk DNA is an old concept that just doesn't really make sense anymore, I think...although I could be wrong (not my field after all)
subicular junctures
(Score: 2) by HiThere on Friday January 02 2015, @06:46PM
FWIW (also not my field) I think there is still lots of "junk DNA", just nowhere near the amount that there was once thought to be. Think of it as a hard disk that's seen a lot of use. You end up with a lot of pieces of files that were once used, but aren't used anymore. Of course, since in this case the presence of the "partial files" affects how the DNA bends, it still has some utility, but it's (nearly) only significant how long it is, not precisely what it contains.
But there are lots of things that were once called "junk" and are just control signals of some sort. And probably some of the things that currently appear to not have any use will turn out to have utility. But not all of it. If it weren't for real "junk" DNA we'd still be dichromats rather than trichromats. Sometimes the junk DNA will mutate, and the new version will turn out to have utility, and then no longer be junk.
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 1) by dltaylor on Friday January 02 2015, @04:02AM
If our genome is still reproducing them, then they're hardly "dead", just incredibly successful.
There's a theory around, not confirmed, AFAIK, that some diseases, such as MS, are the result of activation of an embedded virus.
(Score: 2) by Tork on Friday January 02 2015, @06:15AM
🏳️🌈 Proud Ally 🏳️🌈
(Score: 2) by HiThere on Friday January 02 2015, @06:52PM
Well, it depends on what you consider the virus. The thing they're talking about is sugars found on the outside of the virus, not it's reproductive core. (I can't say DNA or RNA, because different viruses are different...so I said reproductive core.) This would be analogous to someone stealing your skin after killing you, and starting to make copies of it. You wouldn't consider that you were reproducing just because copies of your skin were being made.
(Well, actually that's not a good analogy. If the entire virus coat were embedded in the gene it would be a really poor analogy, because that's about half the virus, but this is only a piece of it's coat, so the analogy is better.)
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.