After Death, Hundreds of Genes Spring Back to Life 62
Two surprising studies reveal new information about what genes do after death. Slashdot reader gurps_npc writes:
You think your body stops after death, but up to two days later certain genes may turn on and start doing stuff for another two days before they give up the ghost. We are all zombies for up to four days after death.
Gizmodo reports that in fact "hundreds" of genes apparently spring back to life. "[P]revious work on human cadavers demonstrated that some genes remain active after death, but we had no idea as to the extent of this strange phenomenon."
Gizmodo reports that in fact "hundreds" of genes apparently spring back to life. "[P]revious work on human cadavers demonstrated that some genes remain active after death, but we had no idea as to the extent of this strange phenomenon."
Random stuff (Score:3)
As the cellular systems decay, there is probably lots of random stuff going on. Normal feedback pathways don't work. It's impossible to predict. But there is not really a reasonable mechanism for evolutionary selection for these processes so even the ones that make sense (like stress reaction or immune stimulation) are just vestigial precesses. Not interesting.
Re: Random stuff (Score:1)
It explains why scientists were measuring brain activity in fish that had been dead for days. They took a fMRI scanner, cranked up the sensitivity and watched for activity.
Re:Random stuff (Score:5, Interesting)
I can imagine one (not saying it is at work here). If some residual activity reduced the chances of harmful (to the still living) bacteria taking hold, it might confer a slight advantage to the still living relatives of the deceased.
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Probably not. Rotting cadavers are nauseating, and stressful to the living, but they are not health threats. Really, they are not. [who.int]
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Sure, NOW they aren't.
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There is no need to assign any motives here. Sometimes I feel people have decided that when they abandon a belief that everything must have a purpose assigned by a micromanaging deity they retain some of that and insist that everything must have an evolutionary reason. People seem scared of randomness, meaninglessness, chaos. Then combine this with a warped idea of what evolution is (that it's to improve species) and this gets magnified. Thus they feel there must be an evolutionary answer to why there a
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I merely suggested a potential (though unlikely) advantage that could be at work. I also offered my doubts. More an exercise in imagination.
Archaic Leftover? (Score:2)
We inherit a vast majority of our genes and genetic patterns from our archaic forebears; in humans, many of these older systems are turned off, in effect. This is not news. What use these genes may have had in extinct life forms hundreds of millions of years old is open to question, as is the potential evolutionary usefulness of reusing simple cellular material. In other words, single-cell organisms or those made up of semi-specialized groups of cells may have used these genes to "come back to life" if and
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just vestigial precesses. Not interesting.
Are you sure, i am not a medical doctor or even a biologist but it seems like studying how some of our processes behave under abnormal situations might be very interesting. Some of the behaviors might be useful for preserving life if we could trigger them on demand. They might be things we could identify and guard against when trying to save someone.
"His kidneys are shutting down" - Well okay why is that, can me maybe make them not do that, instead of prescribing dialysis and an eventual kidney transplant
Its simple (Score:4, Interesting)
Re:Its simple (Score:5, Interesting)
A large portion of our (and virtually all other life) is partially composed of virus-inserted code.
To a virus, life isn't really a thing to begin with, only DNA interactions, with rare opportunities to copy.
From that perspective, death of the host body just means it's bacteria party time, and even if 99% of organelles used to copy are kaput, almost all viruses are bacteria-predators anyway. So, hiding away in human DNA for a few hundred generations or whatever is just a distraction from getting to the (ambiguous) goal of a bacteria to infect.
So, now that they're not suppressed, some random virus code passively sends a request to the organelles to write a copy of themselves for the 83rd billionth time, and this time don't get their message scrambled. All this happens trillions of times, infects perhaps millions of bacteria that manage to escape, which spread off into the world to keep the messy process going.
Niches for DNA code are massively multidimensional, and even though the possibility space for success is outrageously sparse, the life that lives in the outer reaches of possiblity doesn't have be intelligent to know it's a bad idea, and so spreads where we can't imagine. Things like life that only has the chance to reproduce every few hundred years (using another life form's mechanisms to keep their DNA active in the meantime), or has to jump between 3 species in order to continue a full reproduction cycle.
Heck, the only reason we can move around and talk and stuff is because some odd other microlife got mixed in with an ancestors cells to become mitocondria. With that, we can live away from immediate energy sources, and use sugars. To this day, bacteria are constantly mixing DNA with eachother, getting into the oddest combinations, with some help from viruses, who get everyone else involved in the party.
And from a microscopic perspective, we're mostly mobile apartments for bacteria, that protect the bacteria/helpful viruses we like from the bacteria/viruses that tend to wreck the apartment. Fortunately, most bacteria are boring tenants, and most viruses only target bacteria.
Ryan Fenton
Re: (Score:3, Insightful)
A large portion of our (and virtually all other life) is partially composed of virus-inserted code.
To a virus, life isn't really a thing to begin with, only DNA interactions, with rare opportunities to copy.
From that perspective, death of the host body just means it's bacteria party time, and even if 99% of organelles used to copy are kaput, almost all viruses are bacteria-predators anyway. So, hiding away in human DNA for a few hundred generations or whatever is just a distraction from getting to the (ambiguous) goal of a bacteria to infect.
[...]
Niches for DNA code are massively multidimensional, and even though the possibility space for success is outrageously sparse, the life that lives in the outer reaches of possiblity doesn't have be intelligent to know it's a bad idea, and so spreads where we can't imagine. Things like life that only has the chance to reproduce every few hundred years (using another life form's mechanisms to keep their DNA active in the meantime), or has to jump between 3 species in order to continue a full reproduction cycle.
I'm not sure this story holds up. The moment a virus gene is inserted into our genome its reproductive cycle becomes tied to ours. Even if some virus DNA could escape our cells and infect bacteria post-mortem they'd just become ordinary viruses.
The only way for genes to retain function is for that function to be subject to natural selection. But as long as those virus genes are trapped in a human DNA strand the only way for them to propagate is through people, and the moment they escaped they'd be tied
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Somehow doubtful. When talking about some corpse getting stiff, this is usually not what is meant.
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Then it usually happens at the moment of death, not after he's been cut down and stowed in the mortician's office for a while.
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the opposite would be even more impressive.
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Click bait? (Score:5, Interesting)
What's that article beside click-bait?
"previous work on human cadavers demonstrated that some genes remain active after death" What does mean "remain active" with regards to genes? For all that I know (and I own a Biology major) genes just "stay there" (more or less) for RNA to make use of them so, what this does mean? That supressing factors, as they are supressing no more after death, allow for some genes to be expressed after death? What a surprise! I don't mean the details not to be worthnoting as I'm not aware too many time/money has been thrown towards that target but that the general assertion is of little surprise. We already knew death is not an event but a process (despite all legal interest in the contrary).
Re:Click bait? (Score:5, Funny)
For all that I know (and I own a Biology major)
Owning people is morally wrong. I really think you should let that poor student go.
Re:Click bait? (Score:5, Funny)
I am a CEO, you insensitive clod!
It's Gawker. So... nothing. (Score:2, Flamebait)
What's that article beside click-bait?
Being that Gizomodo is a part of the Gawker shithouse - it's all clickbait all the time.
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Ahmad, you forgot again to use the new weekly encryption algorihm. I told you many times you have to do "git pull" every Saturday before sending communications otherwise the sleeper cells can't decrypt the message.
One more screwup like this and you're going back to AK-47 polishing duty.
Life cares about the herd not the individual (Score:2)
Though the individual dies, the life "virus" (DNA, genetic material) leaps from host to host. From what I've seen and read, it seems that the individual's behavior and its life and death itself are designed, by the "virus", to maximize the health and size of the herd. In that context, it could well be mechanisms are then activated to quickly break down the individual body back into its components for re-use, which maximizes herd health in some way.
However, that could be driven to maximize not merely the po
Your computer changes after you turn it off! (Score:5, Funny)
Sometimes, after you turn your computer off, activity does not immediately cease! There are various thermal adjustments which continue to happen for hours after power down! Sometimes random electrical signals can be sent for no apparent reason!
Seriously, the human body is a complicated chemical plant without centralized control. Some stuff keeps happening. Other stuff doesn't. Big deal.
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I remember you could switch an Atari 80 off and switch it back on again and the RAM boards still had the contents that were present before the system was switched off.
You mean the cold boot attack [wikipedia.org]? Memory keeps readable for minutes after power-off, which can be drastically prolonged by rapid refrigeration.
Re:Your computer changes after you turn it off! (Score:4, Funny)
The solution is obvious, ask Poettering to integrate a systemd process to terminate every gene that isn't properly killed.
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And he would require everyone who dies the old way to adjust to his change.
We are not truly dead. (Score:1)
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We already do this. In some surgeries the body is cooled to the point where the brain and heart cease to function temporarily. But in normal situations the cells of the body, especially the important ones in our brain, are not capable of being awoken long after we stop breathing. At normal temperatures brain damage begins within minutes and that can not be undone.
Is that really surprising? (Score:2)
Considering we're not really a unitary being, but more or less a hundred million separate entities living in a staggeringly complicated symbiosis, is this really a shock?
Complex systems don't just "stop" on a dime; there's energy distributed through the system that ultimately will be used locally before local processes stop.
Obviously, the 'independent' organisms within us continue to operate after death - bloating, decomposition, etc. How different is it if some of our own more-dependent bits keep cycling
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Technically do you ever really "die"? There's so much bacteria and other things running around in the body, it's more like you get recycled.
Nothing goes to waste, but it's just not "you" any more. Stick a body in a sterile atmosphere and come back to teeming life using whatever resources it can for as long as it can, even if that's moulds or bacteria or mites or whatever. Isn't there something like thousands of mites per square foot of the body skin alone?
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Technically do you ever really "die"?
That's a good question
Nothing goes to waste, but it's just not "you" any more.
Oh right. Never mind then.
Pre-print article (Score:3)
Here is the pre-print article:
http://www.biorxiv.org/content... [biorxiv.org]
Surprising? No, and yes (Score:2)
While a lot of Slashdotters might see the summary and say, "Duh!", it is a largely unexplored area of biology. Since "Biology" literally means "the study of life", it shouldn't be surprising that not too much time is spent on what happens after death.
A simple explanation for some of the changes in gene expression probably relates to the fact that the organs are no longer working together to keep the organism alive. Furthermore, cells within an organism are in competition for the increasingly scarce resource
Nobody yet? OK. (Score:3, Funny)
Things unexpectedly activating is usually due to a virus that goes by the common name of systemd.