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Tarantula Venom and Chili Peppers Share Receptor
FiReaNGeL writes "Scientists have discovered that venom from a West Indian tarantula has been shown to cause pain by exciting the same nerve cells in mice that sense high temperatures and the hot, spicy ingredient in chili peppers. The findings demonstrate that some plants and animals have evolved the same molecular strategy to deter predators — triggering pain by activating a specific receptor on sensory nerves. The research provides new tools to understand how these pain- and heat-sensing neurons work, and to help develop drugs that ease persistent pain."
Are they the same nerve cells that get excited when you hit them with a hammer?
This damned story has an advert with a spider at the top.
*shudder*
Contextual advertising or just fluke?
liqbase
Spider con carne... mmm...
init 11 - for when you need that edge.
Maybe I'm missing something, but should the headline "Tarantula Venom and Chili Peppers Share Receptor" not actually read "Tarantula Venom and Chili Peppers Target Same Receptor"?
:)
It would be truly shocking if they actually shared the same receptor... has that ever happened? A plant growing an animal cell? Just curious...
Incidentally, the article doesn't really say if the same proteins are used by the pepper and the arachnid to provoke this receptor. Somehow I doubt it, since TFA says that just simple heat from the sun, as well as "peppery food, mustard oil and other compounds" also target it. Seems more coincidental than anything; a porcupine and a cactus would be another example of a plant and an animal developing a similar defense mechanism, no? Plant or animal, we do all seem to share the same world here...
In case anyone's interested, this particular species of tarantula, Psalmopoeus cambridgei, is quite cool looking... not quite as cool as, say, Avicularia versicolor or Haplopelma lividum, but cooler than I expected.
>> The findings demonstrate that some plants and animals have evolved the same molecular strategy to deter predators -- triggering pain by activating a specific receptor on sensory nerves.
This doesn't sound right. If this assertion is correct, it implies that as an organism is developing, its evolution is not only based on its perception of the environment, but on the exact biological constitution of it. How can a tarantula, for example, "know" of the existence of such receptors in its predators?
I would imagine it works the other way around: predators developed a common sensory receptor to detect specific chemical threats, and trigger an immediate physical response in order to prevent further consumption.
-dZ.
Carol vs. Ghost
Eating hot chillies is knowen to relese endorphins, which is why they feel good to eat. Does this mean that people will be poisening themselvs with tarantulas to get a high?
OK... Am I the only jerk that think this was about 3 rock bands using some kind of not-on-the hype music distribution system?
[sigh]
Man, i need to get out a little.
D.
* = Ear for the laypeople
Stuck down a hole! In the middle of the night! With an owl!
Wherever did you get the wacky idea that evolution was intentional? Spiders don't evolve venom by choice. The ones that happened to secrete tequila just got eaten as party snacks and failed to reproduce effectively.
I would imagine it works the other way around: predators developed a common sensory receptor to detect specific chemical threats, and trigger an immediate physical response in order to prevent further consumption.
That's possible. But if the response evolved independently in tarantulas and chili peppers, it doesn't matter so much if the receptor is common to their predators; if tarantula predators and chili pepper predators had different receptors, probably the two species would have evolved to target different receptors. Tarantulas and peppers don't have to "know" what the chemical composition of the receptors are ahead of time; mutations will produce lots of chemicals, and if one of them happens to have a deterring effect on whatever eats them, the organisms that produce that kind of chemical will be naturally selected.
Alright! So when can I start getting bottles of tarantula sauce?
who thought the title sounded like something out of Rolling Stone:
..."
"New York punk group Tarantula Venom will be opening for the Red Hot Chili Peppers at the Receptor on 45th and Broadway
I am officially gone from
I think it might really be more a matter that the tarantulas whose venom activated these receptors had a far greater success in the wild; I don't think it's particularly accurate to say that things evolve based on their perception of their environment because, well, no one chooses how they evolve (though we're coming damn close to being able to).
"Your mouse has been moved. Windows 95 must be restarted for the change to take effect."
Those new mutant therefor happen to have discovered a better way to defend themselfes from potential predators and other menace. They survive better, have more descendant, and become more abundant.
Per the "survival of the fittest" principle of evolution, the ability to defend oneself is an important feature and selective pressure will tend to favorise its evolution.
Several mutation latter, the venom compound was refined and we reach the modern tarantula, with its amazing ability to trigger capsaicin receptors and cause pain and burning sensation to defend itself.
That's another possibility. It is also possible the actual story is a much more subtle combination of the two : the predator may have evolved some way to detect chemical threats (and it's an useful threat to avoid food poisonning), and the prey may have found a way to hijack this alarm system to defend itself by evolving a compatible venom (in a way avoid being eaten by camouflaging as a toxic food).
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
This doesn't sound right. If this assertion is correct, it implies that as an organism is developing, its evolution is not only based on its perception of the environment, but on the exact biological constitution of it. How can a tarantula, for example, "know" of the existence of such receptors in its predators?
Knowledge doesn't enter the picture. Chili plants (and tarantulas) experiment with chemicals, the more painful ones live, and the less painful ones are eaten. They don't need to "know" why that happens, as long as they survive to reproduce.
I would imagine it works the other way around: predators developed a common sensory receptor to detect specific chemical threats, and trigger an immediate physical response in order to prevent further consumption.
The chemicals in question (capsaicinoids) are not dangerous, they're not chemical threats, it doesn't make any sense for mammals do evolve painful response to harmless chemical in a valuable food plant, but it does make a lot of sense for a plant to evolve a chemical that targets receptors that already exist in the animals - the ones for heat, and physical damage.
So you have a choice, suffer the toxin of the spider venom, or eat 16 million Scoville pure capsaicin crystals and lose the feeling in your face forever?
Fuck it, I'll take my chances with the spiders!
I start to feel worried when I see a post on slashdot that makes more sense to me than what the scientific article says. To me that means that the standard of conclusions being made from scientific observations is very poor.
Australian running a company that does C# / C++ / Java / SQL / Python / Mathematica
That's a very interesting idea, I don't have sufficient knowledge of vanilloid receptors to judge entirely.
However, beyond their powerful spice effect, chillis (modern ones at least) don't pose a 'specific chemical threat'. So, a receptor inducing pain is unlikely to have offered a selective benefit for its carrier.
In the case of a spider, they certainly wouldn't need to 'know' of the existence of a specific receptor. Those that were able to induce pain in a predator would be more likely to have a reproductive advantage than those that don't, resulting in the survival and reproduction of pain causing spiders. This would suggest that the ligand evolved to fit the receptor rather than the other way around.
Ye have made your way from the worm to man, and much within you is still worm.
What Bug-eyed Earl might say about that
Until tarantula venom shows up at stores like http://mohotta.com/ :)
(Considering that they already sell "Blair's Megadeath Hot Sauce" and "Bee Sting Honey Mustard Hot Sauce".)
http://www.thottbot.com/?i=19426
What kind of awsome job do you have where you get to feed chili peppers to mice, and then inject them with venom all day.? They actually get paid for to torment little rodents. A kids dream....
Ad eundum quo nemo ante iit!
The active ingredient in chili peppers has been used as a topical pain relief treatment for ages, you can buy it over the counter. It's also the active ingredient in that self-defense pepper spray. The more you know...
Slashdot Burying Stories About Slashdot Media Owned
'Receptor' in this case refers not to a cell, but to a specific protein structure called TRPV1. Many proteins exist in both plants and animals, particularly the ones most fundamental to life, such as those needed for DNA replication. This may be a little further afield, but it's really not shocking at all.
Further, TRPV1 (more familiarly known as capsaicin receptor) is, in fact, activated both by heat from traditional sources (the sun, a stove, etc.) but also by things which we perceive as hot (such as peppers, many if not most of which contain some amount of capsaicin). The tarantula venom studied also triggers this receptor. So it's not terribly surprising that all three types of stimulation--real heat, peppers, and the venom--produce similar sensations.
The most likely explanation for this is that the receptor existed first, and ancient proto-tarantulas who made venoms that could stimulate it were more effective at killing prey or chasing off predators. So it's not coincidence; it's just another example of nature building on what's available.
A biochemist friend of mine was telling me about some of his prospective research projects some time ago. It turns out that the receptor for capsacsin and for high temperature are one and the same, and what's unusual about these receptors is that they are not on the cell surface where most receptors are, but within the cell. This explains why it takes a little while for hot peppers to give you that tingle, and why it takes a while for it to go away, btw.
It makes perfect sense for the spiders to develop for those receptors.
Take 100 spiders and 100 predators. Let's say all the spiders have different poisons but only 20 have (even if by chance) the venom to trigger their predators' receptors. Those 20 won't be eaten, they'll survive and breed and create new spiders that have venom effective against their predators. This will be refined so that the most effective against the predators continue to breed and those who are not effective don't.
You're theory works too, it's a kind of chicken/egg question.
why their music was poison to my ears.
^_^
"it implies ..."
It doesn't. Nowhere does what you've quited imply that either spider or plant know anything about their environment. They simply "know" that they've not been eaten and can spread their seed - and thus (continue to) do so.
FatPhil
Also FatPhil on SoylentNews, id 863
Suppose there are 100 tarantula communities scattered around the globe. 99 of them have a weak poison that predators cannot taste. One of them leaves a burning sensation. After a couple of sacrificial tarantula the remaining in the community may live unmolested.
Same concept as for the plant.
As my father lik@(munch munch)...
It had to be said ...
Insert
Not as tasty. At least I assume they aren't.
The world is made by those who show up for the job.
This doesn't sound right. If this assertion is correct, it implies that as an organism is developing, its evolution is not only based on its perception of the environment, but on the exact biological constitution of it. How can a tarantula, for example, "know" of the existence of such receptors in its predators?
I would imagine it works the other way around: predators developed a common sensory receptor to detect specific chemical threats, and trigger an immediate physical response in order to prevent further consumption.
I'd say it's probably both -- the predators developing a more or less generic sensor for various threats, and the spiders/plants developing toxins that triggor the recptors in the predators.
As to how the tarantula "knew" of the existence of the receptors, the answer is easy: tarantulas whose toxins did not target the pain receptors of predators did not have a deterrent effect and were eaten, tarantulas whose toxins did target the receptors discouraged predators and were eaten less.
Evolution never "knows" that a particular trait is going to be good or bad, it just happens and then it either works or it doesn't. Whether a particular trait works or not will, in many cases, depend on the exact biological constitution of the environment around the organism, and so you shouldn't be surprised at all.
The enemies of Democracy are
From what I've read, capsaicin works by altering the temperature set point for nerves. Sort of like messing up the calibration to temperature. The temperature that causes a burning sensation is lowered to below body temperature. Which also explains why cold drinks tend to help. On a related note, wintergreen oil (and related chemicals) do the opposite: set the cold sense higher. Apparently both work on the same pathway.
Which makes me curious if anyone has combined chile with wintergreen and what happened.
The world is made by those who show up for the job.
This particular species is still crawling the earth because it happened to produce a useful venom. The other species, umm, didn't do so well.
Thats natural selection for you.
"Let me know, because soon I'll be out of a job like Rummy, and need a new one." -- Dick Cheney
The findings demonstrate that some plants and animals have evolved the same molecular strategy to deter predators -- triggering pain by activating a specific receptor on sensory nerves.
I'm trying to remember the last time I was bitten by a chili pepper.
Here's the source, not a (plagiarising?) blog.7 2/
http://pub.ucsf.edu/newsservices/releases/2006110
That's a basic feature of evolutionary theory; the actual environment, and what works and doesn't work in it, is what drives evolution, not any organism's perception of the environment.
It doesn't, and it doesn't need to. Evolution is driven by changes not driven by perception or design, and if those changes are net beneficial to fitness, they tend to spread in the population and be reinforced, if they are a net harm to fitness, they tend to die out in the population.
It may seem odd that capsaicin, a pain-causing compund, can relieve pain. Based on research, it appears that the receptors targetted by capsaicin can eventually become "fatigued", and stop responding, thus easing pain in the case of arthritis or shingles. A doctor friend of mine told me he was once involved in capsaicin pain-relief research. According to him, they injected several rabbits with a relatively pure capsaicin extract. The rabbits writhed in agony for an entire night, but the next day seemed calm and normal. They were put through a battery of tests, and to the incredulity of the researchers, they didn't respond to any pain stimulus whatsoever. It was (he said) as though they'd been completely and permanently anesthetised. In effect, they had "burned out" the capsaicin receptors of the rabbits.
@ 16787299 : It's not plagiarism, everything on the site are copyright free press releases. We just aggregate the best ones (manually chosen by me - Im a phd student in retrovirology / bioinformatics).
Eureka Science News - automatically updated
Tarantulas as a species can "know" about their environment through selection pressure: that is, tarantulas and peppers without an effective deterrence are eaten.