3 ms·

Recent research (2020) revealed these plants containt a potent protein neurotoxin: https://www.science.org/doi/10.1126/sciadv.abb8828 https://www.science.org/d

Recent research (2020) revealed these plants containt a potent protein neurotoxin: https://www.science.org/doi/10.1126/sciadv.abb8828 https://www.science.org/doi/10.1126/sciadv.abb8828 > "We show here that the venoms of Australian Dendrocnide species contain heretofore unknown pain-inducing peptides that potently activate mouse sensory neurons and delay inactivation of voltage-gated sodium channels. These neurotoxins localize specifically to the stinging hairs and are miniproteins of 4 kDa, whose 3D structure is stabilized in an inhibitory cystine knot motif, a characteristic shared with neurotoxins found in spider and cone snail venoms." It's remarkably stable: 100-yr old dried botanical specimens can still sting. This research is pretty difficult as the individual stinging hairs produce only tiny volumes of liquid, requiring the use of sensitive mass spectrometry techniques.

nemo44x 4y ago
Won't be long for this to be weaponized. Being able to chemically turn it on and off sounds like a "perfect" torture device that doesn't leave forensic evidence behind.
- photochemsyn 4y ago
  No need to go right to the worst case scenario. Cone snail venom, for example, has been a source of useful medicines: https://www.nist.gov/news-events/news/2017/10/how-cone-snails-deadly-venom-can-help-us-build-better-medicines https://www.nist.gov/news-events/news/2017/10/how-cone-snail...
1024core 4y ago
I always wonder: how tf did evolution end up designing such a thing?
- MagicMoonlight 4y ago
  A plant that is hurty gets eaten less and survives better. The hurtier it gets, the better it survives until it is the hurtiest.
- mkj 4y ago
  It coexisted when megafauna were still around so needed a severe effect to deter being eaten. That's the explanation our guide in the Daintree gave. 2 ton marsupials, for example https://en.m.wikipedia.org/wiki/Australian_megafauna https://en.m.wikipedia.org/wiki/Australian_megafauna
dopylitty 4y ago
I wonder if you could whip up a vaccine to generate antibodies against a part of the protein so that it can’t bind to the right places on the sensory neurons. Or heck maybe skip the vaccine and create some monoclonals against it. Although my understanding is that creating monoclonals usually requires isolating B cells targeting the right epitope from someone and sequencing them so some unlucky donor human or animal would need to touch the plant first.
hilbert42 4y ago
Thanks very much for that most interesting reference. (I'm sure I'd have seen it earlier if I'd not let my sub to Science expire.) "These irritation-inducing molecules include histamine, acetylcholine, 5-hydroxytryptamine as well as formic acid and other low–molecular weight organic acids." Having been stung by bull-ants and like brethren, I can attest that as bad and as painful as these formic acid/concoction-type stings were they pail against what I experienced from Gympie-Gympie. "…none of these small molecules in the volar forearm of humans was entirely sufficient to reproduce the symptoms of a Dendrocnide sting," That is also fully consistent with my experience. What I find so interesting about this paper (in addition to my interest through experience), is that these are newly discovered toxins which seems somewhat strange given the ubiquity of Gympie-Gympie and its well-known ability to inflict excruciating pain. Presumably, this discovery will spur on further toxins research.

nemo44x 4y ago

Won't be long for this to be weaponized. Being able to chemically turn it on and off sounds like a "perfect" torture device that doesn't leave forensic evidence behind.

photochemsyn 4y ago
No need to go right to the worst case scenario. Cone snail venom, for example, has been a source of useful medicines: https://www.nist.gov/news-events/news/2017/10/how-cone-snails-deadly-venom-can-help-us-build-better-medicines https://www.nist.gov/news-events/news/2017/10/how-cone-snail...

1024core 4y ago

I always wonder: how tf did evolution end up designing such a thing?

MagicMoonlight 4y ago
A plant that is hurty gets eaten less and survives better. The hurtier it gets, the better it survives until it is the hurtiest.
mkj 4y ago
It coexisted when megafauna were still around so needed a severe effect to deter being eaten. That's the explanation our guide in the Daintree gave. 2 ton marsupials, for example https://en.m.wikipedia.org/wiki/Australian_megafauna https://en.m.wikipedia.org/wiki/Australian_megafauna

dopylitty 4y ago

I wonder if you could whip up a vaccine to generate antibodies against a part of the protein so that it can’t bind to the right places on the sensory neurons. Or heck maybe skip the vaccine and create some monoclonals against it. Although my understanding is that creating monoclonals usually requires isolating B cells targeting the right epitope from someone and sequencing them so some unlucky donor human or animal would need to touch the plant first.

hilbert42 4y ago

Thanks very much for that most interesting reference. (I'm sure I'd have seen it earlier if I'd not let my sub to Science expire.) "These irritation-inducing molecules include histamine, acetylcholine, 5-hydroxytryptamine as well as formic acid and other low–molecular weight organic acids." Having been stung by bull-ants and like brethren, I can attest that as bad and as painful as these formic acid/concoction-type stings were they pail against what I experienced from Gympie-Gympie. "…none of these small molecules in the volar forearm of humans was entirely sufficient to reproduce the symptoms of a Dendrocnide sting," That is also fully consistent with my experience. What I find so interesting about this paper (in addition to my interest through experience), is that these are newly discovered toxins which seems somewhat strange given the ubiquity of Gympie-Gympie and its well-known ability to inflict excruciating pain. Presumably, this discovery will spur on further toxins research.