Great to see this in the NYT. I'm working with Thomas (who, in addition to being a truly exceptional scientists is a really great guy) on understanding the underlying biophysics of how these disordered proteins facilitate stress protection.
Many of these proteins are intrinsically disordered proteins (IDPs), meaning they don't actually have a set 3D structure, but instead existing in a kind of 'cloud' (ensemble) of interconverting conformations. A consequence of this is that there is no 'one' representative structure, due to this conformational heterogeneity.
People used to (very reasonably) assume that 'disordered' just meant totally random, so the thought was these disordered proteins behaved like a random polymer. However, just like in folded proteins, the amino acid sequence of these IDPs has a major impact on the way these clouds of conformations behave. Happy to discuss more here or 'offline' (see my profile for contact info) - this is basically my whole PhD, so, you know, I can go more in depth...
Yes (that's the fun part!) - I should have specified that I was just interested in getting an atomistic model of one of these tardigrade proteins to play around with in an MD simulation.
The sequences have only recently been found, and the interesting proteins don't share much homology.
Check out http://kumamushi.org for a lot if technical detail in the genome. jfarlow in comments below points to one of the interesting proteins that apparently provides dna protection.
Can't help but to think about a very distant future where we use these same disordered proteins to truly freeze organic material, including ourselves. Maybe I could be dehydrated for a few thousand years on my way to another solar system no prob.
There's a cool element of this in the Three Body Problem, a sci-fi book, where aliens use dehydration to survive to disastrous conditions on their home planet. You might like the book: https://www.amazon.com/dp/B00IQO403K/
This is why tardigrades have such high radiation tolerance as well. It turns out that dehydration is incredibly damaging, especially to DNA, and the same repair/protection systems for dealing with dehydration (such as DNA repair) tend to protect against high radiation doses as well.
At least part of that protection is conferred by the DNA-binding protein Dsup [1]. So minimally the cost is 1) producing the (unique, as far as we have searched) protein, and 2) dealing with DNA which has Dsup bound to it.
There is no free lunch, but it's actually a pretty interesting protein that seems to somehow sacrificially prevent double-stranded breaks of DNA by ionized radiation. It's likely not much more than a metabolic cost - though there is some possibility that it affects some gene regulation. When Dsup was put into mammalian cells it did confer to them protection from radiation damage.
There's a feature budget only in that there's a cost/benefit restriction for every living thing. Usually the big cost is how many calories does this gene cost vs how much does this gene benefits the organism (or it's close relatives).
What's interesting about having high radiation resistance, is that I could see a cure or vaccine for cancer could be introducing (or possibly expressing) genes that cause our cells to spend a lot more calories to repair its DNA than they already do. And the skeptic in me thinks it'll probably be marketed as a diet pill :)
Or more likely you don't see those kinds of creatures because there has been no reason for evolution to select for all those abilities in one species. It's good enough to have one of them.
But that says nothing as to whether genetic engineering could produce such creatures.
Just about the coolest little critters on Earth! They're cute, they can survive just about anything reasonably thrown their way from hard vacuum to radiation, and now this. It makes me happy to know that regardless of how badly we as a species screw up ourselves or the biosphere, these little tardigrades won't even notice.
I did miss it! Thanks, this made my day. There was a movie from the late 80's, early 90's... and I remember a pimp with platform shoes that were also an aquarium. This... is better.
You made my day in return when I viewed your list of submitted stories. So much cool stuff!
(And another sign HN needs to step up its submission/upvoting algorithms/UX. I do think so many HN-worthy stories get lost each day just because of this.)
Oh no, if you were exposed to a naked source of the type used to test the limits of organisms like tardigrades... you'd just die. Really, really, really quickly.
That's what the article is about; when they dry out, they produce an irregular protein which essentially stiffens and preserves the cells while protecting them from environmental damage. When they are rehydrated, the protein dissolves and the cells resume their normal functions.
It's pretty cool, and could indeed lead the way to hibernative naptosis.
We have some cool stuff coming along...