[ExI] why tardigrades are indistructible

[William Flynn Wallace]

 Now I just figure out how to do the other two letters and I can survive
hell.



spike


The sound of one hand clapping - cl

Now just make that a g and you're all set


bill w

On Tue, Nov 19, 2019 at 8:50 AM spike jones via extropy-chat <
extropy-chat at lists.extropy.org> wrote:

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> Cool article.  This claims the tardigrade can preserve itself indefinitely
> because it can turn itself into glass.
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> If so, this is really cool.  I am already 60% of the way to being able to
> turn myself into glass: I am already good at making an ass of myself.  Now
> I just figure out how to do the other two letters and I can survive hell.
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> spike
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> Scientists finally figure out why the water bear is nearly indestructible
>
> Freeze it, boil it, or expose it to radiation. The water bear shrugs it
> off. Now we know why.
>   PHILIP PERRY <https://bigthink.com/u/philip-perry>
>
> 17 March, 2017
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> Medically accurate model of a tardigrade or water bear.
>
> The tardigrade
> <https://www.nytimes.com/2017/03/16/science/tardigrades-water-bears-dried-out.html>,
> also known as the moss piglet or water bear, is a bizarre, microscopic
> creature that looks like something out of a Disney nightmare scene: strange
> but not particularly threatening. The pudgy, eight-legged, water-borne
> creature appears to be perpetually puckering. It's the farthest thing from
> what you'd expect an unstoppable organism to look like.
>
> Yet, water bears can withstand even the vacuum of space
> <https://www.wired.com/2017/03/secret-crazy-tough-water-bear-finally-revealed/>,
> as one experiment showed. A sort of microscopic Rasputin, tardigrades have
> be frozen, boiled, exposed to extreme doses of radiation, and remarkably
> still survive. How they do this has been a mystery to science, until now.
>
> Being a water-borne creature, scientists in this experiment examined how
> it survived desiccation, or being completely dried out. When it senses an
> oncoming dry period, the critter brings its head and limbs into its
> exoskeleton, making itself into a tiny ball. It'll stay that way, unmoving,
> until it's reintroduced into water.
>
> It's this amazing ability that piqued Thomas Boothby's interest. He's a
> researcher at the University of North Carolina, Chapel Hill. Boothby told
> *The* *New York Times*, “They can remain like that in a dry state for
> years, even decades, and when you put them back in water, they revive
> within hours." After that, “They are running around again, they are eating,
> they are reproducing like nothing happened."
>
> Originally, it was thought that the water bear employed a sugar called
> trehalose to shield its cells from damage. Brine shrimp (sea monkeys) and
> nematode worms use this sugar to protect against desiccation, through a
> process called anhydrobiosis. Those organisms produce enough of the sugar
> to make it 20% of their body weight.
>
>   TOP ARTICLES3/5READ MOREScientists create precursor to life inthermal
> vent experiment
>
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> Not the water bear. Trehalose only takes up about 2% of its entire system,
> when it's in stasis. Though employing a sugar to preserve one's body sounds
> strange, the newly discovered process that the water bear goes through is
> even more bizarre. It turns itself into glass.
>
> In this study, tardigrades were placed into a drying-out chamber, which
> mimicked conditions the organisms would encounter in a disappearing pond.
> As the water bears underwent anhydrobiosis, scientists examined what genes
> were activated. These genes produced a certain protein, which they named
> tardigrade-specific intrinsically disordered proteins (TDPs).
>
> When the genes which produce TDPs were blocked, the water bears died. “If
> you take those genes and put them into organisms like bacteria and yeast,
> which normally do not have these proteins, they actually become much more
> desiccation-tolerant," Boothby said.
>
> It's when the drying out process begins that such genes are activated,
> flooding the water bear's system with the protective protein. The process
> occurs in much the same way as trehalose preserves sea monkeys, according
> to Boothby. This is an example of convergent evolution
> <https://www.sciencedaily.com/terms/convergent_evolution.htm>, when two
> unrelated organisms develop the same trait for survival.
>
> Usually, proteins are formed in orderly, 3D chains of amino acids. But
> TDPs operate differently, in a kind of random, somewhat disorganized
> manner. Dr. Boothby said, “It's a really interesting question about how a
> protein without a defined three-dimensional structure can actually carry
> out its function in a cell." Another question, is this protein used by any
> other organisms?
>
> When desiccation begins and TDP is activated, it engages a process known
> as vitrification <http://www.dictionary.com/browse/vitrify>. Boothby
> said, “The glass is coating the molecules inside of the tardigrade cells,
> keeping them intact." From there, it goes into a form of stasis until it
> detects water. When that occurs, the protein is dissolved into the liquid
> and the tardigrade is revived.
>
> There could be some practical uses to this discovery. For instance in
> medicine, vaccines often require refrigeration. But in the developing
> world, it isn't always available, which makes delivering vaccines to
> vulnerable, rural communities difficult.
>
> Dr. Boothby believes that we may be able to use TDP to sort of freeze-dry
> vaccines or medications, for easy storage and transport. What about putting
> humans in stasis for space travel or when they have terminal diseases, to
> await a cure? No word on that, yet. Scientists have years of research ahead
> of them already, just to understand the inner-workings of TDP.
>
> Some believe tardigrades may have “alien" DNA. To find out more, click
> here:
>
>
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