Is There a Connection Between Life's Origin, Geothermal Vents, Cancer, and Aging? (quantamagazine.org) 59
Long-time Slashdot reader Beeftopia writes:
All living cells power themselves by coaxing protons from one side of a membrane to the other. A place where this occurs naturally outside of cells are alkaline hydrothermal vents on the deep seafloor, inside highly porous rock formations that are almost like mineralized sponges. "Carbon and energy metabolism are driven by proton gradients, exactly what the vents provided for free," wrote biochemist Nick Lane. In Lane's view, metabolism came first, and genetic information emerged naturally from it rather than the other way around.
Quanta magazine asks Lane the big question: How did these first proto-cells become independent from the proton gradients they got for free in the hydrothermal vents? LANE: We've shown that theoretically, if you introduce random sequences of RNA and assume that the nucleotides in there can polymerize, you get little chains of nucleotides. Let's say seven or eight random letters long, with no information encoded in there whatsoever.... [H]ydrophobic amino acids are more likely to interact with hydrophobic bases. So you have a random sequence of RNA that generates a nonrandom peptide. And that nonrandom peptide could by chance have some function in a growing proto-cell. It could make the cell grow better or grow worse; it could help the RNA replicate itself; it could bind to cofactors. Then you have selection for that peptide and the RNA sequence that gave rise to it.
Although it's a very rudimentary system, this means we've just entered the world of genes, information and natural selection.
Quanta summarizes Lane's next idea: that these vent environments "favored the beginnings of what we call the Krebs cycle, the metabolic process that derives energy from carbohydrates, fats and proteins." Lane himself has said that metabolism "conjures genes into existence."
But if genes are conjured into existence by metabolism, then what else might be true? Lane ultimately concludes that cancer may be a metabolic disease rather than a "genomic" one: LANE: About 10 years ago, the cancer community was amazed by the discovery that in some cancers, mutations can lead to parts of the Krebs cycle running backward. It came as quite a shock because the Krebs cycle is usually taught as only spinning forward to generate energy. But it turns out that while a cancer cell does need energy, what it really needs even more is carbon-based building blocks for growth. So the whole field of oncology began to see this reversal of the Krebs cycle as a kind of metabolic rewiring that helps cancer cells grow....
[C]ancers aren't caused simply by some genetically deterministic mutation that forces cells to go on growing without stopping. Metabolism is important too, for providing a permissive environment for growth. Growth comes before genes in this sense.
Or, as Slashdot reader Beeftopia puts it, "In Lane's view, metabolism came first, and genetic information emerged naturally from it rather than the other way around. Lane believes that the implications of this reversal touch almost every big mystery in biology, including the nature of cancer and aging."
Quanta magazine asks Lane the big question: How did these first proto-cells become independent from the proton gradients they got for free in the hydrothermal vents? LANE: We've shown that theoretically, if you introduce random sequences of RNA and assume that the nucleotides in there can polymerize, you get little chains of nucleotides. Let's say seven or eight random letters long, with no information encoded in there whatsoever.... [H]ydrophobic amino acids are more likely to interact with hydrophobic bases. So you have a random sequence of RNA that generates a nonrandom peptide. And that nonrandom peptide could by chance have some function in a growing proto-cell. It could make the cell grow better or grow worse; it could help the RNA replicate itself; it could bind to cofactors. Then you have selection for that peptide and the RNA sequence that gave rise to it.
Although it's a very rudimentary system, this means we've just entered the world of genes, information and natural selection.
Quanta summarizes Lane's next idea: that these vent environments "favored the beginnings of what we call the Krebs cycle, the metabolic process that derives energy from carbohydrates, fats and proteins." Lane himself has said that metabolism "conjures genes into existence."
But if genes are conjured into existence by metabolism, then what else might be true? Lane ultimately concludes that cancer may be a metabolic disease rather than a "genomic" one: LANE: About 10 years ago, the cancer community was amazed by the discovery that in some cancers, mutations can lead to parts of the Krebs cycle running backward. It came as quite a shock because the Krebs cycle is usually taught as only spinning forward to generate energy. But it turns out that while a cancer cell does need energy, what it really needs even more is carbon-based building blocks for growth. So the whole field of oncology began to see this reversal of the Krebs cycle as a kind of metabolic rewiring that helps cancer cells grow....
[C]ancers aren't caused simply by some genetically deterministic mutation that forces cells to go on growing without stopping. Metabolism is important too, for providing a permissive environment for growth. Growth comes before genes in this sense.
Or, as Slashdot reader Beeftopia puts it, "In Lane's view, metabolism came first, and genetic information emerged naturally from it rather than the other way around. Lane believes that the implications of this reversal touch almost every big mystery in biology, including the nature of cancer and aging."
They all have (Score:2)
Got nuttin.
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Cue panspermia poster... (Score:3, Interesting)
...saying that life arose elsewhere in the universe and rode on a rock after being blasted off its home world with the fragile organics somehow surving that and not degrading after a few billion years in space before it entered earths atmosphere and got heated to a few thousand degrees before it hit the surface at multimach speed yet was still viable.
And hoping no one notices the handwaving away of the issue at hand of how life chemistry could have arisen on the planet it arose on.
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I don't like that one as much as the poster for Pan's Labyrinth [wikipedia.org] ...
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We already know that spores could survive such a journey.
That you're pooh-poohing it is fairly well hilarious.
Thanks for that. We could all use a laugh.
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"We already know that spores could survive such a journey."
You'll be able to provide some evidence for that then wont you.
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Learn to internet, noob. I'm not here to hold your dick for you. This is well-known, so it's trivial to find citations; if you actually wanted one you could have just copy and pasted what I said into google.
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Learn to internet, noob. I'm not here to hold your dick for you. This is well-known, so it's trivial to find citations; if you actually wanted one you could have just copy and pasted what I said into google.
For my own amusement, I tried that.
https://www.google.com/search?... [google.com]
All of the hits referred to interplanetary distances (most of them specifically travel between Earth and Mars). Not interstellar.
If you're talking about sharing life between Earth and Mars, OK. If you're talking another star, no.
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Complete with references.
https://en.wikipedia.org/wiki/... [wikipedia.org]
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No, I asked for proof that they can survive in space for BILLIONS of years and survive being blasted off a planet and temps of a few thousand degrees. Not proof that they can last a few years in low earth orbit, we all know that.
Have another go.
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It's like they think it's synonymous to the debris that gently floats down to the oceans' floors.
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The inside of meteorites don't heat up in the couple of minutes of reentry and small ones hit fairly gently judging by the people that have been hit by them or near misses.
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More to the point, it's not an argument that this isn't how it got started. Whether even a localized version of panspermia is indicated depends on just how unlikely this process is to get started. It does, however, seem quite likely that all surviving life on Earth originated from the same source. (Ribosomes and other basic machinery of life seem to have just one source.)
This doesn't mean life didn't start on, say, Europa or Mars and get blasted off as a metorite and end up on Earth before taking over.
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We already know that spores could survive such a journey.
Without knowing what "such a journey" you are thinking about, can't evaluate that.
If "such a journey" means drifting between stars and waiting for a chance encounter with a start with a planetary system: no. Cosmic radiation would make a spore nonviable over the time span required.
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There are missions planned (or at least conceptualized) [wikipedia.org].
The motivating factor behind the theory is that the earth is not old enough (as Crick pointed out) for the DNA-to-protein mechanisms to form from random mutations (or chance). I don't have the ability to evaluate Crick's analysis, but it seems to have convinced other scientists.
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... I don't have the ability to evaluate Crick's analysis, but it seems to have convinced other scientists.
Speaking for other scientists, he has definitely not convinced most of them.
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Ok? Most scientists aren't qualified to comment on the topic.
There's not enough evidence to dismiss the hypothesis (which you seem to want for some reason).
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Ok? Most scientists aren't qualified to comment on the topic.
True, I suppose, but I actually do go to astrobiology conferences, and know the scientists who are qualified. Most of them are not convinced.
There's not enough evidence to dismiss the hypothesis (which you seem to want for some reason).
You slide so smoothly from "most scientists are convinced" to "there's not enough evidence to dismiss it."
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You slide so smoothly from "most scientists are convinced" to "there's not enough evidence to dismiss it."
Ah, now you are trying to play fast and smooth with words.
Be intellectually honest. I never said "most scientists are convinced."
Verbatim [Re:Cue panspermia poster...] (Score:2)
Ah, now you are trying to play fast and smooth with words. Be intellectually honest. I never said "most scientists are convinced."
Your words:
"I don't have the ability to evaluate Crick's analysis, but it seems to have convinced other scientists."
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Yeah.
"it seems to have convinced other scientists."
" it seems to have convinced most other scientists."
Can you see the difference?
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Now who is "trying to play fast and smooth with words"?
Bye.
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Learn to read.
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Re:Cue panspermia poster... (Score:5, Informative)
I don't see panspermia as being much of a problem. Panspermia does NOT predict origin on another planet, it predicts origin in space. And we know organics form in space. We also know that comets and asteroids accumulated material in the early days of the solar system from the accretion disk. They still are, at a slower rate. So it's not handwaving to say that the body could have accumulated enough extra material to shield the organics from re-entry. After all, meteorites that land are typically COLD, not hot.
I don't think it's correct, you don't need organics from space to explain organics on Earth, but your argument is so utterly wrong about what panspermia actually predicts that it is worth correcting even though I agree with the conclusion that the chemistry could easily have arisen on Earth.
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"And we know organics form in space"
Want to have a guess at the average density of gas clouds in space? Most of the molecules and atoms barely interact. Good luck getting any chemistry beyond basic starter moleculres created in those conditions. If they exist in those clouds its because they've been created in a supernova.
"After all, meteorites that land are typically COLD, not hot."
Err yes, after they've got exceedingly hot on entry they then cool down.
Astrobiology comments [Re:Cue panspermia poster... (Score:1)
"And we know organics form in space"
Want to have a guess at the average density of gas clouds in space? Most of the molecules and atoms barely interact. Good luck getting any chemistry beyond basic starter moleculres created in those conditions.
You may have different ideas of what "in space" means. When we look at pretty much everything outward roughly of Saturn, we see brownish-red goo, known as "tholins [planetary.org]", which are tangled long-chain organics, primarily hydrocarbons, with admixtures of other stuff like sulfur and nitrogen. These are, for example, the reddish splotches on Pluto and Charon; they're why the atmosphere of Titan is brownish. Organics turn out to plentiful in space.
How do we get from tholins (as well as random amino acids, also foun
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"Organics turn out to plentiful in space."
ITYM plentiful on various planets.
"And where does that happen?"
On the surface thanks to a supply of hydrocarbons, water ice and solar radiation.
"report that the actual rock remains cold"
Small rocks will slow down to terminal velocity long before they hit the ground. Watch the Baumgartner video of his space jump and see how fast he slows down when he hits the lower levels of the atmosphere. Then they have a few minutes of falling through freezing air to cool off.
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They're cold to the touch after landing, those couple of minutes of reentry only heat up the our surface.
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Panspermia does NOT predict origin on another planet, it predicts origin in space.
you mean "Pseudo-panspermia (sometimes called soft panspermia, molecular panspermia or quasi-panspermia)".
https://en.wikipedia.org/wiki/... [wikipedia.org]
actual panspermia isn't concerned with the origin of life at all, just its occurrence and distribution.
imo panspermia made sense until last century as an interesting myth. since the discovery of those vents the theory has become pretty irrelevant. it doesn't predict anything useful at all. yes, building blocks can form and exist in space. on planets too. and yes, all pla
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Well, depending on the version (there are several, and I refuse to anoint one particular one as "the true panspermia"), it could predict life's origin in space. Which I find unlikely. That organics exist in space is true, but so far the only evidence is for very simple organics. (OTOH, what evidence would you expect to find given the tools that we are searching with?) But if you adopt a version that predicts the space-based origin of cellular life, it would also predict that things like ribosomes would
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After the outer surface has vaporized by reentry.
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> Panspermia does NOT predict origin on another planet, it predicts origin in space.
If that's the case, what's the theory for planet-to-planet transfer called?
The bottom line is nobody knows (yet) where Earth life originated from. Mars was in better shape to produce life early in the solar system, so is a good candidate. Earth was too volcanic and volatile early.
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I don't understand why people go in that direction of thought in the first place. Like it's that life is way too improbably to have developed on this planet, so maybe it developed on a different planet where it is.. also.. improbable..? And that leads towards "I'm not saying it's aliens, but..." which leads towards "I'm not saying it's a deity, but..."
Not sure what's wrong with the idea that life is a perfectly normal and natural thing for this planet.
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The basic idea here is that, if it's possible for single cellular life to migrate between star systems through "fluke" events on timescales of hundreds of millions of years, you have orders of magnitude more planets out there where an unlikely "start of life" event could happen.
If the number of extra planets available in the galaxy times the probability/rate of transmission is enough higher than the rate of native life generation, most planets with life would get it through seeding rather than developing it
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I don't know about panspermia, but the process this guy is describing involves a lot of hand waving. At best, he's managed to describe one small part of the puzzle, while ignoring the rest. At worst, he's completely off his rocker. Saying "coaxing protons from one side to the other" is not much more than saying "chemical reactions happen."
The motivating idea behind modern (directed) panspermia [wikipedia.org] is that (as Crick pointed out) it would take too long, considering the age of the earth, for the chemical reactions
sounds plausible (Score:3)
https://www.quantamagazine.org... [quantamagazine.org]
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He's currently running computer models to see if they support his theory with a small t. His next step is to do actual experiments.
No (Score:3)
It would violate Betteridge's law of headlines.
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Yeah, there's a number of red flags ("The renegade scientist who also has written a book on his theory" trope, for example). But that said, it's still an interesting theory, when you get into the details.
* The basic aspects of something like the Krebs cycle can demonstrably run in reverse in mockup geothermal vent conditions - converting protons and CO2 into simple energy-rich organic molecules, setting up the potential for cascades of chemical reactions.
* These organic molecules can have all sorts of impa
A very viable argument (Score:5, Insightful)
It would mean that cancer is NOT a modern disease (which we already knew, but there are still holdouts who argue otherwise) but rather fundamental to how cells operate. It also means that attacking cancers through metabolism would seem to be the correct approach, even if we've not been doing it quite right so far.
If the reverse cycle theory is correct, is the reverse cycle employed by healthy cells much? Is there a way to target such an operation directly?
However, I'm also very interested in the cellular origins idea. It certainly agrees with what is known and would fill in a lot of the gaps. Understanding the origins of cells would likely lead to all kinds of interesting things, especially if cells today are really mostly about manufacturing the same processes and environment as cells originally formed in.
Re:A very viable argument (Score:4, Informative)
Pathogens Hijack Host Cell Metabolism:Intracellular Infection as a Driver of the Warburg Effect in Cancer and Other Chronic Inflammatory Conditions
Proal, A. D., & VanElzakker, M. B. (2020). Pathogens hijack host cell metabolism: intracellular infection as a driver of the Warburg effect in cancer and other chronic inflammatory conditions. Immunometabolism, 3(1).
The Warburg effect refers to a metabolic state in which cells preferentially use aerobic glycolysis rather than oxidative phosphorylation to generate ATP and macromolecules. A number of chronic inflammatory conditions are characterized by host cells that adopt a sustained, pathological Warburg-like metabolism.
In cancer, previously healthy cells shift into a Warburg state centered on rapid energy production and increased cell proliferation that drives tumor formation. Macrophage in atherosclerotic plaque and in sarcoidosis granuloma can also harbor a Warburg-like phenotype that promotes an inflammatory milieu. The question of why host cells in patients with cancer and other chronic inflammatory conditions adapt a pathological Warburg-like metabolism is a matter of debate. This review/hypothesis piece explores how intracellular infection can contribute to this Warburg metabolism or related pathological metabolic states. We detail molecular mechanisms by which viral,bacterial, and protozoan intracellular pathogens can induce, or contribute to, a Warburg-like metabolism in infected host cells in order to meet theirown replication and nutritional needs. We also discuss how host defense towards infection may impact cellular metabolic changes. We then provide examples of how many of these same intracellular pathogens have been identified in tumors,atherosclerotic lesions, granuloma, and other tissues containing cells with a Warburg or altered metabolism. Last,we examine further trends associated with infection and host cell metabolism, including how pathogen-driven hi jacking of host cell lipid metabolism can support viral, bacterial, and parasite survival and replication.
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Also
Copy number of latent viruses, oncogenicity, and the microcompetition model
Hanan Polansky and Hava Schwab
Oncotarget, 2018, Vol. 9, (No. 60), pp: 31568-31569
https://pdfs.semanticscholar.o... [semanticscholar.org]
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IIUC, it's currently one of the favored theories about how life got started. (It's certainly been around for decades.) This seems to add a bit more detail to the theory, but other theories also have occasionally had more detail added.
Of the existing (major) theories, this one seems to be the easiest to properly develop. Which doesn't mean it's correct. Even if it turns out that the entire theory can be made to work, that won't constitute proof that that's the way it happened. (That assertion is probabl
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Let's say that it is correct. Then one implication of that is that deep ocean smokestacks can be induced to act like living cells, since that is essentially what is being proposed. The more complex that induction is, the less likely it is to have occurred naturally. If it can't be done at all, then obviously this route is impossible. It also tells you what, if anything, needed to have come from an outside source, and how much of that what.
(We now know much more about the early Earth atmosphere, so we've a m
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IIUC, it implies that small tubules within deep ocean smokestacks can be induced to act like living cells, for rather limited meanings of "act like". And without much in the way of a claim to efficiency.
Also, when the mess of stuff (comets, eroded rocks, etc.) are combined they're likely to react together, so just knowing the original proportions isn't going to answer the questions of "what was around in the environment to start with", though it gives you a sort of starting point for figuring that out. Va
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Well...not precisely. Just because this is how cancers get started wouldn't mean this is the only/best way to attack them. I, personally, suspect that there's a problem with autoimmune diseases which causes the immune system to be weak at handling cancers, and that fine-tuning the immune system could be the best approach.
Re: A very viable argument (Score:1)
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It also means that attacking cancers through metabolism would seem to be the correct approach, even if we've not been doing it quite right so far.
A lot of chemotherapy relies on the metabolism of the cancer to kill the cancer.
I knew those geothermal vents were a bad idea (Score:2)
A (my) simpleton's take (Score:2)
Sounds like this theoretically corroborates what a lot of people have found out about cancer in my lifetime, contrary to the 'best advice' of the medical establishment: if you starve a cancer of the unhealthy fuel it needs to thrive, you can kick it into remission or even "fully recover", by eating nutritious, low-carb foods (as well as various other fortifications).
I'm curious how canibis impacts this process in mammals.
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