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pleco
SFN Addict
USA
2998 Posts |
 Posted - 01/11/2009 : 01:29:01
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Source
One of the most enduring questions is how life could have begun on Earth. Molecules that can make copies of themselves are thought to be crucial to understanding this process as they provide the basis for heritability, a critical characteristic of living systems. Now, a pair of Scripps Research Institute scientists has taken a significant step toward answering that question. The scientists have synthesized for the first time RNA enzymes that can replicate themselves without the help of any proteins or other cellular components, and the process proceeds indefinitely.
The work was published on Thursday, January 8, 2009, in Science Express, the advanced, online edition of the journal Science. |
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by Filthy
The neo-con methane machine will soon be running at full fart. |
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H. Humbert
SFN Die Hard
USA
4574 Posts |
Posted - 01/11/2009 : 02:17:08 [Permalink]
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Wow, that is frickin' amazing. Perhaps most important, natural selection began to work immediately, quickly leading to evolved replicators that the scientists didn't seed directly:
| [The researchers] mixed 12 different cross-replicating pairs, together with all of their constituent subunits, and allowed them to compete in a molecular test of survival of the fittest. Most of the time the replicating enzymes would breed true, but on occasion an enzyme would make a mistake by binding one of the subunits from one of the other replicating enzymes. When such "mutations" occurred, the resulting recombinant enzymes also were capable of sustained replication, with the most fit replicators growing in number to dominate the mixture. "To me that's actually the biggest result," says Joyce. |
I know this research will have zero affect on the views of creationists, but this is a major step toward understanding the origin of life. The god of the gaps just got a little less living space.
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"A man is his own easiest dupe, for what he wishes to be true he generally believes to be true." --Demosthenes
"The first principle is that you must not fool yourself - and you are the easiest person to fool." --Richard P. Feynman
"Face facts with dignity." --found inside a fortune cookie |
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Dr. Mabuse
Septic Fiend
Sweden
9688 Posts |
Posted - 01/11/2009 : 02:55:26 [Permalink]
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This is awsome support for the RNA-World hypothesis.
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Dr. Mabuse - "When the going gets tough, the tough get Duct-tape..."
Dr. Mabuse whisper.mp3
"Equivocation is not just a job, for a creationist it's a way of life..." Dr. Mabuse
Support American Troops in Iraq:
Send them unarmed civilians for target practice..
Collateralmurder. |
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HalfMooner
Dingaling
Philippines
15831 Posts |
Posted - 01/11/2009 : 03:07:43 [Permalink]
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Wow, wow, wow!
I call this the first synthetic life. Truly a stupendous breakthrough. I've long hoped this would finally happen in my lifetime.
Note that the very simple RNA enzymes only needed a start, then evolution improved them. In the ancient world-wide soup of enriched amino acids, something like that "start" was bound to happen within a few hundred million years. Then it was just natural selection, and horizontal transfer, making better and better (from the standpoint of replication) "organisms."
True, these RNA critters are simpler than viruses, and viruses are not life, by traditional thinking. But really that thinking is wrong. Anything that can assemble copies of itself from surrounding chemicals is life, especially if those copies sometimes are "imperfect" and capable of being evolutionarily superior.
Like the fused ape chromosomes that became human Chromosome 2, this breakthrough is a Creationism killer. For the Creos, it's all over but the shrieking, though that may go on for a very long time.
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“Biology is just physics that has begun to smell bad.” —HalfMooner
Here's a link to Moonscape News, and one to its Archive. |
| Edited by - HalfMooner on 01/11/2009 03:12:05 |
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HalfMooner
Dingaling
Philippines
15831 Posts |
 Posted - 01/11/2009 : 03:13:47 [Permalink]
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Originally posted by Dr. Mabuse
This is awsome support for the RNA-World hypothesis.
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True! But it may yet turn out that some of the other hypothesis for abiogenesis will also turn out to work. Hell, there may be many ways for life to start.
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“Biology is just physics that has begun to smell bad.” —HalfMooner
Here's a link to Moonscape News, and one to its Archive. |
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filthy
SFN Die Hard
USA
14408 Posts |
Posted - 01/11/2009 : 04:46:10 [Permalink]
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Originally posted by HalfMooner
Originally posted by Dr. Mabuse
This is awsome support for the RNA-World hypothesis.
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True! But it may yet turn out that some of the other hypothesis for abiogenesis will also turn out to work. Hell, there may be many ways for life to start.
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Someone agrees!
I've thought for years that, as in skinning a cat, there are far more ways than one to chemically create life and only one of them involves some Big, Cosmic Juju or other, and that one a lot less likely than the rest.
I hate to spend any more time than necessary at the sites of usual suspects, but the apologetics this should inspire are not to be missed.  
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"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist! 
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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 01/11/2009 : 08:58:57 [Permalink]
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Originally posted by HalfMooner
I call this the first synthetic life. |
One of the researchers was interviewed on NPR the other night, and was rather emphatic that this is not life. |
- Dave W. (Private Msg, EMail)
Evidently, I rock!
Why not question something for a change?
Visit Dave's Psoriasis Info, too. |
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Ricky
SFN Die Hard
USA
4907 Posts |
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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 01/11/2009 : 10:37:53 [Permalink]
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| Metabolism - breaking down food for energy which is then used to build necessary molecules - is typically a condition that's required before we call something "life," which is why many scientists do not consider viruses to be alive. |
- Dave W. (Private Msg, EMail)
Evidently, I rock!
Why not question something for a change?
Visit Dave's Psoriasis Info, too. |
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Hawks
SFN Regular
Canada
1383 Posts |
Posted - 01/11/2009 : 11:33:39 [Permalink]
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Originally posted by HalfMooner
Like the fused ape chromosomes that became human Chromosome 2, this breakthrough is a Creationism killer. For the Creos, it's all over but the shrieking, though that may go on for a very long time.
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I seriously doubt that the fat lady has started singning yet. The response from the ID camp to this kind of research is going to be VERY predictable. |
METHINKS IT IS LIKE A WEASEL
It's a small, off-duty czechoslovakian traffic warden! |
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filthy
SFN Die Hard
USA
14408 Posts |
Posted - 01/11/2009 : 12:24:06 [Permalink]
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Originally posted by Dave W.
Metabolism - breaking down food for energy which is then used to build necessary molecules - is typically a condition that's required before we call something "life," which is why many scientists do not consider viruses to be alive.
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True, true. But: "All journeys begin with a single step." I find this very exciting!
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"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist!
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HalfMooner
Dingaling
Philippines
15831 Posts |
Posted - 01/11/2009 : 14:03:43 [Permalink]
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Originally posted by Dave W.
Originally posted by HalfMooner
I call this the first synthetic life. |
One of the researchers was interviewed on NPR the other night, and was rather emphatic that this is not life.
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That's in the OP-lined article. Scientists generally say the same about viruses. Abbie Smith emphatically disagrees on the latter, and I'll take her word for it and expand it to these replicating molecules.
Anyway, this is an issue of scientific definitions, and those, too, evolve.
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“Biology is just physics that has begun to smell bad.” —HalfMooner
Here's a link to Moonscape News, and one to its Archive. |
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Simon
SFN Regular
USA
1992 Posts |
Posted - 01/11/2009 : 14:33:15 [Permalink]
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The definition is life is not really clear cut (which make the IDiotic argument 'life can only come from life' even MORE IDiotic) but essentially, it is a self-replicating organism that can undergo Natural selection.
Virus are not self replicating. As for these molecules, I'd not say they are either, as they still require nucleotides to be present in their medium.
These nucleotides will arise spontaneously under the right condition but, in my opinion, at a rate too low to be judge 'just regular nutrients'.
Life would be for such a molecule to produce its own nucleotides. Not impossible, in fact. |
Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.
Carl Sagan - 1996 |
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HalfMooner
Dingaling
Philippines
15831 Posts |
Posted - 01/11/2009 : 15:00:04 [Permalink]
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Originally posted by Simon
The definition is life is not really clear cut (which make the IDiotic argument 'life can only come from life' even MORE IDiotic) but essentially, it is a self-replicating organism that can undergo Natural selection.
Virus are not self replicating. As for these molecules, I'd not say they are either, as they still require nucleotides to be present in their medium.
These nucleotides will arise spontaneously under the right condition but, in my opinion, at a rate too low to be judge 'just regular nutrients'.
Life would be for such a molecule to produce its own nucleotides. Not impossible, in fact.
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Thank you. I can see that. I had wrongly assumed the new RNA enzymes created their own component nucleotides from amino acids. It does make sense that anything which is meant to simulate the modes of the first life should be able to synthesize their components from common material found in the surrounding environment, such as simple amino acids (ala Urey et al).
Maybe the next step of research would be to get that nucleotide assembly incorporated into somewhat less simple RNA enzymes. Maybe evolution itself could do the trick for the researchers.
On the other hand, the first life may indeed have slowly assembled its descendants from the rare accidental nucleotides, especially in a local environment somehow particularly prone to creating nucleotides.
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“Biology is just physics that has begun to smell bad.” —HalfMooner
Here's a link to Moonscape News, and one to its Archive. |
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Dave W.
Info Junkie
USA
26022 Posts |
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BigPapaSmurf
SFN Die Hard
3192 Posts |
Posted - 01/12/2009 : 05:52:44 [Permalink]
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| Well really there is nothing that can self replicate without input from the outside, viruses just found a differnt niche, It seems silly to me to exclude them from the 'life' category, soley because they require other creatures to replicate. On that note, can any viruses replicate inside another virus? |
"...things I have neither seen nor experienced nor heard tell of from anybody else; things, what is more, that do not in fact exist and could not ever exist at all. So my readers must not believe a word I say." -Lucian on his book True History
"...They accept such things on faith alone, without any evidence. So if a fraudulent and cunning person who knows how to take advantage of a situation comes among them, he can make himself rich in a short time." -Lucian critical of early Christians c.166 AD From his book, De Morte Peregrini |
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Scientists develop RNA that replicates itself
