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Tree of Life Gets Stung by Jellyfish

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In yet another unexpected finding from the world of comparative genomics a gene that gives a jellyfish its sting is found all over the place. All sorts of explanations are flung at it. Horizontal gene transfer, vertical gene transfer, and convergent evolution were all run up the flagpole to see which garners more salutes. 🙄

Click the link below for a nice jellyfish picture and hotlinks in the references or just read the text below the fold.

How the jellyfish got its sting

From a bacterium, surprisingly.
Amber Dance

Jellyfish may owe thanks to a humble bacterium for their ability to sting prey. Scientists have found that one of the genes necessary for them to sting is similar to a gene in bacteria, suggesting the ancestors of jellyfish picked up the gene from microbes. The research is published this week in Current Biology[1].

“The result was a great surprise,” says developmental biologist Nicolas Rabet of the Pierre and Marie Curie University in Paris, France, who led the team.

“[This kind of] horizontal gene transfer is often neglected, and could sometimes be more important than we thought.” Unlike vertical gene transfer from parent to offspring, the horizontal variety happens between organisms, or even between different species. Common in microbes, it has only been described a few times in animals. Japanese beetles have picked up sequences from a parasitic bacterium[2] and microscopic aquatic creatures called bdelloid rotifers have collected genes from bacteria, fungi and plants[3].

The gene in question codes for a subunit of poly-gamma-glutamate (PGA) synthase – PGA itself is a major component of stinging cells[4]. The gene appears in all known genomes of creatures from the phylum cnidaria, which includes jellyfish, anemones and corals.

By collecting positive ions, PGA allows the cells to regulate their osmotic pressure; a sudden change in that pressure launches a poisonous barb. In bacteria, the same compound can form a protective capsule. It also gives the fermented Japanese food natto its stringy texture and pungent aroma.[5]

Using phylogenetic analysis, Rabet and his colleagues found that the cnidarian gene fits well into the bacterial family tree. They also showed that the gene turns on in at least one jellyfish, Clytia hemisphaerica. The same gene pops up in certain sponges, worms and fungi, suggesting it jumped between species more than once, the scientists say. It is not yet clear how the transfer might have occurred, or why this particular gene would be so well-travelled.

Vertical or horizontal?

“I think the author’s interpretation is probably correct,” says Michael Syvanen, who studies comparative genomics at the University of California, Davis. However, he is not convinced that other possibilites can be ruled out.

“There are other explanations for the incongruencies they see in the tree,” agrees Casey Dunn, an evolutionary biologist who studies phylogenetic problems at Brown University in Providence, Rhode Island.

For instance, the gene could be vertically transferred from a distant progenitor, before being lost from some organisms. Or, it may be possible that more than one animal independently evolved the gene; such sequence conversion is not unheard of, Dunn says. “At the end of the day, it will probably take far more data to paint a conclusive picture of what’s happening.”

Rabet responds that since the PGA synthase gene is approximately 1000 bases long, it is statistically unlikely to be the product of multiple distinct genes converging on the same sequence

And if the gene was lost from all but the cnidarians and a few other animals, it must have disappeared from all related organisms. “It’s possible, but we need to imagine a lot of lost genes,” he says.

Scientists are finding that horizontal gene transfer, once thought to be the domain of single-celled critters, is not uncommon in the animal world, says Syvanen. “Horizontal gene transfer with the animals is going to turn out to be more widespread than anybody believes now. When that realization comes down, it will definitely change the way people think about evolution.”

*
References
1. Denker, E., Bapteste, E., Le Guyader, H., Manuel, M. & Rabet, N. Current Biology 18, R858-R859 (2008). | Article | PubMed | ChemPort |
2. Kondo, N., Nikoh, N., Ijichi, N., Shimada, M., & Fukastsu, T. Proc. Natl Acad. Sci. 99, 14280-14285 (2002). | Article | PubMed | ChemPort |
3. Gladyshev, E. A., Meselson, M. & Arkhipova, I. R. Science 320, 1210-1213 (2008). | Article | PubMed | ChemPort |
4. Weber, J. J. Biol. Chem. 265, 9664-9669 (1990). | PubMed | ISI | ChemPort |
5. Candela, T. & Fouet, A. Mol. Microbiol. 60, 1091-1098 (2006). | Article | PubMed | ChemPort |

Comments
While genes may be a factor in the whole jellyfish's ability to sting, it still doesn't prove how natural selection made it possible for them to do so. If this was a random, wouldn't there have been some jellyfish that didn't have any ability to sting at all?JoeMamma77
October 2, 2008
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Domoman, I agree. I first started thinking about how the whole naturalistic tale was like a fairy tale many years ago when reading about cosmology. The tale starts before the big bang and extends all the way to the present (including abiogenesis and several aspects of evolution). Despite the fact that we know that technology, meaningful specified codes/languages only arise from intelligent design, their tale invokes the mysterious forces of time, warm ponds, cold comets, singularities, dark matter, dark energy, more recently dark flow, multiverses, undetectable strings, and so on and so forth. The mental gyrations that they need to invoke just to make their just so tale seem even remotely possible are astounding. It seems to me, if their theories don't seem to work, they just invent some imaginary force, or imaginary sets of conditions, that can't be detected and never falsified. If they are lucky enough to falsify something, they just invent something new that is unmeasurable to plug the holes in their theories.parapraxis
October 1, 2008
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Parapraxis, I was reading a description of how life started, from non-life to life, the other day. I thought to myself: this sounds just like a fairy tale. They have all these detailed descriptions of how it happened yet they lack two things: any proof in the labs that it could happen, and any proof that it happened in the past. Most evolutionists also conveniently forget the fact that ANY and ALL forms of meaningful, specified codes/languages arise from intelligence. We know of literally no other way of creating these codes/languages aside from intelligence Yet when we find it in organisms they still try to explain it through random processes or through repetitive laws of nature.Domoman
October 1, 2008
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Wonderer, I think the Darwinian tales sound exactly like fairy tales. In fact, I've written (so far) an 11 part series on naturalistic fairy tales. The Darwinists don't like it, but such is life. Naturalistic Fairy Talesparapraxis
September 30, 2008
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At what point will these Darwinian tales begin to sound exactly like fairytales? Thanks Patrick for illustrating how an common Designer would achieve the same end.the wonderer
September 30, 2008
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My take on this is that the origins of life's systems cannot ever be fully explained. I call it the "Argument from Impossibility". I've outlined it here: http://chuckydarwin.newsvine.com/_news/2008/09/25/1912604-the-argument-from-impossibilityChucky Darwin
September 30, 2008
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Jellyfish may owe...suggesting the ancestors of jellyfish picked up the gene from microbes. Ah yes, more mayhap and suggestion. We can ignore the facts now, ignore the data, and go on with the suggestion-to-assumption that evolution is responsible for this. Soon the sheer volume of opinionated papers will suffice as proof the suggestion is true. Horizontal gene transfer with the animals is going to turn out to be more widespread than anybody believes now. And if it doesn't turn out to be true textbooks will be printed as if it were because [queue robotic brainwashed monotone] Evolution is true...is true...is true...WHACK Evolution is true because truth is Evolution and Evolution is true. When that realization comes down, it will definitely change the way people think about evolution.” No it won't. When that realization comes down --as official dogma pounded hard from the university pulpits, it will be seen by those without Darwin's wooly beard over the eyes as hemming & hawing and excuse making for something that was only suggested to have happened. A stinger is DESIGNED for a purpose, for defense and/or paralyzation of prey. Blind-dead-dumb-mindless chance cannot account for it in any way.beancan5000
September 30, 2008
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My first thought upon reading the headline was: "Is it constructively functional in both bacterium and jellyfish?" But after that initial assertion it became increasingly clear they cannot tell if the bacterium received the gene from the jellyfish or the other way around (their preferred interpretation). Or if all instances of the usage of this gene are front-loaded. While these people would be unlikely to consider that interpretation, what they may do is posit that the vast majority of genes were generated early in life's history. Not very different from the ID scenario except for the source of the information.
It is not yet clear how the transfer might have occurred, or why this particular gene would be so well-travelled.
That's one thing that's always bugged me about HGT research. The focus always seems to be on "merely" a successful transfer. NOT on how the receiving organism/plant/animal/whatever will somehow transform this "new gene" into a constructively functional system or component that gives a survival advantage. One thing is clear, that information is in the regulation, not the gene itself, since the creatures using this gene are using it for a wide variety of functionality.
Rabet responds that since the PGA synthase gene is approximately 1000 bases long, it is statistically unlikely to be the product of multiple distinct genes converging on the same sequence
Heh. If these 1000 bases compose an IC core I'd say "statistically unlikely" is an understatement...that's 2000 informational bits!
Scientists are finding that horizontal gene transfer, once thought to be the domain of single-celled critters, is not uncommon in the animal world, says Syvanen.
In that regard: The Edge of HGT Darwin's Legacy HGT from GMOs Does Happen
“Horizontal gene transfer with the animals is going to turn out to be more widespread than anybody believes now. When that realization comes down, it will definitely change the way people think about evolution.”
Now I've thought for years that a smart Designer--whether it be a Designer reuse or front-loading scenario--would incorporate transport mechanisms to share information in a network-like fashion. Why? So everything can respond relatively quickly to an environment that can change rapidly. This would be Directed HGT, in contrast to Darwinist's preference for Undirected/Non-Foresighted HGT. The problem is, if such a system as Directed HGT were to deteriorate (genetic entropy), and the organisms responsible for transportation simplified until they were survival-oriented replicators, thus becoming Undirected, then such a system could cause chaos (cancers, toxic reactions, etc. as noted in research). My hope is that if such a purposeful system was intended it did not rely on serendipity and thus we might hope to discover functional remnants.Patrick
September 30, 2008
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lol @ steveO. That is hilarious.tragicmishap
September 30, 2008
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Our IT group has been having fun with an evolutionary biologist's PC. As I'm sure most are aware, a patch is a small piece of carefully designed software that can modify a computer program to include fixes and updates. These patches are being applied surreptitiously. He has now come up with a theory that random lateral transfer of code between different binary executables on his PC are resulting in his favourite program running faster and acquiring brand new functionality. Chance be praised ! :-) ;-)steveO
September 30, 2008
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gpuccio re; great surprise If one has an underlying theory of biology that's wrong one can expect a great many surprises. If one has an underlying theory of biology that's correct there won't be any great surprises. Nothing has surprised me since I figured out a few years ago that a front-loaded genome explained the facts far better than chance & necessity. As long as biology keeps clinging to the failed paradigm of chance & necessity driving all of organic evolution they're in for a lot more surprises as comparative genomics gets a larger and larger catalog of fully sequenced organisms to work with.DaveScot
September 30, 2008
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Combinatorial logic (CL)- Just read Sean Carroll's "Endless Forms..." (or was it in "Making of the Fittest"?) With CL one gene can be used in several differing capacities. However the issue now is how the heck can non-telic processes come up with combinatorial logic? The answer? "It just happened and once it happened it was good so it was kept."Joseph
September 30, 2008
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"The result was a great surprise". Again. Once again. Why am I no more surprised of surprises? By the way, we should really take notice and make a list. And evaluate the rate of surprises in the biologic world...gpuccio
September 30, 2008
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What'd they decide? Isn't it all about consensus these days?jjcassidy
September 29, 2008
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Van, I think Evolutionists have really run into a stand still on the idea that genes really make the difference between animals shape, form, and behavior. I just read a part of The Case for a Creator by Lee Strobel and it talked about genes. Apparently certain rats and certain fruit flies have identical, or VERY similar genes, for their eyes. So much in fact that if you were to swap a rat's eye gene for a fly's eye gene they would both still grow their regular eyes. A rat would grow his regular eyes and a fly would still grow compound eyes. Genes really don't seem to be that effective in changing animals identities.Domoman
September 29, 2008
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"Jellyfish may owe thanks to a humble bacterium for their ability to sting prey. Scientists have found that one of the genes necessary for them to sting is similar to a gene in bacteria, suggesting the ancestors of jellyfish picked up the gene from microbes" so, uh...just a couple quick questions here: 1) why don't bacteria have the ability to sting?...Same gene. And 2) if the gene doesn't determine the trait then why should we believe Darwinism, which says changes in genes over time equate to changes in bodies over time? If bodies change without genes changing, then what the heck?...how did genomes get built up?van
September 29, 2008
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