For Peter: Protein Synthesis
This process takes place in your body every second of the day, and it takes place with utter and unerring fidelity across thousands of discrete chemical steps.
Every single second of the day.
And here's your "You really didn't think that through, did you?" explanation of the day:
A U.S. study of transfer RNA is challenging long-held theories concerning the evolutionary history of protein synthesis.
University of Illinois researchers report the dual functions of transfer RNA, or tRNA — a molecule that delivers amino acids to the protein-building machinery of the cell — apparently originated independently.
“Structure is highly conserved, capturing information that is evolutionarily deep,” said Professor Gustavo Caetano-Anolles, who led the study. “It was only logical to focus on transfer RNA, a molecule that is believed to be very ancient and is truly central to the entire protein synthesis machinery.”
During protein synthesis, tRNA’s dual function is reflected in its unique L-shaped structure, the scientists said. One end of the molecule decodes messenger RNA — a molecule that carries instructions for the sequence of amino acids in a protein — while the other transfers a specific amino acid to the growing protein chain.
Previously scientists assumed the two functional domains of tRNA had evolved together. But Caetano-Anolles and researcher Feng-Jie Sun determined the two functions have different evolutionary histories, which suggests they were acquired at different points in time.
The research appeared in the July 30 issue of the online journal PLoS One.
So: They evolved separately, at different points of time. But what good is it to have a decoder if you've got no way to transfer the amino acids to the protein chain?
And if it doesn't convey an advantage, why would it evolve?
Yes, yes, I know. The answer's out there, we just don't know it yet. But hasn't anyone noticed that the more we understand, the harder the questions get?
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Jul '11
Re: For Peter: Protein Synthesis
I had the pleasure of dining with Sir Francis Crick, ala DNA discovery fame, when I was in college taking up biochemistry 25 years ago. At the time he was believing that life on earth was seeded from outer space since the more he learned the more befuddled he became.
The answer is that the decoder did confer an advantage and the real question is what that advantage was. Was the decoder there in vestigial fashion comes to mind as a good question, only later be used for an alternate purpose?
Edited on Dec 5, 2011 at 12:35pmJun '10
Re: For Peter: Protein Synthesis
What is most ridiculous is the disparity between the little evidence they have and the level of certainty that most Neo-Darwinists exhibit.
It is ridiculous for scientists, who know so much about the minutiae of these processes and have really pushed the boundaries so far in this realm, to cling to such a doctrine in a religious way. With polemics, tirades and tantrums, too. Very unbecoming for "men of science".
Unscientific scientists are everywhere these days.
Jun '10
Re: For Peter: Protein Synthesis
DocJay: I had the pleasure of dining with Sir Francis Crick, ala DNA discovery fame, when I was in college taking up biochemistry 25 years ago. At the time he was believing that life on earth was seeded from outer space since the more he learned the more befuddled he became.
The answer is that the decoder did confer an advantage and the real question is what that advantage was. Was the decoder was there in vestigial fashion comes to mind, later being used for an alternate purpose? · Dec 5 at 11:49am
Doc, fix your last sentence there -- so your erudition will shine through. I can't get it.
Mar '11
Re: For Peter: Protein Synthesis
Cool! I guess that video explains why I hear music in my head all the time, too. Is the music the same for everyone or does it differ according to one's individual RNA/DNA?
Jun '10
Re: For Peter: Protein Synthesis
It depends on where you plunk the needle down, Gus. Sheesh.
Mar '11
Re: For Peter: Protein Synthesis
Larry Koler
It depends on where you plunk the needle down, Gus. Sheesh. · Dec 5 at 12:14pm
Good...um...point.
Re: For Peter: Protein Synthesis
Oh, Claire, this is way above my pay grade--even trying to appreciate it (forget about understanding it) gives me a headache. Calling Dr. David Berlinski.
Mar '11
Re: For Peter: Protein Synthesis
This is exactly what makes being a scientist so much fun.
Apr '11
Re: For Peter: Protein Synthesis
Larry Koler: What is most ridiculous is the disparity between the little evidence they have and the level of certainty that most Neo-Darwinists exhibit.
Unscientific scientists are everywhere these days. · Dec 5 at 11:50am
I agree. There's a huge difference between science and scientism.
Jul '10
Re: For Peter: Protein Synthesis
Oh, I would argue that the results from Dr. Caetano-Anolles would need to be verified by other laboratories.
Plus, it's biology and bound to be disproven a few minutes from now.
Aug '10
Re: For Peter: Protein Synthesis
Larry Koler:
...to cling to such a doctrine in a religious way. With polemics, tirades and tantrums, too. Very unbecoming for "men of science".
Is this sort of behavior among men of science all that new, though?
Acrimonious disputes among natural philosophers are common enough throughout history, as is dabbling in metaphysics.
Perhaps one of the great wonders of science is how much of it has been accomplished despite the "unscientific" temperament of many scientists.
Larry Koler:
Unscientific scientists are everywhere these days.
Could it be that it's not so much that individual scientists these days are that much less scientific than scientists used to be, but that the centralization of science has caused unscientific trends among scientists to dominate more than they did when funding and so forth was more decentralized?
All human endeavors are subject to fashion trends, and fashionable ideas are always more likely to attract funds than unfashionable ones. But when funding is available pretty much only for what's fashionable...
May '11
Re: For Peter: Protein Synthesis
If there is a creative force from outside of our system, then science is faced with an absolute "knowledge wall" it cannot penetrate since one cannot know with certainty what lies outside of a system from within that system.
Many "scientists" try to avoid this issue by proposing forces that seemingly lie within the system (thus making them theoretically utimately knowable) but which in reality are just proxies for forces from outside the system. For over 60 years "aliens did it" has been one of the most popular refuges of those who are determined to deny a creator from outside the sytem.
Claire says "the questions get harder". I say that's where humanity is separated from the herd. How do you handle knowing there are things you cannot know with certainty?
Jun '10
Re: For Peter: Protein Synthesis
Midget Faded Rattlesnake
Larry Koler:
...to cling to such a doctrine in a religious way. With polemics, tirades and tantrums, too. Very unbecoming for "men of science".
Is this sort of behavior among men of science all that new, though?
Acrimonious disputes among natural philosophers are common enough throughout history, as is dabbling in metaphysics.
Perhaps one of the great wonders of science is how much of it has been accomplished despite the "unscientific" temperament of many scientists.
Larry Koler:
Unscientific scientists are everywhere these days.
Could it be that it's not so much that individual scientists these days are that much less scientific than scientists used to be, but that the centralization of science has caused unscientific trends among scientists to dominate more than they did when funding and so forth was more decentralized?
All human endeavors are subject to fashion trends, and fashionable ideas are always more likely to attract funds than unfashionable ones. But when funding is available pretty much only for what's fashionable... · Dec 5 at 12:26pm
And this is why I follow you, MFR. Spot on.
Mar '11
Re: For Peter: Protein Synthesis
Larry Koler: What is most ridiculous is the disparity between the little evidence they have and the level of certainty that most Neo-Darwinists exhibit.
It is ridiculous for scientists, who know so much about the minutiae of these processes and have really pushed the boundaries so far in this realm, to cling to such a doctrine in a religious way. With polemics, tirades and tantrums, too. Very unbecoming for "men of science".
Unscientific scientists are everywhere these days. · Dec 5 at 11:50am
It's all about presuppositions. If you reject a priori any explanation not empirically observable then you are left with what you are left with.
Jul '11
Re: For Peter: Protein Synthesis
Larry, I happen to believe in God and as a matter of fact the really Christian version thereof. Science neither confers nor disproves the issues of God but I see miracles everywhere I look and there is more amazement and diversity in a gram of rich soil under a microscope than there is in an acre to be seen with a naked eye.
I attempted to fix my final sentence. I also name dropped not to prove that scientists were idiots or fashionable or even brilliant but to show how some deal with the wall when they hit it.
MFR, trends in medicine, science and elsewhere become far more humorous as we travel through the decades. They will always be there and currently the driving force is financial.
Jun '10
Re: For Peter: Protein Synthesis
Little evidence? Really? I thought this discussion posting was about science. Don't get me started...
Jun '10
Re: For Peter: Protein Synthesis
kgrant67
Larry Koler: What is most ridiculous is the disparity between the little evidence they have and the level of certainty that most Neo-Darwinists exhibit.
It is ridiculous for scientists, who know so much about the minutiae of these processes and have really pushed the boundaries so far in this realm, to cling to such a doctrine in a religious way. With polemics, tirades and tantrums, too. Very unbecoming for "men of science".
Unscientific scientists are everywhere these days. · Dec 5 at 11:50am
It's all about presuppositions. If you reject a priori any explanation not empirically observable then you are left with what you are left with. · Dec 5 at 12:38pm
But, if you aren't left with much, then your level of certainty must be in sync with that. We have been letting these cretins talk down to us for 160 years now and all they can do is solve one theory's problem with another new theory about why that just might be.
Where are the intermediate forms? They say that these forms only exist for a short time -- well, that's not data that's just an explanation (another theory).
Oct '10
Re: For Peter: Protein Synthesis
It is encouraging that people are finally focussing on the central conundrum—the origin of the first replicator. Once you have that replicator, the neo-Darwinian synthesis seems adequate to explain all of the complexity expressed thenceforth, but until you have that replicator, the whole mechanism of variation and selection which is evolution isn't operational.
Let's say the simplest free living organism has an information content of around one megabit. Well, a simple calculation shows that if every elementary particle in the universe were a chemical laboratory performing random protein assembly every Planck time, the universe would have produced about 500 bits of structured functional information to date.
It is this huge gap which caused Francis Crick to invoke directed panspermia, which, in my view, simply pushes the problem elsewhere.
Folks, one can't do justice to the origin of life in 200 words. Here is a long form take on the puzzle in my review of Stephen Meyer's Signature in the Cell.
Jun '10
Re: For Peter: Protein Synthesis
DocJay: Larry, I happen to believe in God and as a matter of fact the really Christian version thereof. Science neither confers nor disproves the issues of God but I see miracles everywhere I look and there is more amazement and diversity in a gram of rich soil under a microscope than there is in an acre to be seen with a naked eye.
...
We are in complete agreement here. The only thing I have to say is that I, too, used to believe in Darwinism until I read Michael Behe's The Edge of Evolution, Ann Coulter's Godless and Phil Johnson's Darwin on Trial. These will make people realize that the Darwinists are not scientists but polemicists first. It's really a logical issue that is in contention here.
DocJay: ...
I attempted to fix my final sentence. I also name dropped not to prove that scientists were idiots or fashionable or even brilliant but to show how some deal with the wall when they hit it.
...
Much clearer now -- Thanks. (I never mind other people getting to meet famous people -- I mean I'm a little jealous and it makes me feel low but well anyway....)
Jun '10
Re: For Peter: Protein Synthesis
John Walker: ...
Once you have that replicator, the neo-Darwinian synthesis seems adequate to explain all of the complexity expressed thenceforth, but until you have that replicator, the whole mechanism of variation and selection which is evolution isn't operational.
Let's say the simplest free living organism has an information content of around one megabit. Well, a simple calculation shows that if every elementary particle in the universe were a chemical laboratory performing random protein assembly every Planck time, the universe would have produced about 500 bits of structured functional information to date.
It is this huge gap which caused Francis Crick to invoke directed panspermia, which, in my view, simply pushes the problem elsewhere.
...
500 bits??? Is that all?
Simply stop all the other biochemical sophistry and explain the Cambrian Explosion. then.
Just that alone sinks all this silly talk about "Once you have that replicator, the neo-Darwinian synthesis seems adequate to explain all of the complexity expressed thenceforth..."