Posted on 06/15/2017 12:50:19 PM PDT by Kaslin
Genes are a symbolic medium - and the semantic closure is the correlation that constrains and conveys what the genes represent. For example, codons only represent amino acids if you have the system in place to interpret the functional relationship of the medium (aaRS).
Consider the data input for a CAD model that is then created (physically expressed) with a 3D printer or rapid prototype machine. Now appreciate the information transfer from an idea, to the symbolic medium of software, to the specific design – the translations that must occur – and the system(s) that must already be in place to interpret the functional relationships with the proper correlation and constraints.
“I mean maybe primordial RNA1 has an extra atom or few compared to primordial RNA2. And the structural difference makes the two incapable of catalyzing each other.”
I’m not sure what “primordial” RNA would look like.
But keep in mind, many modified RNA are reactive with non-modified RNA.
Your scenario could in fact actually be speculated to increase the odds of reaction and replication rather than hinder it.
>>That was discovered about 20 years ago.
Sounds simple.
Have simple, self-replicating RNA polymers been synthesized in the lab since then?
“the semantic closure is the correlation that constrains and conveys what the genes represent.”
Thanks. I am not sure I exactly get it, but this was direct and helps.
My comment is that DNA is a lot more than just genes and codons.
” For example, codons only represent amino acids if you have the system in place to interpret the functional relationship of the medium (aaRS)”
Yes. And codons in one direction may not be codons in another direction, but may have a separate non-coding function.
Quite multi-layered in its structural function wherein the information is inherent in the chemical properties and associated structures.
Yes.
Here us a great talk about the discovery of catalytic RNA by Tom Cech.
It’s 10 minutes. You can jump to 9:45 if you want to see the last part where the RNA catalytic properties were discovered.
Note that this is RNA alone adding a base to itself.
With increased diversity of molecular species manufactured in the process.
>>Note that this is RNA alone adding a base to itself.
Where did the RNA that added the base to itself come from?
Suppose I make a machine that makes copies of itself, but sometimes makes the copies imperfectly. While most of the imperfect copies would probably be machines that were less efficient at making copies, or machines that made the copies poorly which would end in branches of generations that ended in failure....still at least some changes might make the machine actually better at making copies. But then that beneficial change is lost in the next generation which it made correctly--that is without the beneficial change.
iMissThatDidYa?
Throughout the presentation Dr. Cech references "purified RNA". Collected from....?
Then he describes splicing a molecule into an artificial transcript:
https://www.youtube.com/watch?v=WAChisSiW3o&feature=youtu.be&t=9m
The primary revelation that proteins are not requisite for RNA splicing is cool - however Splicing a molecule into an an artificial RNA polymer is a HUGE shortfall from manufacturing self-replicating RNA from atomic precursors.
So, at least per the video evidence you provided, the answer is NO - self-replicating RNA polymers have NOT been synthesized in the lab since then.
“Where did the RNA that added the base to itself come from?”
It was the same sequence as tetrahymena ribosomal RNA which was synthesized to make sure there were no proteins present, which could have been catalyzing the reaction and Cech wanted to know if it was solely RNA carrying out the reaction.
“With increased diversity of molecular species manufactured in the process.”
Yes, could be.
Except the next generation isn't made "correctly" - it's made "directly", as a molecular copy of the genome containing the beneficial change.
In the reaction a base is added - the RNA is not simply cut.
You also are unaware that this initial finding was followed up and it was found that multiple RNA bases could be added to a string of RNA.
This is self replication.
Except in that video Dr. Cech doesn’t mention synthesized RNA until he describes splicing a molecule into an artificial transcript:
https://www.youtube.com/watch?v=WAChisSiW3o&feature=youtu.be&t=9m
Is there a published source that describes the methodology by which the “purified RNA”, referenced throughout the presentation prior to 9m0s, was obtained?
Then it wont benefit from natural selection.
Yes. Adding a base - that would be the SPLICING part.
splice (splīs)
►
>>This is self replication.
And 2+2=5
As interesting and exciting as "multiple RNA bases could be added to a string of RNA" is - it's still not the sort of complete (and sustained) self-replication required to demonstrate evolutonary abiogenesis in the lab, let alone in Nature.
>>Then it wont benefit from natural selection.
Yes, the benefit is manifested when the beneficial mutation is copied EXACTLY to the next generation.
You don’t understand the chemistry.
It is a splicing out reaction but you do not understand that the spliced out stretch has an additional base added.
That is self replication.
PubMed. Cech
“Yes. Adding a base - that would be the SPLICING part.”
No.
Splicing does not need to add anything. Splicing film does not add a frame.
As far as DNA your examples here are like restriction endonuclease mediated DNA splicing. An extra base is not added.
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