And it carries that information, like DNA, because it can serve as a template for it’s own replication, while also being able to act as a catalyst. DNA doesn’t self-translate any more than RNA does.
There is no contemporary hypothesis for the origin of life that posits life began with a self-translating RNA molecule.
appsandorgs: The cell’s set of aaRS proteins establish the genetic code by binding tRNA and their cognate amino acid cargo together, prior to synthesis in the ribosome
Harshman: Not exactly true.
Nature: (Harshman’s posted reference) Aminoacyl-tRNA synthetases (aaRSs) implement the correct assignment of amino acids to their codons and are thus inherently connected to the emergence of genetic coding. These enzymes link tRNA molecules with their amino acid cargo and are consequently vital for protein biosynthesis.
Harshman: Not exactly true.
American Society of Microbiology: Aminoacyl-tRNA synthetases (aaRSs) are modular enzymes globally conserved in the three kingdoms of life. All catalyze the same two-step reaction, i.e., the attachment of a proteinogenic amino acid on their cognate tRNAs, thereby mediating the correct expression of the genetic code.
[Mod insert: source (pdf) ]
Harshman: Not exactly true.
Journal of The RNA Society: The aminoacyl-tRNA synthetases are an essential and universally distributed family of enzymes that plays a critical role in protein synthesis, pairing tRNAs with their cognate amino acids for decoding mRNAs according to the genetic code.”
[Mod insert: source abstract ]
Harshman: Not exactly true.
FEMS Microbiology Review: The accurate synthesis of proteins, dictated by the corresponding nucleotide sequence encoded in mRNA, is essential for cell growth and survival. Central to this process are the aminoacyl-tRNA synthetases (aaRSs) … The aaRSs are essential for coupling the correct amino acid and tRNA molecules.
[Mod insert: source abstract ]
Harshman: Not exactly true.
FASEB: Aminoacyl-tRNA synthetases (AaRSs) are valuable “housekeeping” enzymes that ensure the accurate transmission of genetic information in living cells, where they aminoacylate tRNA molecules with their cognate amino acid and provide substrates for protein biosynthesis.
[Mod insert: likely source]
Harshman: Not exactly true.
Heridity/The Genetics Society: tRNA molecules cannot self aminoacylate; instead, there are 20 amino acid-specific aminoacyl-tRNA synthetases (aaRSs) that perform this function. Thus, it is these aaRSs that actually define the familiar matrix of the genetic code, by linking the specific amino acids and tRNAs with the corresponding anticodons.
Harshman: Not exactly true. You can change the code by changing…
What?? You can do what??
You mean you could change a select portion of the tRNA that doesn’t cause the aaRS to reject the tRNA and perhaps cause a change to occur in the outcome?
Is that your reasoning?
“aminoacyl-tRNA synthetases implement the code by binding tRNAs to their cognate amino acids prior to synthesis” is “not exactly true” because you could game the system to change the code?
That’s your reasoning, isn’t it? That’s exactly your reasoning.
Take snapshot Paul King.
Harshman: Why do you ignore the tRNAs?
I don’t ignore the tRNAs. I have many times thought of adding them to the equation, but I keep my comments in-line with the published literature and the history of discovery. I can easily add the tRNA to the mix, which only increases the number of DNA sequences that must be coordinated with one another to achieve function – i.e. for a codon to exist as part of a rate-independent control system perpetuated over time. Congratulations, you’ve compounded the issue (should you ever acknowledge the physics involved).
Rumraket, you’ve spent this entire thread trying your level best to misunderstand the topic under discussion. I’ve explained the distinction between rate-dependent dynamics and rate-independent control to the point that the lint on the floor has now figured it out. The Pattee paper explained it as well (much better than I). Yet, you’ve painted yourself safely into a corner, and nothing else can be expected from you now.
I am confident that if Mrs Johnson occasionally ponders the origin of life, and then reads in the paper about a new technology called CRISPR, allowing scientists to literally change the informational content of a gene by editing the codons that make up that gene, you’ll be there to assure her that a self-replicating RNA contains information just like DNA.
No codons (or physics) required.
By the way, if anyone is wondering what I said to cause all this fuss, here it is:
cheers…
[Mod edits to insert sources]
I’m trying to get you to understand something other than your current tunnel-vision belief. How can it be so hard? The mapping between amino acids and mRNA codons depends on four things: The region of the aaRS that binds to the particular amino acid, the region of the aaRS that binds to a particular tRNA, the region of the tRNA that binds to the aaRS, and the anticodon loop. The right mutation to any one of those would change the genetic code. Offhand, I don’t know which of these is most common, but you should look at the literature on variant codes, which might tell you.
But let me ask this important question again, since you have consistently ignored it: what is your point?
No, you’ve spent this entire thread trying your best to ignore my requests for clarification. To get at the broader point.
You haven’t explained this even once. You have referred to these terms but never bothered to explain either what they mean, nor what point you wish to make by referring to them.
What corner is that? The one where I have repeatedly asked for clarification, and I have actually done the part of explanation that make sense of the statements you keep referring to, such as the capacity for DNA to “carry information”?
Yes I will be happy to repeat the patently obvious fact that the sense in which DNA can carry information which can also be performed by RNA, is to serve as a template for it’s own replication. That it the only sense that CAN be made of that statement since DNA does not, in fact, self-translate.
So it’s just idiotic to keep insisting, as you appear to be doing, that a self-replicating RNA at the origin of life can’t also function as an entire translation system, because nobody working in the field thinks or proposes that it can, and DNA can’t do that either.
So there just is no other way to make sense of the statement that RNA can serve as both a catalyst and carry information, than to say it can carry sequence information through it’s property of being able to serve as a template through Watson-Crick basepairing, just like DNA.
In fact, I am so convinced of the truth of this I asked it of chatGPT. Notice what it says in the clarification:
Me: Explain to me how you interpret this sentence “At the origin of life, RNA can carry information just like DNA and be a catalyst at the same time.” In what sense do you think the capacity to carry information by RNA is meant, that would be like how DNA does it?
ChatGPT
The sentence “At the origin of life, RNA can carry information just like DNA and be a catalyst at the same time” highlights two critical roles of RNA in early life forms:
- Information Carrier: RNA can store and transmit genetic information in a manner similar to DNA.
- Catalytic Function: RNA can also act as a catalyst, speeding up biochemical reactions.
Here’s how RNA’s capacity to carry information is akin to that of DNA:
Information Carrying by RNA:
1. Genetic Code: RNA, like DNA, is composed of nucleotides. Each nucleotide contains a sugar, a phosphate group, and a nitrogenous base. In RNA, the sugar is ribose, and the nitrogenous bases are adenine (A), cytosine (C), guanine (G), and uracil (U) (replacing thymine (T) in DNA). These nucleotides are arranged in a specific sequence that encodes genetic information, just as the sequence of nucleotides in DNA does.
2. Template for Protein Synthesis: RNA can serve as a template for protein synthesis. In modern cells, messenger RNA (mRNA) transcribes the genetic code from DNA and carries it to ribosomes, where it is translated into proteins. This process demonstrates RNA’s ability to carry genetic information and direct the synthesis of proteins, a crucial aspect of cellular function.
3. Self-Replication: In the context of the origin of life, RNA is hypothesized to have the ability to self-replicate. Certain RNA molecules, known as ribozymes, can catalyze their own replication or the synthesis of complementary RNA strands. This means RNA could have carried genetic information and propagated itself without the need for DNA or proteins, supporting the idea of an “RNA world” where RNA was the primary molecule for both genetic information storage and catalysis.
Comparison to DNA:
1. Stability: DNA is more stable than RNA due to its double-stranded structure and the absence of the reactive 2’-hydroxyl group on the ribose sugar. This stability makes DNA better suited for long-term storage of genetic information. However, RNA’s relative instability and single-stranded nature might have been advantageous in early life forms, allowing for more dynamic and versatile functions.
2. Redundancy and Error Checking: DNA uses complementary base pairing to form a double helix, which provides a mechanism for error checking and repair. RNA, being single-stranded, lacks this redundancy, but its ability to fold into complex structures allows it to perform multiple functions, including catalysis.
Catalytic Role:
In addition to carrying information, RNA’s ability to fold into complex three-dimensional structures enables it to function as a catalyst. Ribozymes, or RNA enzymes, can catalyze a variety of biochemical reactions, including peptide bond formation in protein synthesis (as part of the ribosome) and RNA splicing. This dual capability of RNA (information storage and catalysis) supports the hypothesis that RNA could have played a central role in the early development of life, before the evolution of DNA and protein-based enzymes.
Summary:
In summary, the sentence emphasizes that RNA, at the origin of life, had the remarkable ability to store and transmit genetic information similarly to DNA while also acting as a catalyst for biochemical reactions. This dual functionality supports the concept of the RNA world hypothesis, where RNA was a fundamental molecule in early life forms, bridging the gap between simple organic molecules and the complex systems seen in modern biology.
Me: Speaking exclusively of the origin of life, which of the above senses of the capacity to carry information by RNA, do you think is most important?
ChatGPT
When speaking exclusively of the origin of life, the most important sense of RNA’s capacity to carry information is its role as a template for self-replication. This capacity is crucial because:
Self-Replication
1. Genetic Continuity: Self-replication allows RNA to ensure the continuity of genetic information across generations. This is fundamental for the persistence and evolution of early life forms. Without self-replication, any genetic information encoded in RNA would be lost, making the emergence of life unsustainable.
2. Mutation and Evolution: Through self-replication, RNA molecules can undergo mutations, leading to variations. These variations provide a basis for natural selection, driving the evolutionary processes that can lead to increased complexity and the development of more efficient biological systems.
3. Pre-DNA Role: Before the evolution of DNA, RNA’s ability to self-replicate would have been essential for the propagation of life. The self-replicating nature of RNA means it could have carried the genetic information necessary for the development of early life forms, performing the functions that DNA later took over.
Supporting Points
While RNA’s role as a messenger in protein synthesis (like modern mRNA) and its ability to fold into catalytic structures (ribozymes) are also significant, these functions presuppose the existence of a relatively advanced and organized cellular machinery. At the very origin of life, such complex systems had not yet evolved. Therefore, the fundamental requirement would have been a molecule capable of storing genetic information and replicating itself.
Summary
Thus, in the context of the origin of life, the capacity of RNA to serve as a template for self-replication is paramount. This capacity underpins the very existence and continuity of life, enabling the initial steps toward biological complexity and the eventual evolution of more sophisticated genetic and catalytic systems.
Turns out ChatGPT agrees that the idea that RNA is thought, proposed, halluscinated, interpreted, or inferred to have functioned as a self-translator and that this is the sense in which the RNA must have been able to “carry information just like DNA” is a ridiculous notion. It’s amazing that a chat-bot shows a higher degree of comprehension of the sentence you’ve been flailing about in this thread than you do.
All your blather about “rate-independent control”, “self-reference”, “closure”, “states of coordination”, “molecular constraints”, and all the rest of your favorite terms are just useless blather. You are attacking a position nobody holds and a network of logic gates connected to the internet could have explained this to you.
Checking back in …
I don’t know if either of you have ever had the opportunity to familiarize yourself with knowledge about strategy, opposing force, positioning and the like (Sun Tzu and all that). It’s a fascinating and mature subject matter, with an enormous body of thought and writing. I can tell you that taking the position of continually ‘not knowing’ what the point is, or, exhibiting some form of persistent confusion about what’s being said in your area of expertise — those things are inherently a flank. Flanking is a strategy to avoid the strength of an opposing position by changing the focus away from where it is, moving it to more desirable territory. It’s a great strategy for a mid-pack player trying to move to the front, but it’s not a heads-up strategy and it’s certainly not the commanding defense from a leader.
To be successful, flanking requires your opponent to “take the bait” (to participate in the change of focus) and it isn’t played without costs. The longer the conflict goes on — more and more gets put on the table — and at some point, carrying on a strategy of “what-huh?” becomes untenable. It can lead to absurdities.
It leads to absurdities like the specter of Harshman appearing to disagree with the published analysis of scientist after scientist after scientist in journal after journal. He needs to disagree with them because they are all saying the exact same thing that I am saying — and obviously I must be interrogated and opposed. Instead of acting from a position of strength (and simply acknowledging the facts in the literature) he attempts to shift the focus to his list of “four sites” so he can beat me over the head with it — as if his list somehow super-cedes or nullifies any of the published references saying the same thing I am. Does anyone actually believe that Harshman disagrees with the literature? Of course not. The cell’s set of aaRSs implement the genetic code by binding tRNA to their cognate amino acids. Like I said, the facts are not even controversial.
And then true to form, Harshman completes his comments by asking ‘what’s the point?’ It’s a purposely dismissive question, which he asks in order to avoid the point as it’s already been presented. It’s a weak position being paraded as strength. If Mr. Harshman had a way to show that my position was flawed in some fundamental way, he would have laid it out from the start. But he can’t, so he didn’t.
The same is true of Rumraket, in fact it’s worse. I obviously could be wrong about this, but Harshman strikes me as a person that an authoritative figure like Brenner (or Pattee) might have sat down with (perhaps with a beverage in hand) and had a meaningful dialogue about the necessary (predicted and confirmed) semiotic nature of the gene system. Rumraket however is just not that person.
Among Rumraket’s attempts to avoid what I said at the top of this thread, he has invented the preposterous idea that I must somehow be arguing that DNA replicates itself. This is a particularly useful distortion of the issue, which he can attack over and over again — with his arms in the air, utterly dismayed by how wrong-headed I am, imagining himself to be busy at the work of responding forcefully to my claim. To his way of thinking, to say that “DNA conveys information by virtue of codons” is to effectively say nothing at all, because the codon is immediately dismissed as if it has no role to play in the claim.
And it is not in the least bit difficult to see Rumraket’s avoidance of that role. Simply do a search for the word “codon” among Rumraket’s comments on this thread and count up the number of times he (himself) uses the word. You will find that among the 5,300 words he’s typed on this thread, he uses the word “codon” a grand total of six times. Five of those six instances are unrelated to directly addressing my claim. Only one is used to make any form of rebuttal at all.
This is that rebuttal:
appsandorgs: DNA conveys information by virtue of codons.
Rumraket: Then mRNA conveys information by virtue of codons too. DNA doesn’t translate itself any more than RNA does.
For Rumraket a codon is just three bases in a row … and he immediately goes back to the distortion he wants to sell – the more desirable territory.
I have suggested that it is misleading for scientists and science popularizers to speak to the lay public about a putative self-replicating RNA at the origin of life and say, “RNA can carry information just like DNA and be a catalyst at the same time”. The overarching point is that for RNA to convey information like DNA (by virtue of codons, tokens of genetic memory), RNA would have to solve the origin of symbolic control, which is basically the OoL problem on the head of a pin. It’s a tad bit much to leave out of the conversation.
Rumraket says that my comment “immediately and naturally translates to a person [me] doubting the possibility that RNA can contain a coding region”. But to “contain a coding region” would, of course, first require a semiotic system to establish a set of codons and a code. But he then turns right around (in palpable exasperation) to assure me that at the OoL no one “claims, thinks, believes, suggests, or infers that such a thing ever occurred. Ever.”
Thus, making my point, comment after comment, as his vitriol increases with each passing round.
More like exasperation, I think.
“A semiotic system” is your model. You appear to think your model has more merit than reality.
I have no role in the establishment of biosemiosis as a discipline in science. I was a child when the connection was made between Peirce’s triadic relation, Turing’s programmable symbol system, Von Neumann’s autonomous self-replicator, and Crick’s biological code.
Thank you, Alan. You’ve always had the knack of capturing the moment in a short comment, and you never hide your motivation.
When the science is against you, and the math is against you, and the history of discovery is against you … ignore those things and make it about a person instead. It soothes the soul troubled by logic and observation.
It’s the same for you too, because … you guessed it, DNA doesn’t translate itself. That just is what a codon is.
So DNA doesn’t “convey information” in any way that is different from RNA.
So if DNA conveys information by virtue of codons, so does RNA. Heck, if anything RNA conveys information by virtue of codons more directly than does DNA since it is the RNA that is translated, not the DNA. The anticodon on tRNA (not DNA) comes into contact with and basepairs with mRNA (not DNA). The aaRS enzyme has tRNA (not DNA) as one of it’s substrates.
If the “conveys information” part of DNA has to do with the genetic code and translation at all it is only indirectly as the transgenerational storage-medium that allows the sequence containing the codons to be passed on from generation to generation. The actual translational process is all from the RNA codons, not from DNA.
So the only way the sentence “RNA conveys information like DNA” could have rationally been meant in the origin of life context, would be as a template for transgenerational sequence-information transfer. Not as a reference for it’s putative capacity to function simultaneously as a self-replicating ribozyme while also an entire translation system (a proposal still nobody has advanced. There is no paper anywhere that advances this hypothesis, and you have ignored my earlier request to produce one despite implicitly claiming there was. You have ignored it because you actually know you are obviously wrong.
But do go on returning to this thread replying only with attempts to sort of characterize the entire discussion in a way where you’re right about something nobody has disputed.
Man, turn down the light! The projection is too powerful!
No Rumraket … it’s not the same for me at all. I know the difference between a rate-dependent template and a rate-independent medium of information. I’ve seen the Periodic Table — and the remainder of your post is just more of you dancing around on your hobby horse. It’s entirely irrelevant to the topic of conversation.
I don’t need you to correct me on what you think I meant to say. You, however, have done little else since the very start of this thread.
Starting here (in your second post):
No, that is not at all what I “meant to say”. I said exactly what I meant to say.
I also said this: (my first post on this thread)
I said this as well:
And finally, I said this:
I said and meant every word of those statements (because they are true).
Good grief, in a conversation about the lay public being potentially misled into thinking that a self-replicating ribozyme at the OoL can convey genetic information like DNA, you’ve managed to stitch yourself into a cocoon where ‘a codon is just three bases in a row’. You can’t even make this stuff up — and you appear to be completely willing to personally make my point for me (over and over again) rather than give up on your incessant attempts to make my comments about something else. I’m not entirely sure you can stop yourself at this point.
It only appears that way to you because your all-rhetoric approach is so shallow. Notice how you never cite any primary OoL literature? Notice how you’ve never answered my question about metabolism-first hypotheses? That’s because you started with IDcreationist misrepresentations of OoL research.
If they are saying the exact same thing that you are saying, you would have quoted them doing so. To my knowledge, nothing from the secondary or tertiary literature has ever said anything even close to that. This is the problem with pretending to be scientific while limiting yourself to rhetoric.
You’re clearly unable to distinguish facts from the metaphors used to describe them. This is another problem with pretending to be scientific while limiting yourself to rhetoric.
“Good grief” is right. To my knowledge, no one with any familiarity with OoL research has ever described the OoL as a singular, discrete event. The only people misleading the lay public are the IDcreationists using straw men like that whopper.
So, why is it all hearsay? Who, exactly, do you think is misleading/has misled the lay public about this? When? How?
I did.
appsandorgs: The cell’s set of aaRS proteins establish the genetic code by binding tRNA and their cognate amino acid cargo together, prior to synthesis in the ribosome
Nature: Aminoacyl-tRNA synthetases (aaRSs) implement the correct assignment of amino acids to their codons and are thus inherently connected to the emergence of genetic coding. These enzymes link tRNA molecules with their amino acid cargo and are consequently vital for protein biosynthesis.
American Society of Microbiology: Aminoacyl-tRNA synthetases (aaRSs) are modular enzymes globally conserved in the three kingdoms of life. All catalyze the same two-step reaction, i.e., the attachment of a proteinogenic amino acid on their cognate tRNAs, thereby mediating the correct expression of the genetic code.
Journal of The RNA Society: The aminoacyl-tRNA synthetases are an essential and universally distributed family of enzymes that plays a critical role in protein synthesis, pairing tRNAs with their cognate amino acids for decoding mRNAs according to the genetic code.”
FEMS Microbiology Review: The accurate synthesis of proteins, dictated by the corresponding nucleotide sequence encoded in mRNA, is essential for cell growth and survival. Central to this process are the aminoacyl-tRNA synthetases (aaRSs) … The aaRSs are essential for coupling the correct amino acid and tRNA molecules.
FASEB: Aminoacyl-tRNA synthetases (AaRSs) are valuable “housekeeping” enzymes that ensure the accurate transmission of genetic information in living cells, where they aminoacylate tRNA molecules with their cognate amino acid and provide substrates for protein biosynthesis.
Heridity/The Genetics Society: tRNA molecules cannot self aminoacylate; instead, there are 20 amino acid-specific aminoacyl-tRNA synthetases (aaRSs) that perform this function. Thus, it is these aaRSs that actually define the familiar matrix of the genetic code, by linking the specific amino acids and tRNAs with the corresponding anticodons.
Allow me to add another: (Cue the invective).
The RNA Tie Club (circa 1955): Each amino acid would combine chemically, at a special enzyme, with a small molecule which, having a specific hydrogen-bonding surface, would combine specifically with the nucleic acid template. This combination would also supply the energy necessary for polymerisation. In its simplest form there would be 20 different kinds of adaptor molecules, one for each amino acid, and 20 different enzymes to join the amino acid to their adaptors, Sydney Brenner, with whom I have discussed this idea, calls this the “adapter hypothesis".
Hopefully I can clear this up.
You find the statement “RNA conveys information like DNA” problematic because of the following reason. DNA conveys information via codons, but in order to translate the information of a codon, it requires more than just three nucleotides in a row. RNA can have three nucleotides in a row, but that - by itself - doesn’t cut it.
The problem here is that… if that’s your standard for something “to convey information”, then DNA also doesn’t convey information either. DNA with three nucleotides in a row by itself isn’t enough to translate a codon into a specific amino acid. Not even a whole genome of DNA can do this by itself. Then again, you may repeat yourself by pointing out that DNA also holds the “twenty sequences of genetic memory” for the aaRS that are required to charge tRNAs with their cognate amino acids (establishing the genetic code). Although, there is the tantalizing possibility that RNA originally also held this memory prior to DNA [see here, here and here]. But even setting that aside, all this “genetic memory” is useless without all the other stuff that DNA requires to convey it.
Obviously, we both know that when we say “DNA conveys information”, we don’t mean to say that DNA does X, Y and Z all by itself completely naked to the environment. It’s part of a bigger system that allows it to function. So, in what sense does DNA actually convey information while still being part of a larger system? How does it exactly do this? If there is anything the phrase “conveys information” references, it is simply the fact that DNA functions as a template to direct the sequence of a new strand during it’s synthesis. [additionally, you may also want to say that sequence motifs in DNA can be binding sites for proteins]. DNA functions as a template to direct RNA polymerization or to direct DNA polymerization. The sequence of the template strand is ‘transferred’ or ‘preserved’ in the new RNA or DNA strands. That’s what the “information” refers to. And yes, RNA can also act as a template; and RNA-template directed synthesis of RNA or DNA still occurs in contemporary biology: see viruses and retrotransposons.
So, if you agree with the statement “RNA can act as a template for nucleotide polymerization such that the the nucleotide sequences of the template strands are transferred/preserved in the newly synthesized strands, just like DNA” and if you are okay with the phrase “RNA conveys information like DNA” as a shorthand for that fact, then we can all finally move on in peace.
You didn’t. None of them mention the OoL.
I think you might be operating under the false idea that there is actually a misunderstanding going on here.
I have said that DNA doesn’t convey information like the self-replicating ribozyme often discussed at the origin of life. DNA conveys information via codons (which enables open-ended control of protein synthesis) while RNA conveys information as a fully dynamic template for pairing complimentary bases.
To this, Rumraket responds “Sure, let’s make that comparison, but first we have to remove everything from our analysis that causes the codon to exist … Oh look, now they’re the same thing!”
It’s ridiculous. It’s a non-starter. What was that line from Einstein … you can’t understand a Beethoven symphony “by a graph of air pressures”. But that is exactly what Rumraket insists upon here. He wants to study a book of history by isolating the way in which ink is absorbed into sheets of bleached wood pulp (for crying out loud). I had this same conversation with Mercer. Using his standard of analysis, he could not even know that the computer he types on uses a symbolic code to function. Does anyone really believe that a physicist could not analyze the workings of a computer and not know (and describe in the language of physics) that it uses symbolic tokens (instantiated in voltage) to achieve its function? Mercer and Rumraket would be over that physicist’s shoulder telling him, “Hey” you can measure how electrical voltage interacts with the logic gates and whatnot, but you can’t start comparing inputs to outputs and that sort of thing — “hands off the rate-independent aspects of the system!”
Actually, come to think of it, this is something that Von Neumann (and Pattee) wrote about decades ago. Such systems fundamentally require two complimentary (and accurate) descriptions of their function in order to be fully understood — one for the dynamic (rate-dependent) aspects of the system and another for the semiotic (rate-independent) aspects of the system. And of course, in biology, the most obvious of these latter descriptions is the Genetic Code itself — a scientific record of the observed relationships between codons and amino acids (cue the invective). When Nirenberg told Matthaei ”Let’s hit it with poly-u”, Mercer and Rumraket would have been there to say “Whoa, no need for that, we already know how base-pairing works!” This whole argument being put forth is just nonsense.
I made a rather mild quip about misleading statements regarding RNA and DNA, and I was asked to make my case. I did so in a couple of paragraphs without an ounce of snark or disrespect, and what I wrote in support of my statement was not only true, but uncontroversial — can be easily supported from biology textbooks around the planet, not to mention 150 years of recorded history on the subject matter. And now, 45 days and 150+ comments later, I have two Peaceful Science regulars (working scientist no less) insisting that there are physical aspects of the system that are not allowed (lol) to be included in any analysis!! And as easily demonstrated from the actual text of this thread, these known facts are disallowed for no other reason than my conversation partner’s counterarguments would fall apart in a New York minute. To be blunt, it’s anti-science and anti-intellectual. Do either Mercer or Rumraket actually approach science like this? No, of course not, they are not idiots. This is being done for no other reason than to suppress valid science/history in an attempt to win an argument. A pig in lipstick.
Frankly, some of the actions taken in this thread should be an embarrassment. But unfortunately, they are not. In fact, they are rather par for the course — which is disheartening to say the least.
Take a good look Paul King:
Mercer: If they are saying the exact same thing that you are saying, you would have quoted them doing so.
appsandorgs: I did.
appsandorgs: The cell’s set of aaRS proteins establish the genetic code by binding tRNA and their cognate amino acid cargo together, prior to synthesis in the ribosome
Nature: Aminoacyl-tRNA synthetases (aaRSs) implement the correct assignment of amino acids to their codons and are thus inherently connected to the emergence of genetic coding. These enzymes link tRNA molecules with their amino acid cargo and are consequently vital for protein biosynthesis.
American Society of Microbiology: Aminoacyl-tRNA synthetases (aaRSs) are modular enzymes globally conserved in the three kingdoms of life. All catalyze the same two-step reaction, i.e., the attachment of a proteinogenic amino acid on their cognate tRNAs, thereby mediating the correct expression of the genetic code.
Journal of The RNA Society: The aminoacyl-tRNA synthetases are an essential and universally distributed family of enzymes that plays a critical role in protein synthesis, pairing tRNAs with their cognate amino acids for decoding mRNAs according to the genetic code.”
FEMS Microbiology Review: The accurate synthesis of proteins, dictated by the corresponding nucleotide sequence encoded in mRNA, is essential for cell growth and survival. Central to this process are the aminoacyl-tRNA synthetases (aaRSs) … The aaRSs are essential for coupling the correct amino acid and tRNA molecules.
FASEB: Aminoacyl-tRNA synthetases (AaRSs) are valuable “housekeeping” enzymes that ensure the accurate transmission of genetic information in living cells, where they aminoacylate tRNA molecules with their cognate amino acid and provide substrates for protein biosynthesis.
Heridity/The Genetics Society: tRNA molecules cannot self aminoacylate; instead, there are 20 amino acid-specific aminoacyl-tRNA synthetases (aaRSs) that perform this function. Thus, it is these aaRSs that actually define the familiar matrix of the genetic code, by linking the specific amino acids and tRNAs with the corresponding anticodons.
Mercer: You didn’t. None of them mention the OoL.
(He cannot stop himself)
Are you saying DNA is not a template?
And that RNA doesn’t contain codons?
It’s simply a definition. There’s no symbolism whatsoever in translation itself. So many straw men…
Another straw man.
You haven’t quoted any of misleading statements. That’s the straw man at the center of your rhetoric.
Yet you have never quoted anyone writing that. No one with the slightest familiarity with OoL research would view the OoL as a single, discrete event.
Where is metabolism?
DNA also conveys information “as a fully dynamic template for pairing complimentary bases”. That’s how it’s being replicated into more DNA and transcribed into RNA. Furthermore, the way DNA conveys information via codons is EXACTLY by being transcribed, i.e. via acting “as a fully dynamic template for pairing complementary bases”. You say that DNA does X and RNA does Y in a manner that implies X and Y are distinctly different things, but Y is the very mechanism for doing X.
Just to make sure that there is no misunderstanding; I am NOT saying that the template function is sufficient for conveying information via codons. As I have made it clear in my previous comment, the system (translation, genetic code, etc) involves more components. Neither DNA nor RNA function to convey information by themselves, but the pivotal function both DNA and RNA provide… within the larger system… to convey information is by acting as a template for pairing complementary bases.