Central Dogma of Genetics May Not Be So Central 196
Amorymeltzer writes "RNA molecules aren't always faithful reproductions of the genetic instructions contained within DNA, a new study shows (abstract). The finding seems to violate a tenet of genetics so fundamental that scientists call it the central dogma: DNA letters encode information, and RNA is made in DNA's likeness. The RNA then serves as a template to build proteins. But a study of RNA in white blood cells from 27 different people shows that, on average, each person has nearly 4,000 genes in which the RNA copies contain misspellings not found in DNA."
Central Dogma? (Score:3, Insightful)
Who do you think they are, Soulskill, NERV?
Also, science holds no dogma. If it does, it ceases to be science.
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Also, science holds no dogma.
Is that a dogma that science holds?
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More like a dogma that the philosophy of science holds.
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It may be a dogma that scientists hold, but it is more a presupposition to science than it is science.
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Re:Central Dogma? (Score:5, Interesting)
Originally it stated something along the lines of, One DNA gene is transcribed into one RNA transcript, which is then translated into one protein.
The discovery of antibodies threw that concept out the window. Variability in intron splicing and recombination means that a small handful of genes can yield a huge variety of protein products (See VDJ recombination).
Yet another twist was added with the discovery of retroviruses which reverse the direction of transcription, turning RNA into DNA. Previously we had thought the central dogma to be unidirectional.
The more we learn about life's mechanisms, the less surprised we are when exceptions to the rules are discovered. Evolution really is the ultimate hacker; constantly expanding the usefulness of very simple resources.
Also, kudos on the evangelion reference.
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I'd mod you up but, as you can see, I commented.
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"In his autobiography, What Mad Pursuit, Crick wrote about his choice of the word dogma and some of the problems it caused him:
"I called this idea the central dogma, for two reasons, I suspect. I had already used the obvious word hypothesis in the sequence hypothesis, and in addition I wanted to suggest that this new assumption was more central and more powerful. ... As it turned out, the use of the word dogma caused almost more trouble than it was worth.... Many years later Jacques M
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There are many, many twists to this sordid puzzle, but you are correct. The concept of a 1:1:1 translation has been dead for a very long time.
Re:Central Dogma? (Score:4, Funny)
The use of the term "dogma" in "Central Dogma" was incorrect from the get-go. Frankly, Francis Crick either chose to misunderstand the word or simply didn't fully grasp its connotations.
He was just looking for a more dramatic word for "hypothesis".
"Central Hypothesis" would be the more accurate name for it. It isn't a proper theory, but it does provide a framework for understanding molecular biological functions.
It's basically this (from WP): 'once information gets into protein, it can't flow back to nucleic acid.'
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I called this idea the central dogma, for two reasons, I suspect. I had already used the obvious word hypothesis in the sequence hypothesis, and in addition I wanted to suggest that this new assumption was more central and more powerful... As it turned out, the use of the word dogma caused almost more trouble than it was worth... Many years later Jacques Monod pointed out to me that I did not appear to understand the correct use of the word dogma, which is a belief that cannot be doubted. I did apprehend th
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To throw a further spanner in the works, a large proportion of non-genetic DNA (i.e. the stuff that doesn't get eventually converted into proteins) has functional aspects — it is transcribed into RNA and then used directly for cellular regulation (see here [nih.gov]).
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You are right about the central dogma. It was formulated in 1958 and states that information flows from DNA->RNA->protein. Since that time it has been ammended many times. Just because it is genereally not true, does not mean it is not useful. For example, Newton's mechanics is generally not true, but it is quite usefull for some applications.
Just running some numbers (based on the abstract)
4 x 10^7 reads * 50 b/read = 2 x 10^9 b.
Error rate (general ballpark for RNA replication/translation, number
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... Newton's mechanics ... is quite usefull for some applications.
Talk about an understatement.
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Evolution really is the ultimate hacker; constantly expanding the usefulness of very simple resources.
"Mother Nature: Überhacker".
That would make a cool tee-shirt!
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One would think that any sensible journalist would be cautious throwing titles like "Central dogma of genetics maybe not so central" with the only scientific publication being a conference lecture [ashg.org].
That's what I thought after reading this ./ post. But then I found (type: "Cheung VG[au] AND Philadelphia" into the search bar)) [nih.gov] that the main author had some respectable publications on the subject.
Even with respectability of the authors of the original publication established, the sensationalist title in Science
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Scientists sometimes use "dogma" in a sarcastic manner. As others have pointed out, this dogma is not so much a "universal rule" as it is "a general guideline with more exceptions than you can shake a stick at."
Stephen Jay Gould talked about the dogma of gradualism. To hear him tell it, evolutionary biologists were telling the fossils that, no, they couldn't possibly be identical to their ancestors from hundreds of thousands of years prior, they had to have made some mistake in where their bones became bu
Why is this news? (Score:5, Informative)
We have known for many years that the same DNA codes to different proteins, with the adjustments given the information in the non-coding regions AND the information in the epigenome. That people have discovered that the intermediate step is also adjusted can hardly be called a shock. The proteins have to get built differently somehow, so some alteration in the intermediate coding was inevitable. Honestly! If geneticists aren't even reading their own bloody papers, maybe the government grants should be issued to those Slashdot readers who do.
Re:Why is this news? (Score:5, Funny)
Honestly! If geneticists aren't even reading their own bloody papers, maybe the government grants should be issued to those Slashdot readers who do.
Tell us how you feel. Don't hold anything back. You are in a SAFE environment here... Now, show me on the dolly where the geneticist touched you...
:)
Side note: Totally agree with the comment
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I think you mean, show me on the memory map where the program inappropriately accessed memory.
Re:Why is this news? (Score:5, Insightful)
That people have discovered that the intermediate step is also adjusted can hardly be called a shock.
Yes, it is a shock. The prevailing thought was that the RNA was transcribed faithfully and then that perfect transcript of the DNA was sliced up in strange ways. These people have discovered that the transcript may never have been perfect at all.
Imagine cutting up a loaf of bread: The geneticists were quibbling about how thick the slices were and how to arrange it on the plate, all without paying attention to what kind of bread they used. Now suddenly they've noticed that the recipe for french bread gave them a sourdough loaf while they aren't looking, and it may not be about the slicing as much as about how the right recipe is giving them the wrong thing to cut up.
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Who thought it was perfect? The only people that thought that, I suppose, were high school students receiving a highly idealized version of cellular protein synthesis (sort of like perfect gasses, etc.) No researchers ever thought it was perfect, because it would be all but impossible to create such a perfect system. If there's any revelation here, it's that protein production is more error tolerant than we once thought, but no one since the discovery of DNA/RNA has ever thought that the system was perfe
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The weird thing (from TFA) is that the imperfections aren't we're they're 'supposed' to be.And there are too many of them.
Robin Egg's analogy is pretty good. Let me try a car analogy: You're in a BMW factory, on the input side, all the instructions and parts are geared towards making BMWs - maybe different colors, different hood ornaments or whatever.
Out pop some BMW's as expected. And a couple of Yugos.
Well, no, that's not right. Go with the baking analogy.
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Exactly - there's a difference between getting an occasionally screwed up BMW, with a random seeming defect, and getting an occasional Yugo, or maybe a working Jetpack, or every time the BMW is not to spec it's always because it has only four lug nut shafts on the left rear wheel, and the spacing also adjusts to make them symmetrically placed, rather than you seeing a host of other defects that are theoretically as likely. Or maybe it's something that definitely won't work as well, definitely what would be
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I'm gonna have to work on the car analogy a bit longer.
Re:Why is this news? (Score:5, Interesting)
Well, no. The transcription cannot be faithful because there are more letters in RNA than in DNA. Even if you ignore that aspect, geneticists knew that there was a data-driven transform somewhere. Assuming that it is in point A rather than looking is not the hallmark of a scientist. That is the hallmark of the incompetent. Never, ever extrapolate further than the data will permit on the assumption that the extrapolation is valid. Extrapolation should only ever be done for the purpose of creating a hypothesis. Leave articles of faith to religion. On second thoughts, the religious tend to extrapolate beyond limits too, so that might not help.
Anyways, the fact is that there are only two possible places in which a transform could happen (and it could happen in both). This gives you a total of three possibilities. Now, only the DNA-to-RNA step could include information from the non-coding regions. It's possible that either stage could be effected by the epigenome. From this, it follows that two of the three cases involve the DNA-to-RNA step and two of the three methods involve the DNA-to-RNA step. It may be unexpected, in that they may not have considered that possibility sufficiently, but to call it a shock implies that they ignored the mechanisms entirely -- mechanisms the genetic scientists have been studying in depth for a very long time.
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Just because other research indicated this might be the case doesn't mean that this was previously known. Do you really think it unnecessary to actually determine if your assumptions are correct? I hope you aren't using and government grant money.
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There are four letters in DNA, five letters in RNA. That tells me that something about not copying identically was indeed previously known. The protein encoding was also known for a fact - it wasn't just indicated, it was pretty much accepted by the genetics community as having been sufficiently gone over to be considered standard fare.
The question was WHERE the change happened - DNA to RNA, or RNA to protein? That wasn't established. Two possibilities, one (or both) could be possible. That gives two out of
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The four bases in DNA aren't the same as codons in the code - there are 64 codons set up as triplets of bases in DNA, even though of those, 61 are used to code for only 20 amino acids and the remaining 3 code for a STOP bit. Messenger RNA uses the same number of codons by the model, including also having three ways to express a STOP. There are some already known exceptions, mostly some uncommon organisms use one or two of the three STOP bits to code for an amino acid instead. Incidentally, the START bit (AU
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This is the important part of the article, everything else is comparatively irrelevant:
Not knowing why this is occurring so frequently is what is truly interesting about this, at least from my point of view as a biochemist.
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Now that is very different. Not knowing why is indeed very interesting. The consequence of the misspellings depends on whether they ARE true misspellings versus data-driven modifications from non-encoding genetic material. If they are deliberate transforms, then to call them misspellings is flawed, since the spelling would then be precisely what the DNA coded for (when considering all other types of data). Likewise, when U is used in RNA, it is not considered a mis-spelling, even though that would not be th
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Don't forget, we've known about RNA editing for over a decade now...
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I agree that we've always suspected that transcription isn't a high fidelity process. In fact, there is evidence that leads us to this conclusion (ex. the lack of a 'spell-checker' mechanism). However, just because we have evidence that points to an effect doesn't mean that it shouldn't be tested. The thing is, we've been surprised before. We've had evidence of other phenomena/behaviour should exist but when actually tested, it turned out that it was not as expected. For example, in the past it was thought
Re:Why is this news? (Score:5, Informative)
I don't see why you claim there isn't a spell checker. Using DNA for the long term storage itself increases fidelity over RNA. Putting the DNA in a nucleus to protect it from some chemical processes that can cause data malformation also means an increase in fidelity. Multicellularity means (admittedly among other things), moving the reproductive cells deep in the organism so they are again protected from some more sources of copying errors. Simultaniously, it allows apoptosis (as there's no advantage for cell death in a single celled organism), and that's a second spell checker of sorts for multicelled organisms only. A lot of the more complex organism's defenses against diseases such as cancer could all be described as spell checkers (for example, P53 tumor suppressor). The form of DNA polymerase used in the complex organisms itself improves copying accuracy by about 100fold over what's possible for the non-eukarotes and even some of the fairly complex bacteria, and it's been described in operation as 'wiggling the part it has just put together to make sure it hasn't allowed the wrong base to pair before it moves on to the next bit, and having a digestive capability to strip out such mistakes when it finds them'. (See "Our Molecular Nature", by David Goodsell for more on this). Then there's snRNPs (Small Nuclear Ribonucleoproteins, which are formed to snip out introns from RNA copies for those RNA strands that aren't self splicing ribozymes (and of course rybozymes themselves even in organisms too simple to have snRNPs). It looks to me like most of the major changes in organic complexity are also spell checkers of one sort or another. I don't really like to anthropomorphise evolution as having long term goals, but it's probably at least as fair to say evolution is trying to produce totally accurate transcription, as it is to say it is trying to make organisms more ideally suited to their environments.
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And sexual reproduction also count as a form of spell checking. It allows you to introduce random errors in the DNA, and get back perfect DNA from other individuals when you reproduce. (Muller's ratchet, which to my mind sufficiently explains why we have sexual reproduction, and which I was sad to find that somebody else had thought of before me.)
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The problem is, that Natural Selection requires, in theory, that there be some pretty strong limits on blending. The classic Mendelian model implies a code that is pretty reliably non-blending and that in turn is one of the things that makes NS count as science. That is, it had predictive power - Darwin's original work caused him to predict that when the code was discovered, it would allow, at most, only very limited blending. * "One DNA sequence yields one protein, now and forever" also works to make blend
This is NOT what the central dogma says (Score:3, Informative)
What it does in fact say is that information flows from DNA to RNA to proteins, and not the other way around: proteins can't write DNA.
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But with selective methylation they might as well.
Re:This is NOT what the central dogma says (Score:4, Insightful)
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proteins can't write DNA
Unless that protein is DNA polymerase...
It's called an "error rate" (Score:4, Informative)
When DNA is copied to make new DNA, you get a certain number of copying errors, called mutations - most of them harmless. I assume everyone knows about those.
When DNA is copied to make a temporary-working-copy RNA, you get a larger number of these copying errors because, in general, they are one-shot non-critical deals. The need for stringency is much lower, the selective advantage for stringency is not so great, so it comes as no surprise that the level of proof-reading is also reduced.
Now, it's also possible that there are mechanisms by which these RNA molecules can be purposefully edited. As mentioned in the article, significant post-transcriptional editing (including in eukaryotes the readaction of big chunks, which are called "Introns".) But this finding doesn't speak much to that, although the rate is a *sconch* higher than I might expect for random errors. Even so, this doesn't shake the central dogma of molecular biology in any meaningful way, as for example Reverse Transcriptases did.
Not "errors" (Score:2)
RTFA. These are not errors. They happen the same way in every strand of RNA.
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If it's consistent, would it not be selected for and therefore not really an error at all?
Once an error becomes fundamental to the system, it's not an error.
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Not to mention that a whole bunch of stuff happens between transcription (DNA -> RNA) and translation (RNA -> protein).
The ends have to be capped and modified, in eukaryotes the transcript is only a precursor and has to be spliced into the mature sequence, then the whole thing is exported from the nucleus to the cytoplasm.
Plus there's a whole bunch of stuff happening that we don't really know about, like pseudouridylation and methylation of specific sites.
Not to mention, there's always the good
Slashdot (Score:5, Funny)
News for nerds who never took a biology course and are deeply suspicious of the so-called "sciences"
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News for nerds who never took a biology course and are deeply suspicious of the so-called "sciences"
They didn't even read The Economist [economist.com]. In 2007.
Conservative subs or not? (Score:5, Insightful)
I'd be interested to know how conservative these mistakes tend to be. If the mistakes generally replace amino acids with very similar ones it might be a programmed method of prodding just how much variation a structure can take while remaining functional. Weird and random events, which can be only so weird and so frequent before everything breaks entirely, are necessary for evolutionary adaptation, and these weird protein errors might be a previously unknown mechanism of exploring slightly different structures for proteins and seeing how far an organism can push the envelope.
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I'd be interested to know how conservative these mistakes tend to be.
They must be very conservative.
I've been seeing a lot of mistakes among the Tea Partiers.
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No Surprise (Score:2, Insightful)
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Engineers are probably the absolute worst people to be judging complex biological processes like reproduction. In fact, even during meiosis and mitosis, there are all sorts of flaws. It's one of the driving forces of evolution, creating at least a certain fraction (just what that is is still up for debate) of the variation in any population's genome.
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The problem with thinking that way is that these "errors" are not random like transcriptual errors usually are.
Mutations (Score:2)
Thought I read somewhere that when the first cells started to form in the primordial soup they were more RNA than DNA since that gave them rapid mutations, the ability to adapt quickly and evolve.
Later on as Cells and organisms became more complex, DNA took over since it was more stable but mutates / evolves at a slower rate...
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It seems likely that the earliest replicators (they may not even have been cells, per se) probably did not use RNA and DNA at all. RNA would have been a somewhat later innovation, like lipids being used to produce simple membranes to create a semi-permeable barrier to protect replication and protein synthesis. At that point we would have had simple cells.
Re:Mutations (Score:4, Informative)
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That's not my understanding. RNA world is not the starting point, but at some point further along. But perhaps we need to clarify the terminology. The most primitive replicators may not have been life in the sense that we apply.
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DNA definitely has a lower mutation rate. That doesn't mean it evolves more slowly. Complex species actually seem to give way to new species more rapidly than simpler ones. There's some arguments that a high enough mutation rate actually slows evolution down:
1) Most mutations are bad
2) Of the few that are good, most give only a small improvement, since most organisms are pretty well adapted to their environments.
3) So a successful mutation usually means an organism has on average, say 1.01 offspring while i
Wind DNA gradyooate? (Score:4, Funny)
Thanck God! (Score:4, Funny)
nearly 4,000 genes in which the RNA copies contain misspellings
I new my bad speling wasnt my falt- its just genetic. Finaly I can prove it to my teacher! I hope scientists next fined genes with bad grammar,
Not news. (Score:2, Informative)
From the article: The most common of the 12 different types of misspellings was when an A in the DNA was changed to G in the RNA. That change accounted for about a third of the misspellings.
This is a textbook example of RNA editing by adenosine deaminase. It will convert the Adenosine bases ('A') to Inosine ('I'). When they try to sequence the RNA the first step is to make a DNA copy. During the process the pos
direction of information flow (Score:2)
The 'dogma' concerns the direction of information flow (DNA <-> RNA -> proteins), not about how perfect it is.
More than one way to a result (Score:3, Interesting)
So here's a question.
Suppose that this "error" that happens every time nonetheless yields the same original DNA sequence?
dna half-strand ACTG ----> rna TATTCGAGATATAC ---> dna half-strand ACTG
It's been a very, very long time since I took my college biology, so be kind if I'm wrong. My point is that these might not be "errors" at all, just alternate intermediate steps that generate the same ultimate results. The assumption to date seems to be "one, and ONLY one, amino acid on RNA yields one, and ONLY one, corresponding amino acid on DNA". Is that necessarily the case, every time? I'm quite sure about ohhhh, a billion molecular biologists have already thought about this. I just don't know the answer.
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> Suppose that this "error" that happens every time nonetheless yields the same original DNA sequence?
I'm not convinced your example ACTG ----> rna UAUUCGAGAUAUAC ---> dna half-strand ACTG matches the article [with tyrosine changed to uracil], because it sounds like they're talking about substitutions, rather than insertions, in this article (i.e. ACTG ----> rna TATC (although if substitutions are happening, an insertion/deletion may also be possible).
Anyway, there are certain RNA codons that pr
NO no no, these comments are all wrong (Score:2)
Not so Surprising... (Score:5, Interesting)
The fact that the "errors" are consistent, suggest this is not an error at all. There was a famous experiment utilizing genetic algorithms to build an optimal circuit with the least possible number of components. It was a simple circuit, and the optimal circuit was well understood. It was an attempt to prove that the genetic methodology would quickly yield this optimal circuit. To everyone's surprise, the process yielded a circuit with fewer parts than the theoretically optimal circuit. What the designers of the experiment hadn't taken into consideration was that the genetic algorithm didn't care about theory, only outcome. It had discovered a heretofore unknown capacitive reactance on the closely spaces lines of the experimental circuit board, and found a way to use that capacitance to reduce the number of parts in it's design. Given the nature of the system, evolution found a clever way to engineer around the believed limitations of the experiment, and utilize any and all real world resources to create a solution transcending of the point of view of the experimenters.
Likewise, there's something interesting going on here with the RNA, well outside of the obvious perspective of the researchers. Bring in biochemists, theoretical physicists, and maybe a couple applied organic chemical engineers. Let them figure out what's happening at the quantum and molecular level to have this outcome be the result. Start doing simulations. Look at topologies and protein folding.
Look at CJD (Creutzfeldt-Jakob Disease) or BSE (Bovine Spongiform Encephalopathy) the causative agent is a prion. A vital protein that in its normal state is essential to neurological function, which can fold in more that one way, and folded the wrong way destroys brain tissue and ultimately causes dementia and death. I'll bet dollars to donuts, that there is some funny quantum state, or a protein folding problem, or some simple nonbiological chemical process whose probable result is a code misspelling in protein formation. Its an interesting problem, but not at all surprising. We are complex systems, and trying to force the world processes that make us possible into a box is at once myopic and foolish.
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That reminds me of an anecdote about genetic algorithms that Rick Riolo (U. Michigan) told during a complex systems seminar. He was part of a team in the 80s that was trying to use GA's to find the most fuel efficient autopilot possible for a specific airplane. They configured an industry standard simulation environment with a realistic gamut of weather conditions, etc etc. and left the GA running for a few weeks. When they came back, they were surprised to find all the surviving autopilots had more fuel th
The explanation comes from CS. (Score:2)
RNA actually IS a copy of the DNA. The apparent misspellings are the genetic equivalent of backslash-escaped backslashes and other meta-characters. :)
It's called RNA editing, and it's not new (Score:2)
RNA editing has been known for a long time (Score:2)
That mRNAs are edited post-transcriptionally has been known for some time now. In mammals, RNA modifying enzymes will act on specific mRNAs to alter their base structures, thereby changing their amino acid encoding. (too tired right now to provide a link, but this happens for mRNAs coding for AMPA-class glutamate-gated ion channels). It's not so much that it happens per se that is amazing; its that it happens at this large scale.
Much of this stuff is based on nex-gen high throughput sequencing technology, w
how the hell is this news? (Score:2)
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Agreed. The "news" part is that it's widespread, whereas RNA editing was primarily known to occur in mitochondrial genes before.
This does not invalidate the Theory of Evolution (Score:2)
I thought that I would say that before some religious nutter makes the claim that ''this shows that Darwin was wrong''.
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You've got to bear in mind that researchers have only limited memory. They can't afford the 512Mb brain upgrade with all the funding cuts.
RTFA, the errors weren't random. (Score:4, Informative)
The amazing thing is not that there are mistakes, but the exact same mistakes occur in (almost) every strand of RNA! They aren't random errors, they occur the same way every time!
Re:RTFA, the errors weren't random. (Score:4, Insightful)
That's kind of interesting, but not really amazing. Something must be causing the "mistakes" no matter how "random" they appear to be -- whether it's a virus, a stray cosmic ray or something else. The fact that it seems much less random than you'd expect just points to the likelihood that we'll soon get to the bottom of the phenomenon.
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If strikes by 'stray' cosmic rays are a non-random phenominon, then you've just proved an intelligent super-powerful being deliberately interferes in evolution. I'm glad you think that wouldn't be amazing. Personally, if I'd just proved that, I wouldn't be so blasé. In fact, I'd be demanding the Nobel committee make me Pope and the Roman Catholic church give me a big gold prize, and probably hinting that Ms. Portman should climb out of those grits, towel herself off, and bear my children to get in good
Re:RTFA, the errors weren't random. (Score:4, Funny)
If strikes by 'stray' cosmic rays are a non-random phenominon, then you've just proved an intelligent super-powerful being deliberately interferes in evolution.
True, and if cosmic rays are green, then I've just proven that breakfast cereal is made of oats.
Or to put it another way: If a cosmic ray could strike an RNA molecule and sometimes it would cause a change in the molecule and sometimes it wouldn't, and no observable phenomenon could be used to determine when it would and when it wouldn't, then that would appear to be a random phenomenon. If every single time a cosmic ray strikes the molecule it causes a change, then that is a non-random, cause and effect phenomenon.
Maybe you should have stayed in bed this morning.
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Step 1, check the lab, and make sure THEY aren't making the mistake.
Step 2, check the sample, maybe there's something off about these "27", if they blink with 2 sets of eye lids, you've got your selves an alien!
Disclaimer: This is satire, don't respond about aliens.
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I quoted the word mistakes because I don't believe they are mistakes, just like you say. You're chasing your own tail on this one.
Re:RTFA, the errors weren't random. (Score:5, Informative)
Even that's not amazing. It would be amazing if it made a different mistake every time.
The simple model of transcription had always been that single nucleotides in DNA are matched to the complementary nucleotide on the RNA strand. But, of course, nobody thought the simple model was always correct. You've got the interaction of a DNA strand trying to fold back on itself and an RNA strand trying to fold back on itself, and a big honking RNA polymerase molecule with an extremely complicated electric field. It's to complicated for the simple model to work. Maybe on occasion the order of the codons a few hundred bases from the transcription site will interact with the RNA polymerase to insert a different base than expected. (Just throwing that out as a possibility. It could be any of a million things, like an induced change in the structure of RNA polymerase.) That's fine, as long as it happens the same way every time. In that case it's not an error in the DNA or the RNA. It's an error in our oversimplified model of how RNA transcription works. So now we need a better model that can predict how a DNA sequence will be transcrived. Don't look now, science is working the way it should!
I hate that they are even using the word dogma. Because actually dogma is never based on or swayed by evidence. And in this case the dogma was "it's simpler than any realistic biochemical system." I'd like to see a poll of how many biochemist, molecular geneticists, virologists and microbiologists actually believed this dogma.
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I like your fairy-tale world where scientists aren't fallible like all the people I know. Just one example, which is more public, but probably happens all the time.
Some guy did some experiments and found that a large number of people with ulcers (about 75%) had a certain kind of gut bacteria in their stomach. Moreover, putting them on a course of antibiotics would cure the ulcer. It took the guy 5 years for anyone to take him seriously, and another 5 years or so before it became common practice to check
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As it should. If you are going to make a claim, you'd better be damn sure you have sufficient data to back it up. The whole points is that weak ideas should be rejected.
No, this was science not accepting claims without sufficient data. Once the actual research was done to back up the claims, it was accepted. Just the way it's supposed to work.
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Consistently incomplete doesn't necessarily mean consistently incorrect. Maybe you'd really rather certain portions of the DNA are reliably not transcribed to matching RNA.
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As others have noted, it's apparently not random, but bigger exceptions to the central dogma have been known for decades. I was thinking that the whole title of "central dogma" was an ironic title that we've played up more (though I have no idea the history of the term.) Retroviruses were a huge violation of the rules, going from RNA into DNA. It seems to me like micro RNAs regulating translation of mRNA into protein diddles the rules a bit as well. The "dogma" as described here ("DNA letters encode inf
Central Dogma Barking Up Wrong Tree (Score:4, Insightful)
No, the big thing about this (if indeed it holds up) is that the fidelity is much, much lower than expected. It doesn't seem that the mRNAs are miscoding (although it's possible) it seems that the coding is being jiggered with by other factors.
However, this is a statistical analysis of a number of genomes and the original genome coding teams warns that the precision of the decode may not be enough to warrant TFA's (tentative) conclusion.
But it's interesting and exciting. Stay tuned. Beats politics.
Re:Central Dogma Barking Up Wrong Tree (Score:4, Insightful)
Re: (Score:3, Interesting)
And yes, the old Central Dogma is getting a bit frayed at the edges given all the newfangled RNAs they seem to discover monthly. That's the fun part.
Re: (Score:2)
It also means that incredible amounts of mRNA work is being done, despite faulty proteins, successfully. The error rates inferred seem to be extraordinarily high, yet things succeed.... probably as they should. Therein lies the crux of voluminous questions about *why*.
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Maybe all that "junk data" encoded in our genes is really a permittable margin of error.
Think like a disc with 10GB of capacity. If you have several hundred megs of bad sectors but only a gig of data to store, a smart enough operating system would probably be able to avoid the damaged areas.
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Spot on. The error here is in our knowledge of what's happening, our RNA is functioning as intended.
OK you people (Score:2)
I can't jump in with an angry post picking abort your posts if you keep acting so reasonable.
Where are the logical fallacy's? where is the unjustified rants?
Sheesh, what has slashdot become?
Re: (Score:2)
...and the "grocer's apostrophe's".
You'd think the fidelity would be perfect (Score:2)
Re:NEWS FLASH (Score:5, Insightful)
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You could have saved them from publishing such garbage!
The correct phrase is, "You could have advised them of additional observations pertinent to their investigation that would be useful to report as well." Publishing results of investigations should be encouraged, regardless of the perceived uselessness of the results and the sillyness of the investigator's conclusions.
If the conclusions are thoughtless, then other people have an opportunity to make a name for themselves by reviewing the investigation and identifying alternative ways to interpret the data.
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