Does DNA do this?

R

Robittybob1

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Has anyone heard of double sided DNA strands.
Now you are laughing!
But what I mean is that both sides of the DNA double helix has code. One side of the strand obviously is the main code of the gene, but could the opposing strand also be a code? Or even multicoded depending on the stop starting point of the DNA sequence?
i.e. same code produces more than one enzyme depending on how it is read? It would be bizarre but not impossible, wouldn't it?
So the DNA might not increase but the efficiency of the system is increase by multicoding, e.g. CD compared to DVD -multi layers on a similar sized piece.

Could this ever happen or is it too difficult?
 
I don't think so, one of the main purposes of DNA's double helix is that when a cell divides it gets half a Helix (which then becomes double again), if you remove the pair bonding you remove the ability for cell division.
 
Asguard said:
I don't think so, one of the main purposes of DNA's double helix is that when a cell divides it gets half a Helix (which then becomes double again), if you remove the pair bonding you remove the ability for cell division.
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I found the relevant section on Wikipedia.
This is really interesting.

http://en.wikipedia.org/wiki/Transcription_(genetics)
Transcription (genetics)
“Although DNA is arranged as two antiparallel strands in a double helix, only one of the two DNA strands, called the template strand, is used for transcription. This is because RNA is only single-stranded, as opposed to double-stranded DNA. The other DNA strand is called the coding (lagging) strand, because its sequence is the same as the newly created RNA transcript (except for the substitution of uracil for thymine). The use of only the 3' → 5' strand eliminates the need for the Okazaki fragments seen in DNA replication.”

So even though there are two strands only 1 has the genes on it. :)
 
err no, thats not what that means. It means only 1 strand is used at a time but when the cells divide they BOTH get used, the DNA divides and gets reincoded so there are now 2 identical DNA strands, the cell splits, half the mitocondria go into each and 1 of the NEW DNA strands goes into each cell
 
Asguard said:
err no, thats not what that means. It means only 1 strand is used at a time but when the cells divide they BOTH get used, the DNA divides and gets reincoded so there are now 2 identical DNA strands, the cell splits, half the mitocondria go into each and 1 of the NEW DNA strands goes into each cell
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Yes and no. We are talking of different operations Transcription is prior to forming RNA from the DNA strand, but in this case it says only ever 1 side of the double helix.
Where as in cell division there needs to be two copies of the DNA double helix
So in this case both sides are copied as you describe.:)
 
if you encode different data on each strand then when the cell divides different DNA will be present in each cell and you will go back to 2 identical strands in the cells (though different BETWEEN cells)
 
But what I mean is that both sides of the DNA double helix has code. One side of the strand obviously is the main code of the gene, but could the opposing strand also be a code? Or even multicoded depending on the stop starting point of the DNA sequence
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The code is not contained on one side of the double helix. It is contained on both sides from the very get go. The double helix provides a way that two strands, one from each parent, can be combined in order form the "new" code. Watson and Crick were the first to recognize this, in their wonderfully understated comment in their 1953 article announcing the discovery of the helical structure of DNA: "It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material."

Rich
 
The two strands are complementary. This is necessary for transcription to work.

The lagging strand you are referring to which also carries a code does not carry any new information. It carries the same information, codon by codon, in the negative sense.

The lagging strand serves to cap the leading strand between cycles. In this manner particular genes can be unzipped one at a time. Otherwise the whole strand would be exposed and there would be no meaningful way to perform replication.

It's not new information, just the same old information in reverse polarity.
 
Aqueous Id said:
The two strands are complementary. This is necessary for transcription to work.

The lagging strand you are referring to which also carries a code does not carry any new information. It carries the same information, codon by codon, in the negative sense.

The lagging strand serves to cap the leading strand between cycles. In this manner particular genes can be unzipped one at a time. Otherwise the whole strand would be exposed and there would be no meaningful way to perform replication.

It's not new information, just the same old information in reverse polarity.
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Well do you agree with Wikipedia on the subject that only one strand has the necessary code for the genes. The other is the lagging strand which never gets read in the process of producing RNA, in the step toward producing proteins etc.
None of the posts above have referred to RNA yet and seem only focussed on DNA replication. Which is something we agree on.

Both sides are read during DNA replication but only one side is read during RNA synthesis.
Is that correct?
 
DNA contains two strands called the "sense" strand and the "antisense" strand. Only the sense strand codes for proteins, but the antisense strand is used to reproduce the sense strand's information in mRNA, which codes for protein.

Consider this sculpture casting analogy.

The "sense" strand contains the genetic information, like a sculpture contains information. What I mean is, you can see the nucleotide sequence in the sense strand that codes for the amino acids that constitute the protein. If ribosomes were to read the DNA directly to produce proteins, they would do so from the DNA's "sense" strand.

But cells don't directly use DNA to produce proteins; they use mRNA that's produced from a complementary method. You don't cast a reproduction from a sculpture; you make it from the sculpture's cast. And so, the sense strand has its "antisense" strand (that is, its "cast"), and from the antisense strand, the cell makes mRNA (a reproduction of the sense strand's information), and so, the mRNA codes for the protein.
 
Cifo said:
DNA contains two strands called the "sense" strand and the "antisense" strand. Only the sense strand codes for proteins, but the antisense strand is used to reproduce the sense strand's information in mRNA, which codes for protein.

Consider this sculpture casting analogy.

The "sense" strand contains the genetic information, like a sculpture contains information. What I mean is, you can see the nucleotide sequence in the sense strand that codes for the amino acids that constitute the protein. If ribosomes were to read the DNA directly to produce proteins, they would do so from the DNA's "sense" strand.

But cells don't directly use DNA to produce proteins; they use mRNA that's produced from a complementary method. You don't cast a reproduction from a sculpture; you make it from the sculpture's cast. And so, the sense strand has its "antisense" strand (that is, its "cast"), and from the antisense strand, the cell makes mRNA (a reproduction of the sense strand's information), and so, the mRNA codes for the protein.
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I think you are close and I might have accepted your answer except you didn't give me a reference to another reviewed document to confirm what you say.
References please.
 
Robittybob1 said:
give me a reference to another reviewed document to confirm what you say. References please.
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Wow, you're tough.

I note some ambiguity when papers and articles talk about the verb "coding" or that DNA "codes" for a certain protein (as it does in the Medicine.Net article). In a way, both strands "code" for protein. The sense strand has the code, the antisense strand is the template that has the complementary code (that is, the "anti-code"), and the mRNA has the code, which the ribosomes read to produce the protein. Some say that the antisense strand "codes" for protein because it produces the mRNA. Yet, the complementary code on the antisense strand would not exist if it was for the sense strand.

Here's a few sources:

Antisense @ Medicine.Net

Antisense @ Wikipedia

Sense @ Queen's University

Template vs Coding Strands @ San Diego State University
 
Cifo said:
Wow, you're tough.

I note some ambiguity when papers and articles talk about the verb "coding" or that DNA "codes" for a certain protein (as it does in the Medicine.Net article). In a way, both strands "code" for protein. The sense strand has the code, the antisense strand is the template that has the complementary code (that is, the "anti-code"), and the mRNA has the code, which the ribosomes read to produce the protein. Some say that the antisense strand "codes" for protein because it produces the mRNA. Yet, the complementary code on the antisense strand would not exist if it was for the sense strand.

Here's a few sources:

Antisense @ Medicine.Net

Antisense @ Wikipedia

Sense @ Queen's University

Template vs Coding Strands @ San Diego State University
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Hey, you have done well to get back to me on this but did you see anything that would suggest the sense strand would ever at some point along it's length change its role to become an antisense strand.
Or is it determined at the commencement of the strand - Codon reading: "this is the antisense strand" and the other strand "this is the sense strand. Read me please"
 
Robittybob1 said:
Well do you agree with Wikipedia on the subject that only one strand has the necessary code for the genes. The other is the lagging strand which never gets read in the process of producing RNA, in the step toward producing proteins etc.
None of the posts above have referred to RNA yet and seem only focussed on DNA replication. Which is something we agree on.

Both sides are read during DNA replication but only one side is read during RNA synthesis.
Is that correct?
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Do you accept that the two strands are complementary (opposites)?

One is the negative of the other. Regardless of how the codons are retrieved, the information is the same. One is positive (a photograph) the other is the negative image (film). See the connection? The film from a picture of my face will not produce an armadillo no matter how hard you try. It's the same information, no matter how hard you search to find something new there.

I understood that this was your question, which is why I answered it the way I did.
 
Aqueous Id said:
Do you accept that the two strands are complementary (opposites)?

One is the negative of the other. Regardless of how the codons are retrieved, the information is the same. One is positive (a photograph) the other is the negative image (film). See the connection? The film from a picture of my face will not produce an armadillo no matter how hard you try. It's the same information, no matter how hard you search to find something new there.

I understood that this was your question, which is why I answered it the way I did.
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Yes I understand what you say, but the RNA produced from the wrong strand won't produce a viable protein. So it is important for life to know which strand to use otherwise our bodies would be filled with useless proteins.
You agree with that?
 
Aqueous's use of a photograph and its negative is an excellent analogy.

You mentioned the cell needing to know the correct strand to transcribe into mRNA, otherwise resulting in copious amounts of useless proteins. The reality is that the means always exists to produce mRNA directly from the sense strand, but that the vast majority of a sense strand does not produce mRNA.

I did find an article the other day (that I can't locate now) about very small amounts of RNA produced directly from the sense strand although the authors didn't know the use of that RNA (and if the were coding RNA {that produce proteins} or noncoding RNA {that do not produce proteins}).
 
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This preference for the DNA sense strand appears to be very much analogous to the single stereo handedness of biomolecules. For example, active proteins tend to be left handed helixes. The right handed versions of the same proteins tend to be inactive or much less active. There is an energy difference.

This suggests that the DNA double helix has two complemetary strands that are at different potentials. This inference is based on the observation that the sense strand primarily makes RNA, while both strands will make DNA. These two different template reactions are at different potentials.

If we compare RNA to DNA, the DNA is more reduced since the sugar moiety of the DNA has a H atom where the sugar of RNA has an -OH group. There is also a base difference, where a base of DNA has an extra -CH3 group. This extra reduction of the base and sugar of DNA, adds extra surface tension in the water. This will push the DNA into the double helix. The RNA has less reduction and less surface tension and can exist as single or double helixes.

As such, when DNA is being replicated, the extra reduction potential within the monomers of DNA, by increasing the surface tension within the local water, adds the extra potential needed to make full use of the less active anti-sense strand. Without this extra surface tension (RNA monomers) only the sense strand normally is at the correct potential to become the template.
 
Cifo said:
DNA contains two strands called the "sense" strand and the "antisense" strand. Only the sense strand codes for proteins, but the antisense strand is used to reproduce the sense strand's information in mRNA, which codes for protein.

Consider this sculpture casting analogy.

The "sense" strand contains the genetic information, like a sculpture contains information. What I mean is, you can see the nucleotide sequence in the sense strand that codes for the amino acids that constitute the protein. If ribosomes were to read the DNA directly to produce proteins, they would do so from the DNA's "sense" strand.

But cells don't directly use DNA to produce proteins; they use mRNA that's produced from a complementary method. You don't cast a reproduction from a sculpture; you make it from the sculpture's cast. And so, the sense strand has its "antisense" strand (that is, its "cast"), and from the antisense strand, the cell makes mRNA (a reproduction of the sense strand's information), and so, the mRNA codes for the protein.
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Good example .
 
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