The DNA, RNA and Proteins
Although DNA stores the information for protein synthesis and RNA carries out the Messenger RNA (mRNA) is translated into protein by the joint action of . Likewise, each of these enzymes links one and only one of the 20 amino acids to a. The mRNA specifies, in triplet code, the amino acid sequence of proteins; the code is then Citation: Clancy, S. & Brown, W. () Translation: DNA to mRNA to Protein. .. Nature , – () doia0 (link to article). The second relationship is that mRNA uses DNA as it's template or pattern. the mRNA is translated into proteins according to the sequence of the bases.
So for example this might be a section of a much longer molecule, so the much longer strand of DNA, and even there I'm probably not giving justice to it. But this might just be this very, very small section, let me do this in a different color, this little section right over here, zoomed in.
So once again it might be part of a molecule that has not seven or eight base pairs, but might have 70 million base pairs. So just like that. So let's understand what a molecular basis of heredity would need to do. Well first of all it would need to be replicable. Or we would need to be able to replicate it. As a cell divides, the two new cells would want to have the same genetic material. So how does DNA replicate? And this process is called replication. And we covered this in the introduction video as well, but it's nice to see the different processes next to each other.
And replication, you can imagine taking either splitting these two sides of the ladder, and actually let's do that. So let me copy and paste, so if I take that side right over there, so let me copy and then paste it. And then there we go, a little bit of it is dropping below the video but I think that serves the purpose. And then let's copy and paste the other side.
The Three Roles of RNA in Protein Synthesis - Molecular Cell Biology - NCBI Bookshelf
So let me select that. And then I copy and then I paste, and it's just like that. And so you can imagine if you were to split these, these things you could call them two sides of the ladder, that either side could be used to construct the other side.
And then you would have two strands, two identical strands of the DNA. And so let's see what that actually looks like. So let me get my pen tool out now, let me deselect this, get the pen tool out. It's a new tool I'm using, so let me make sure I'm doing it right. Alright, so from this side, from this left side, or at least what we are looking at as the left side, you can then construct another right side based on this information.
A always pairs with T if we're talking about DNA. So adenine pairs with thymine just like that. Thymine pairs with adenine Let me do that a little bit neater.
Thymine pairs with adenine, guanine pairs with cytosine, cytosine pairs with guanine, falling a little bit down here. And just like that I was able to construct a new right hand side using that left hand side. So maybe I'll do the new sugar phosphate backbone in yellow.
And we can do the same thing here using the original right hand side. So using the original right hand side, once again the T is paired with the A, let me do that in adenine's color.
So we have an adenine and thymine, adenine and thymine, adenine and thymine. Thymine pairs with adenine, so thymine, adenine. Guanine pairs with cytosine.
And then cytosine pairs with guanine. So cytosine just like that. And so you can take half of each of this ladder, and then you can use it to construct the other half, and what you've essentially done is you've replicated the actual DNA. And this is actually a kind of conceptual level of how replication is done before a cell divides and replicates, and the entire cell duplicates itself.
DNA replication and RNA transcription and translation
So the next thing you're probably thinking about, "Okay, well it's nice to be able to replicate yourself "but that's kind of useless if that information can't be "used to define the organism in some way "to express what's actually happening. DNA anti-sense strand template for transcription 5' However the genes in a bacterial DNA do not have the same directionality, so one can and should only talk about the sense strand of the DNA specifying a particular gene.
Coding strand In your original question you switched from talking about the sense and antisense strands to talking about coding and non-coding DNA strands, although you later removed this. I would argue against this usage. It is the mRNA that does the coding and is actually translated into protein.
The DNA can only be regarded as sense or not in terms of conceptual translation. In practice it either serves as the template for transcription or its complement does. In English the term template generally means a pattern, mould or former used as a guide to create objects of a similar shape.
Its adoption to the molecular biology of nucleic acids involved a subtle change of meaning, as the article produced from the DNA template the product strand — DNA initially was not the same shape as the mould, but a complement to it. However, the complementarity rules of the bases meant that the information in the original was preserved in a manner somewhat analagous to that of a printing plateand the metaphor caught on as it conveyed a clear meaning.
I show the protein strand as a linear line, but in reality complex interactions between amino acids lead to 3 dimensional forms that are essential for the functioning of the protein. During this translation, 1 amino acid is added to the protein strand for every 3 bases in the RNA.
So a RNA sequence of 48 bases codes for a protein strand of 16 amino acids. A certain combination of 3 bases always gives the same amino acids, so we can put the translation into a table see below.
We take the first 3 bases from the figure above as example, which are AUG.
From DNA to RNA to protein, how does it work?
There we see our third base and our combination. In this way we can translate the complete RNA sequence into the protein sequence. In the cell But how does this work in an actual cell? And why make RNA first and then protein? Why not make protein from the DNA directly?From DNA to protein - 3D
After transcription the RNA is relocated to the cytoplasm of the cell, here it is translated into protein. So the separation of nucleus and cytoplasm prevents protein from being made directly from DNA. But there are other reasons why RNA is made.