How is a gene for a particular protein inserted into a plasmid?

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Accepted Answer

All right. Hello everyone. So this question is asking us which of the following accurately describes how a gene for a specific protein gets inserted into a plasma. Option. A says the gene is spliced directly into the plasmid using hydrogen bonds. B says restriction enzymes cut the plasmid and the gene and DNA ligase seals the gene into the plasmid. C says the gene is inserted into the plasmid through ionic interactions between the nucleotide sequences. And option D says RN a polymerase inserts the gene into the plasmid during transcription. So given the context of the question that we're given, right. This particular question is talking to us about a concept known as recombinant DNA or really a technique. So recombinant DNA is a technology used to introduce a gene from one organism into the DNA of another, usually a bacterium. Now, the reason why this happens is to force that bacterium to synthesize a protein that it itself does not normally contain. For example, we use recombinant DNA to mass produce insulin which is not normally produced by a bacteria without this modification. So to insert a gene into a particular bacterium, we do so via plasmid So let's talk about the steps in which this happens. The first step of course is to isolate the gene of interest, right? And the way this is done is by what are known as restriction enzymes. Now, restriction enzymes, if you recall are unique because they are selective for specific DNA sequences. So once the enzyme recognizes that particular sequence, it can be cut out of the original sequence allowing for that specific gene to be isolated. So now that you have the gene in question, you move on to the next step, which is to prepare the plasmin. Now the plasmid is how the DNA or rather how the gene is going to enter the bacterium in the first place. So it's important to get that ready first, right. So here that plasma vector is going to be cut, that plasma DNA is going to be cut with the same restriction enzymes. We used to cut the gene of interest. And the reason why we do this is to set up for the third step, which is to insert the gene of interest into the plasma. And so once the gene has been mixed with the plasma itself, those two DNA sequences are combined together with DNA ligase. So the reason why the first step was important was to make sure that the plasmid and the gene in question can actually be ligated to make sure they're compatible. So from here we move on to the fourth step which is the transformation of the host. In this case, oftentimes a bacteria oops, all right. So in this step, the idea now is to introduce the plasma that we just made into the bacteria itself. So here there are a few different ways to introduce DNA into a bacteria. An example is for example, heat shock or electroporation. In any case, after the fourth step, this plasma vector is going to enter the the bacterium with the gene of interest inside of it. So from here, right, it's difficult to necessarily tell which bacteria have taken up the plasmid and which ones have not. Right. So the fifth step is selection for those bacteria that have been transformed. In other words, those that have taken up the plasmin. So what I haven't mentioned previously is that oftentimes the plasmid vector has a gene such as antibiotic resistance. And so the reason why this matters is that during the selection step, what you do is treat the bacteria with that particular antibiotic. And so the bacteria that survive have taken up the plasmid because they were resistant to that particular antibiotic. So from there, we have our final step which is to screen four the gene of interest. And so what that means is that using techniques such as PC R restriction digestion or sequencing, you confirm that the plasmid in the bacteria contains the gene of interest to make sure that the experiment was successful. So now what is the big picture, right. Well, the big picture is that a gene encoding a specific protein is inserted via a plasmid into the host. In question, in most cases, that's a bacterium. So that gene is encoded into the plasmid using a restriction enzyme followed by DNA ligase to combine those two things together into one plasmid vector. And so once the bacteria have been transformed, they can continue to proliferate and synthesize that particular protein now that it has the gene. So now what is the correct answer? Well, the correct answer would be option B as in boy, in the multiple choice because to describe how a gene for a specific protein gets inserted into a plasmid, you would have restriction enzymes, cut the plasmid and the gene and DNA ligase seals the gene into the plasmid. So there you have it. And with that being said, thank you so very much for watching. And I hope you found this helpful.

How is a gene for a particular protein inserted into a plasmid?

Verified video answer for a similar problem:

Key Concepts

Gene Cloning

Plasmid Vectors

Restriction Enzymes and Ligation