A question about translation

[l07971]

If you place a DNA of a mouse, mRNA of a rabbit, ribosomes of a hydra and tRNA of a human in a test tube, and place it in optimal conditions for translation to occur, which imitate the conditions inside cell cytoplasm, you will get a polypeptyde chain of which animal: mouse, rabbit, hydra or human?

Edited June 11, 2013 by l07971

[Brett Nortje]

If you place a DNA of a mouse, mRNA of a rabbit, ribosomes of a hydra and tRNA of a human in a test tube, and place it in optimal conditions for translation to occur, which imitate the conditions inside cell cytoplasm, you will get a polypeptyde chain of which animal: mouse, rabbit, hydra or human?

Well, it should come down to which is stronger, or, more simple! the simpler a thing is the better it will spread, as, it is less complex, and makes it easier to consume the whole thing into itself, you could say.

 

Of course the more advanced or intricate things will fall by the way side, as, they are too 'brittle,' and fragile. Maybe the only way you will know for sure is to go and do it!

[l07971]

Brett, I'm afraid it's more complicated that that, but thanks anyway.

 

I think it depends on the way the process of translation works.

I think the polypeptyde chains will be those of a mouse, because its DNA was "transcribed" onto the mRNA, but I could be wrong. That's why I'm asking...

[Brett Nortje]

Brett, I'm afraid it's more complicated that that, but thanks anyway.

 

I think it depends on the way the process of translation works.

I think the polypeptyde chains will be those of a mouse, because its DNA was "transcribed" onto the mRNA, but I could be wrong. That's why I'm asking...

Maybe if you observe the health of the thing, or, the natural way the cells in the blood divide of the natural thing?

[CharonY]

Well, sounds like homework, so let me ask you this: if you have a polypeptide, how would you know of which origin it is?

Based on that, what is the proximate element that determines it?

How far is DNA away from that point and what is needed for your answer to be true?

[l07971]

Well, sounds like homework, so let me ask you this: if you have a polypeptide, how would you know of which origin it is?

Based on that, what is the proximate element that determines it?

How far is DNA away from that point and what is needed for your answer to be true?

 

That's because it's one of the questions for preparing for those that wish to study molecular biology on college. It's for my friend, who's about to go to university this year.

I'm going to university this year too, but physics, so I'm not THAT familiar with genetics.

 

I thought it would be mice proteins, since the "instructions" for them must come from the only DNA in the test tube.

 

About your questions, I'm not sure I can answer them.

[CharonY]

Well from your answer I gather that you are not quite familiar with the whole process of protein biosynthesis. You have to thing your way through from DNA to protein and see where the bits and pieces come together. Hint: read up transcription.

 

Thinking in rough terms such as instructions obscure the mechanisms behind it and won't allow you to understand the process.

[l07971]

Well from your answer I gather that you are not quite familiar with the whole process of protein biosynthesis. You have to thing your way through from DNA to protein and see where the bits and pieces come together. Hint: read up transcription.

 

Thinking in rough terms such as instructions obscure the mechanisms behind it and won't allow you to understand the process.

 

Actually, I think I understand the basics:

> The DNA gets unwind and the mRNA is synthetised next to the DNA bases from complementary bases.

> Then mRNA leaves the nucleus and goes to ribosomes where it attaches to the smaller subunit (not sure, though).

> tRNA "brings" the amino-acids which "fit" to mRNA 3-base code (anti-codon, I think)

> These amino-acids get polymerised by enzymes and detach from ribosomes.

> This chain then gets twisted and what not to get the fully functional protein.

 

I'm sure it's oversimplified, but I think I got the gist.

 

This is why I think the final proteins will be "mice proteins", since they must hae been created according to "mouse DNA" instructions.

[CharonY]

Think more carefully, especially in terms of what what is present in the test tube. What do you need from to go from DNA to mRNA? And again, check what is already there...

[l07971]

Think more carefully, especially in terms of what what is present in the test tube. What do you need from to go from DNA to mRNA? And again, check what is already there...

 

Well, I think that, normally, mRNA is synthetised from free nucleotides, present in the nucleus of the cell, i.e. adenine, guanine, etc.

However, since I dont think there are free nucleotides in the test tube, they must come from some "dissolved" polynucleotide chain, but which..? (rabbit mRNA, human tRNA ?).

But even so, aren't the nucleotides of different species the same? Why would it matter if it comes from a rabbit or human? It will still be adenine in mRNA, where thymine was in DNA.

 

Anyway, I wanted the get the answer somewhat quickly, however it didn't go that way. I feel like I'm taking molecular biology course myself.

At least it was fun.

Thanks.

[CharonY]

Well, quick answers generally do not help in understanding the subject as evidenced here (you are still missing crucial elements that you need to know to derive the answer), but you are certainly welcome.

[l07971]

I understand why you don't give quick answers, as that way the one who questions learns nothing and just lies to himself that he understands the subject.

However, as I said, this question isn't for me, and I would have prefered if you had given me a "simple" answer, rather than 5 answers.

By "simple" answer I didn't mean "a) mice polypeptid", but rather something like "human DNA gets unwind and mRNA is synthetised from certain nucleids, etc.".

[CharonY]

DNA-dependent RNA polymerase

[l07971]

I know I'm annoying, but is this the final answer or a "hint"?

 

I know that RNA polymerase is an enzyme which initiates the "transcription" process. Since it's dependant on DNA, would that mean that the final result will be "mouse polypeptides" (mouse DNA was in the test tube)?

[CharonY]

It is still a rather obvious hint I will give you one answer, your assumption is wrong. It is not mouse. RNA polymerase does not initiate transcription (other enzymes are involved initiation), but it does the actual transcription. According to the opening question, if you look at the enzymes listed, do you see something missing?