BIOLOGY QUESTION

[MrCodeDude]

Effects of Gene Mutations on Protein Synthesis

Procedure:
1. The following sequence is a small segment of one of the two strands oa hyprothetical DNA molecule. Attach the complimentary bases to the sequence under each letter.

strand 1 -- A T G A A T G C C A C T A G G A G T G G T T C G C A C T A G
strand 2 -- T A C T T A C G G T G A T C C T C A C C A A G C G T G A T C

Strand two is my answer, I'm VERY sure it is correct.

2. Using strand 2, transcribe the base sequence that would appear on an mRNA strand

This is where my question comes in, do I just need to change the T's to U's or make an opposite for Strand 2?

Should the answer start off like:
choice #1: A U G A A U G C C
choice #2: U A C U U A C G G

That's my question, sorry, but I'm not sure if I should reverse strand 2 or leave as is and just change all the thymines to uracil's.
-- mrcodedude

 

[Bitek]

It should be choice 1 bc the RNA transcriptase will match the RNA nucleotides to the DNA strand in order to create specific binding. ie the RNA strand will complex with the DNA strand during nucleotide addition, so the basepairs must be complementry.

Oh and btw, a good way to double-check the answer is to ensure that the first codon of the mRNA codes for methionine, or it isn't a viable strand of mRNA (unless you have an ass of a teacher)

 

[MrCodeDude]

Bah, I don't like this
-- mrcodedude

 

[McPhreak]

<< It should be choice 1 bc the RNA transcriptase will match the RNA nucleotides to the DNA strand in order to create specific binding. ie the RNA strand will complex with the DNA strand during nucleotide addition, so the basepairs must be complementry.

Oh and btw, a good way to double-check the answer is to ensure that the first codon of the mRNA codes for methionine, or it isn't a viable strand of mRNA (unless you have an ass of a teacher) >>



Yeah, what he sez. the RNA should look like strand 1 with T's swapped out for U's.

 

[MrCodeDude]

Hafen, the thing that throws me off. Is then after a few other problems, it ends with Methionine and begins with Tyrosine but has a "Stop" in the middle. The problem is, it says "is a small semgent" so it's not the whole DNA strand. Is it possible to have a "Stop" in the middle of a sequence?
-- mrcodedude

 

[imported_vr6]

yep it would have to be choice one.

 

[McPhreak]

<< Hafen, the thing that throws me off. Is then after a few other problems, it ends with Methionine and begins with Tyrosine but has a "Stop" in the middle. The problem is, it says "is a small semgent" so it's not the whole DNA strand. Is it possible to have a "Stop" in the middle of a sequence?
-- mrcodedude >>



what's wrong with a stop codon in the middle of the strand? it's just truncated.

 

[MrCodeDude]

Alright, let's go one step further. Perhaps I made a mistake later on:

The answer to #2 would be:
mRNA base strand -- A U G A A U G C C A C U A G G A G U G G U U C G C A C U A G

3. Group the mRNA sequence into its individual codons.
AUG, AAU, GCC, ACU, AGG, AGU, GGU, UCG, CAC, UAG

4. Now translate the mRNA codons into the tRNA anticodon sequence
UAC, UUA, CGG, UGA, UCC, UCA, CCA, AGC, GUG, AUG

5. Use your text (book) and list the order of amino acids in the mRNA fragment.
Tryosine, Leucine, Arginine, STOP, Serine, Serine, Proline, Serine, Valine, Methionine

That's it, the other questions are on different strands.
-- mrcodedude

 

[McPhreak]

<< Alright, let's go one step further. Perhaps I made a mistake later on:

The answer to #2 would be:
mRNA base strand -- A U G A A U G C C A C U A G G A G U G G U U C G C A C U A G

3. Group the mRNA sequence into its individual codons.
AUG, AAU, GCC, ACU, AGG, AGU, GGU, UCG, CAC, UAG

4. Now translate the mRNA codons into the tRNA anticodon sequence
UAC, UUA, CGG, UGA, UCC, UCA, CCA, AGC, GUG, AUG

5. Use your text (book) and list the order of amino acids in the mRNA fragment.
Tryosine, Leucine, Arginine, STOP, Serine, Serine, Proline, Serine, Valine, Methionine

That's it, the other questions are on different strands.
-- mrcodedude >>



I don't know my amino acids off the top of my head, but are you sure you're listing the AA of the mRNA and not the tRNA?

edit: actually, I don't even need to know them. I know methionine is AUG so I know for a fact you are translating the wrong RNA.

 

[MrCodeDude]

I don't get what you're asking.

Are you saying when I translate the mRNA codons to tRNA I'm supposed to keep it the same?
-- mrcodedude

 

[MrCodeDude]

<< I don't know my amino acids off the top of my head, but are you sure you're listing the AA of the mRNA and not the tRNA?

edit: actually, I don't even need to know them. I know methionine is AUG so I know for a fact you are translating the wrong RNA. >>


Oh, I get it. Thanks man, I translated the tRNA instead of the mRNA
-- mrcodedude

 

[Bitek]

<<

<< Hafen, the thing that throws me off. Is then after a few other problems, it ends with Methionine and begins with Tyrosine but has a "Stop" in the middle. The problem is, it says "is a small semgent" so it's not the whole DNA strand. Is it possible to have a "Stop" in the middle of a sequence?
-- mrcodedude >>



what's wrong with a stop codon in the middle of the strand? it's just truncated. >>



Lemme think, its been a while since I've had to do this...

in order to translate an RNA into protein it must start with a meth. ...so the sequence by itself seems worthless..and yeah I think a stop codon in the middle would create a truncated protein anyway.

What does it mean by "small segment?" Is it a finished mRNA molecule or a RNA molecule that has yet to have the exons removed? This may create a frameshift but would not help the first codon (unless the sequence started with an exon.) This is about as much help as I can offer without seeing the problem set. I

t may be just a stupid question, or something trickier that I'm not seeing in the info you've given me.

Edit: Ok nevermind didn't finish my reply before you posted the other info. Looks good now.

 

[McPhreak]

<<

<< I don't know my amino acids off the top of my head, but are you sure you're listing the AA of the mRNA and not the tRNA?

edit: actually, I don't even need to know them. I know methionine is AUG so I know for a fact you are translating the wrong RNA. >>


Oh, I get it. Thanks man, I translated the tRNA instead of the mRNA
-- mrcodedude >>



No prob. I was looking at the sequence and thought it looked a little funny. That and your comment about it ending with methionine. I was thinking, "what a farked up professor". ...just remember that it's always the mRNA that gets translated by the ribosomes into amino acids, never tRNA.

"And knowing is half the battle...G.I. Joe!"

 

[MrCodeDude]

Alright, so my book only gives the first three letters of each amino acid. Could you tell me if my spelling is wrong?

Methionine, Asinine, Alanine, Thrynine, Agrinine, Serine, Glynine, Serine, Hisinine, STOP

Thanks for all the help guys.
-- mrcodedude

 

[CStroman]

If you'd posted this a week from now, I'd be able to help you. This is the kind of stuff in the next chapter in my class.

 

[McPhreak]

<< Alright, so my book only gives the first three letters of each amino acid. Could you tell me if my spelling is wrong?

Methionine, Asinine, Alanine, Thrynine, Agrinine, Serine, Glynine, Serine, Hisinine, STOP

Thanks for all the help guys.
-- mrcodedude >>



Close, but no cigar.

Methionine, Asparagine (I think that's what you're trying to spell), Alanine, Threonine, Arginine, Serine, Glycine, Serine, Histidine