What Should We Do About the Extra Nitrogenous Base in the RNA Sequence?

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The discussion revolves around the presence of an extra nitrogenous base in an RNA sequence derived from a DNA template. Participants note that the extra base may not code for anything significant, emphasizing the importance of identifying the start codon for translation. The consensus is that without a start codon, the sequence could be part of an untranslated region or a mid-region of translation. The correct start codon is identified as AUG, while UAC is recognized as a codon for tyrosine. Overall, the extra base is deemed negligible in terms of coding for amino acids.
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DNA Template: 3' AATGGCCAGTGGTTCGCAC 5'

Therefore: RNA: 5' UUACCGGUCACCAAGCGUG 3'

One problem, when using the genetic code we have an extra nitrogenous base. What to do?

Thanks :)
 
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The extra base(s) might not code for anything. You need to look for the start codon.
 
one problem i don't think there is a start codon there
 
In that case, the sequence you just listed could be part of an untranslated region in the DNA, or it could also be a translated region. It's just one segment of the DNA. Without any questions concerned with it, that's as much as you can know.
 
wow weird this assignment tells me to code it's amino acid sequence :( And there is no start codon.
 
But I do see a start codon. Look closer.
 
umm gug, but that's only one thing :( and then the next question would be like, adding a G to the eigth nucleotide of the DNA template, why is the mRNA (amino acids) sequence shorter. BUt instead it would be longer as GUG occurs earlier.
 
GUG is not a start codon. Your start codons in DNA start with TAC from the 3' to 5' end.
 
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ohh so it would start on the uac? we have to code for mRNA
 
  • #10
LadiesMan said:
ohh so it would start on the uac? we have to code for mRNA

Yes.

EDIT: whoops, Gannon is correct.
 
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  • #11
ok thanks.
 
  • #12
If there is no start codon present, you can usually assume that the sequence given is in the middle of a region being translated. It usually isn't a trick question about "there's no start codon, so no polypeptide is produced." There may be a stop codon present as well, which would terminate translation, but again, if there is none then the strand is a mid-region. As for the extra base, it is negligible because obviously no amino acid has a guanine-only tRNA complement.
 
  • #13
LadiesMan said:
ohh so it would start on the uac? we have to code for mRNA
No. The only start codon sequence is that for methionine (AUG). UAC is one of two sequences for tyrosine.
 
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