amino acid codon a basic question- plz help - (May/23/2007 )

Hi

we all know that amino acids have more than one codons. I am checking the DNA sequence of a protein. In the sequencing result where I was expecting TCC I found TCT. But TCT will bring Serine same as TCC. Another one is in place of GCG (Ala) I found GCT(Ala). Though the nucleotide bases found different, but they will incorporate the same amino acid.

I am going to express this protein in HeLa by transfecting its corresponding DNA(tagged with a Expression vector). But if this DNA(cDNA) has those change in base sequence as I mentioned before, will the same protein will be produced in cells?

can anybody help me here?

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i think as long as the amino acid sequence wasn't changed, it will be the same. sorry, i'm not a 'protein' person. but logically, it should still work as long as there is not stop codon in the middle of your sequence.

good luck!

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It should still work. I have expressed some proteins with that kind of mutations before, they are alright.

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these are synonymous codons which encode for the same amino acid, so i think the same protein is supposed to be produced (degeneracy)

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the question is, why there are other codons expected? what is the reference? anyway, these silent mutations may not disturb functional expression of your protein if there are no mutations which lead to amino acid exchange;

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if the aminoacid isn't changed there shouldn't be a difference, but sometimes proteins (e.g. prokaryotic, mitochondrial) have a slightly different code.

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some organisms prefer a particular codon over another for the same amino acid. So you could have got the sequence from net derived from a species and are comparing it to the one derived from a different species, although they have the same protein sequence.

Some times you could find that 2 labs have submitted sequences which have the same protien sequence but different amino acid sequence for the same species.

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Thx to All.

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Degeneracy of the GENETIC CODE helps in the codon optimization of the gene sequences for better expression.
As long as the protein sequence corresponding to the codons sequence, no problem occurs.
At the same time check the secondary structure of mRNA.some times other codons for the same amino acid needs to be incorporated to overcome the strong mRNA folds, which pauses translation of protein

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Degeneracy of the GENETIC CODE helps in the codon optimization of the gene sequences for better expression.
As long as the protein sequence corresponding to the codons sequence, no problem occurs.
At the same time check the secondary structure of mRNA.some times other codons for the same amino acid needs to be incorporated to overcome the strong mRNA folds, which pauses translation of protein

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