Please help me understand how tomatch up the codons. I know AT and GC pair up. B
ID: 3173 • Letter: P
Question
Please help me understand how tomatch up the codons. I know AT and GC pair up. But, where do I get U?For the double stranded DNA shown below, the bottom strand is thetemplate for transcription. If the START CODON is AUG and theSTOP CODON is UGA, how many amino acids are in the encoded proteinand what is the order of amino acids? Make a drawing to show how yougot your answer (how can I draw this out?).
3' - AGGTCCAGTCTTCGGCGGATGATCGGGCCAAACCCCGTAACTGGTCACCGGAATGCC -5' 5' - TCCAGGTCAGAAGCCGCCTACTAGCCCGGTTTGGGGCATTGACCAGTGGCCTTACGG -3' Please help me understand how tomatch up the codons. I know AT and GC pair up. But, where do I get U?
For the double stranded DNA shown below, the bottom strand is thetemplate for transcription. If the START CODON is AUG and theSTOP CODON is UGA, how many amino acids are in the encoded proteinand what is the order of amino acids? Make a drawing to show how yougot your answer (how can I draw this out?).
3' - AGGTCCAGTCTTCGGCGGATGATCGGGCCAAACCCCGTAACTGGTCACCGGAATGCC -5' 5' - TCCAGGTCAGAAGCCGCCTACTAGCCCGGTTTGGGGCATTGACCAGTGGCCTTACGG -3'
Explanation / Answer
Basicallyin DNA As pair with Ts, but in RNA there are no Ts and As insteadpairs with Us. So instead of AT base pairs you get AU basepairs.
So now wehave to look for the startcodon, AUG. Keep in mind though that RNA/DNA is read in the5' to 3' direction, so basically we have to read the top strandfrom right to left ( so we're looking for a GUA if you're readingfrom left to right.) We should also find the stop codon and keep in minddirectionality.
3' - AGGUCCAGUCUUCGGCGGAUGAUCGGGCCAAACCCCGUAACUGGUCACCGGAAUGCC- 5'
5' - TCCAGGTCAGAAGCCGCCTACTAGCCCGGTTTGGGGCATTGACCAGTGGCCTTACGG -3'
There are 33 nucleotides or 11 codons. The last codon is a stopcodon so there are only 10 amino acid residues in the final polypeptide. Their order is
Met-Pro-Gln-Thr-Gly-Leu-Val-Gly-Gly-Phe