Answer:
AAA-GAA-TAA-CAA
Explanation:
To answer this question we need to look at the genetic code, which tells us the possible codons in the mRNA that code for the different amino acids.
- The amino acid Phe is determined by the codon UUU or UUC in the mRNA.
- Leu is determined by CUU, CUC, CUA and CUG in the mRNA.
- Ile is coded by AUU, AUA and AUC.
- Val is coded by GUU, GUA, GUC and GUG.
The DNA molecule has two strands: the coding strand and the template strand. The coding strand is the strand that has the sequence of nucleotides that will be present in the mRNA, that will be translated into proteins.
The template strand is the DNA strand that the RNA polymerase copies to synthesize a complementary mRNA. Because the question is asking for a possible sequence of nucleotides in the template strand, we need to write down the complementary codons to those found in the mRNA.
Using the first possible codons for each amino acid, we have the following DNA sequence:
- Phe is coded by UUU, so the template strand will have the complementary AAA.
- Leu is determined by CUU, so the template strand will have the complementary GAA.
- Ile is coded by AUU, so the template strand will be TAA.
- Val is coded by GUU, so the template strand will be the complementary CAA.
Therefore, a possible sequence of nucleotides in the template strand of DNA that would code for the polypeptide sequence phe-leu-ile-val would be AAA-GAA-TAA-CAA
