Question

Following is the sequence of amino acids coded by an mRNA. Predict the nucleotide sequence in the RNA: Met-Phe-Phe-Phe-Phe-Phe-Phe

Answer 1

Part 1: Introduction

• The DNA and RNA carry genetic information in the form of codons called genetic code.
• The codons are triplets that comprise the sequence of three nucleotides.
• Each codon codes for a specific amino acid.
• But an amino acid can be coded by more than one codon.
• Thus if we are given a sequence of amino acid, there can be multiple codons that would have coded these amino acids.

Part 2: Sequence of m- RNA
Met-Phe-Phe-Phe-Phe-Phe-Phe is the given amino acid sequence. Methionine is encoded by only one codon - AUG. Phenylalanine is encoded by two codons - UUU, UUC There are various combinations possible, few of them are listed below:

• AUG-UUU-UUU-UUU-UUU-UUU-UUU
• AUG-UUC-UUC-UUC-UUC-UUC-UUC