Question

What amino acid sequence is coded for by the following mRNA base sequence?

$\left(5^{\text{'}}\right)\mathbf{\text{CUA-GAC-CGU-UCC-AAG-UGA}}\left(3^{\text{'}}\right)$

Short answer

The amino acid sequence for the given DNA sequence is,

$5^{\text{'}}\text{-Leu-Asp-Arg-Ser-Lys-}{3}^{\text{'}}$

Step-by-step solution

Introduction

Messenger RNA (mRNA) is responsible for directing the creation of hundreds of different peptides and proteins that organisms require. Protein biosynthesis is carried out on ribosomes, which are tiny granular particles made up 60% of ribosomal RNA and 40% protein that are found in the cytoplasm of a cell.

The unique sequence of mRNA creates a message that specifies the amino acid residue sequences that must be linked, referred to as "codon." Each "word," or codon, is made up of three ribonucleotides that are unique to a certain amino acid. In a process known as translation, the message encoded in mRNA is read by transfer RNA (tRNA).

Codon assignment of base triplet

The direction of writing the bounded amino acid sequence is always the same $5^{\text{'}}\to 3^{\text{'}}$. tRNA, which possesses the corresponding anticodon base, reads the codon sequence on mRNA.

The tabulation is,

DNA coding strand

The DNA sequence in the given is (sense strand),

$\left(5^{\text{'}}\right)\text{CUA-GAC-CGU-UCC-AAG-UGA}\left(3^{\text{'}}\right)$

The original DNA strand is (the sense strand),

$\left(5^{\text{'}}\right)\text{CUA-GAC-CGU-UCC-AAG-UGA}\left(3^{\text{'}}\right)$

Converting the DNA sense strand into the antisense strand.

On replacing G by C, C by G, A by U and T by A to find the mRNA.

The UGA codon does not code for any amino acid. So it is called a stop codon.

Thus, the amino acid sequence is$5^{\text{'}}\text{-Leu-Asp-Arg-Ser-Lys-}{3}^{\text{'}}$