Question

When a sequence of deoxynucleotides is entered into a translation program (such as the ExPASy Translate tool at http://web.expasy.org/ translate/), six possible polypeptide sequences are given as results. Explain.

Short answer

When a sequence of deoxynucleotides is entered into a translation program, it can result in six possible polypeptides because mRNA can be read through six reading frames.

Step-by-step solution

Definition of Concept

In biology, a deoxynucleotide is a building block of DNA or deoxyribonucleic acid. A ribose sugar, phosphate, and an organic base make up a deoxynucleotide.

Six possible polypeptide sequences are given as results

The six possible polypeptide sequences are given as results when the deoxyribonucleotide sequence enters translation. It is due to its ability to read the sequence in six reading frames. There are three nucleotides in a codon, causing three reading frames in one direction. Another three reading frames in the opposite direction create a total of six reading frames that can result in six polypeptide sequences.