<molecular biology> The coding unit of DNA that specifies the function of the corresponding messenger RNA.

A triplet of bases recognised by anticodons on transfer RNA and hence specifying an amino acid to be incorporated into a protein sequence. The code is degenerate, i.e. Each amino acid has more than one codon. The stop codon determines the end of a polypeptide.

This entry appears with permission from the Dictionary of Cell and Molecular Biology

(11 Mar 2008)