Amber codon

Amber Codon

The amber codon is a specific three-nucleotide sequence in DNA and RNA that signals the termination of protein synthesis. It is one of the three "stop" codons in the genetic code, the others being the ochre codon and the opal codon. The amber codon is represented by the nucleotide triplet "UAG".

History

The amber codon was first discovered in 1963 by scientists Richard J. Epstein and Charles Steinberg. They named it "amber" in honor of their colleague Harris Bernstein, whose last name means "amber" in German.

Function

The primary function of the amber codon is to signal the end of protein synthesis. When the ribosome, the molecular machine that builds proteins, encounters an amber codon, it recognizes this as a signal to stop adding amino acids to the growing protein chain. This ensures that the protein is of the correct length and sequence.

In some cases, organisms have evolved mechanisms to suppress the stop signal of the amber codon, allowing for the incorporation of non-standard amino acids into proteins. This is known as amber suppression.

Amber Suppression

Amber suppression is a phenomenon in molecular biology where the amber stop codon is overridden, or "suppressed". This can occur naturally in some organisms, or it can be engineered in the laboratory. Amber suppression allows for the incorporation of non-standard amino acids into proteins, which can be useful for studying protein structure and function.

See Also

• Genetic code
• Protein synthesis
• Stop codon
• Ochre codon
• Opal codon
• Amber suppression