Amber suppressor

Amber Suppressor

An amber suppressor is a type of mutation that alters the genetic code of an organism, allowing it to continue synthesizing proteins even in the presence of an amber stop codon. This mutation is named after the amber stop codon, which is one of the three stop codons in the genetic code that signals the end of protein synthesis.

Mechanism

The amber suppressor mutation occurs in a transfer RNA (tRNA) gene, causing the tRNA to recognize the amber stop codon (UAG) as a signal for incorporating an amino acid into the growing polypeptide chain, instead of stopping protein synthesis. This allows the protein synthesis to continue past the point where it would normally stop.

Applications

Amber suppressors have been used in genetic engineering to incorporate non-standard amino acids into proteins. This is done by engineering the tRNA to recognize the amber stop codon and incorporate the non-standard amino acid at that point in the protein. This technique has been used to study protein structure and function, and to create proteins with novel properties.

See also

• Nonsense mutation
• Stop codon
• Genetic code
• Transfer RNA