Double capacity of the UGA codon

2009/01/13 Kortabitarte Egiguren, Irati - Elhuyar Zientzia

• Biokimika
• Genetika

At the Euplotes crassus protozoo, researchers at the Nebraska University of the United States have discovered that the UGA codon can encode two amino acids. Normally, an elbow encodes a single amino acid. UGA codon can encode cysteine and selenocysteine amino acids.

The key is in a genetic sequence located at the end of the messenger RNA chain. This sequence creates a loop in the RNA chain and when reading the ribosome reads the modified UGA codon message. Without this they have seen that codon codes cysteine amino acid and with it selenocisteine amino acid.

In the future, the objective of the research team is to analyze how this sequence transforms the UGA code into concrete and see if this variability can occur in other organisms.

Image courtesy of: L. Clobutcher