WIKIMEDIA COMMONS, QUADELL
Once limited to cultured cells and unicellular organisms, researchers have now encoded a synthetic amino acid into the genome of Caenorhabditis elegans. The feat was achieved by designing a new transfer RNA (tRNA) molecule to carry the unnatural amino acid. When its corresponding 3-nucleotide codon appeared in the mRNA transcript, the synthetic amino acid was incorporated into the growing protein. Such rewriting of the genetic code has previously been achieved in E. coli, but this study demonstrated that a similar technique could work in multicellular organisms. Tagging the unnatural amino acid with a dye that glowed red under UV light allowed the team to confirm that the worms had indeed incorporated it into their proteins, ScienceNOW reports. The results were published last week in the Journal of the American Chemical Society.
Study author Jason Chin of the Medical Research Council's Laboratory of Molecular Biology told the BBC that the technique is "potentially transformational," allowing researchers to design proteins that they can precisely control, by for example, incorporating artificial amino acids that would allow researchers to turn proteins on or off using light, similar to current optogenetic techniques. Indeed, Chin and his colleagues are planning to investigate the possibility of activating or deactivating neurons with lasers, which would allow the detailed study of individual neuron function.