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Progress toward an expanded eukaryotic genetic code.

Jason W Chin·T Ashton Cropp·Stephanie Chu·Eric Meggers·Peter G Schultz
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Abstract

Expanding the eukaryotic genetic code to include unnatural amino acids with novel properties would provide powerful tools for manipulating protein function in eukaryotic cells. Toward this goal, a general approach with potential for isolating aminoacyl-tRNA synthetases that incorporate unnatural amino acids with high fidelity into proteins in Saccharomyces cerevisiae is described. The method is based on activation of GAL4-responsive HIS3, URA3, or lacZ reporter genes by suppression of amber codons in GAL4. The optimization of GAL4 reporters is described, and the positive and negative selection of active Escherichia coli tyrosyl-tRNA synthetase (EcTyrRS)/tRNA(CUA) is demonstrated. Importantly, both selections can be performed on a single cell and with a range of stringencies. This method will facilitate the isolation of a range of aminoacyl-tRNA synthetase (aaRS)/tRNA(CUA) activities from large libraries of mutant synthetases.

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Amino AcidsAmino Acyl-tRNA SynthetasesEscherichia coliEukaryotic CellsGenes, ReporterGenetic CodeGenetic TechniquesProtein BiosynthesisProteinsRNA, Transfer, Amino AcylSaccharomyces cerevisiaeTranscription, GeneticJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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Jason W Chin, T Ashton Cropp, Stephanie Chu, Eric Meggers, Peter G Schultz. 2003. Progress toward an expanded eukaryotic genetic code.. https://doi.org/10.1016/s1074-5521(03)00123-6

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