Heat-inducible degron: a method for constructing temperature-sensitive mutants.

R J Dohmen; P Wu; A Varshavsky

doi:10.1126/science.8122109

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PubMed · 8122109

Heat-inducible degron: a method for constructing temperature-sensitive mutants.

R J Dohmen·P Wu·A Varshavsky

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Abstract

A temperature-sensitive (ts) mutant retains the function of a gene at a low (permissive) temperature but not at a high (nonpermissive) temperature. Arg-DHFR, a dihydrofolate reductase bearing an amino-terminal (N-terminal) arginine, is long-lived in the yeast Saccharomyces cerevisiae, even though arginine is a destabilizing residue in the N-end rule of protein degradation. A ts derivative of Arg-DHFR was identified that is long-lived at 23 degrees C but rapidly degraded by the N-end rule pathway at 37 degrees C. Fusions of ts Arg-DHFR to either Ura3 or Cdc28 of S. cerevisiae confer ts phenotypes specific for these gene products. Thus, Arg-DHFRts is a heat-inducible degradation signal that can be used to produce ts mutants without a search for ts mutations.

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CDC28 Protein Kinase, S cerevisiae Fungal Proteins Half-Life Hot Temperature Mutagenesis Phenotype Recombinant Fusion Proteins Saccharomyces cerevisiae Temperature Tetrahydrofolate Dehydrogenase Ubiquitins Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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R J Dohmen, P Wu, A Varshavsky. 1994-03-04. Heat-inducible degron: a method for constructing temperature-sensitive mutants.. https://doi.org/10.1126/science.8122109

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