Constitutive and hyperresponsive signaling by mutant forms of Saccharomyces cerevisiae amino acid sensor Ssy1.
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ABSTRACT:
SUBMITTER: Gaber RF
PROVIDER: S-EPMC219377 | biostudies-literature | 2003 Oct
REPOSITORIES: biostudies-literature
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Constitutive and hyperresponsive signaling by mutant forms of Saccharomyces cerevisiae amino acid sensor Ssy1.
Gaber Richard F RF Ottow Kim K Andersen Helge A HA Kielland-Brandt Morten C MC
Eukaryotic cell 20031001 5
Sensing of extracellular amino acids results in transcriptional induction of amino acid permease genes in yeast. Ssy1, a membrane protein resembling amino acid permeases, is required for signaling but is apparently unable to transport amino acids and is thus believed to be a sensor. By using a novel genetic screen in which potassium uptake was made dependent on amino acid signaling, we obtained gain-of-function mutations in SSY1. Some alleles confer inducer-independent signaling; others increase ...[more]
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