Gene Symbol: SSY1
Description: Ssy1p
Alias: RAA1, SHR10, Ssy1p
Species: Saccharomyces cerevisiae S288c

Top Publications

  1. Wu B, Ottow K, Poulsen P, Gaber R, Albers E, Kielland Brandt M. Competitive intra- and extracellular nutrient sensing by the transporter homologue Ssy1p. J Cell Biol. 2006;173:327-31 pubmed
    Recent studies of Saccharomyces cerevisiae revealed sensors that detect extracellular amino acids (Ssy1p) or glucose (Snf3p and Rgt2p) and are evolutionarily related to the transporters of these nutrients...
  2. Klasson H, Fink G, Ljungdahl P. Ssy1p and Ptr3p are plasma membrane components of a yeast system that senses extracellular amino acids. Mol Cell Biol. 1999;19:5405-16 pubmed
    ..b>Ssy1p is a unique member of the amino acid permease gene family, and Ptr3p is predicted to be a hydrophilic protein that ..
  3. Abdel Sater F, El Bakkoury M, Urrestarazu A, Vissers S, Andre B. Amino acid signaling in yeast: casein kinase I and the Ssy5 endoprotease are key determinants of endoproteolytic activation of the membrane-bound Stp1 transcription factor. Mol Cell Biol. 2004;24:9771-85 pubmed
    ..g., AGP1, encoding an amino acid permease. This sensing function requires the permease-like Ssy1 and associated Ptr3 and Ssy5 proteins, all essential to activation, by endoproteolytic processing, of the membrane-..
  4. Bernard F, Andre B. Ubiquitin and the SCF(Grr1) ubiquitin ligase complex are involved in the signalling pathway activated by external amino acids in Saccharomyces cerevisiae. FEBS Lett. 2001;496:81-5 pubmed
    In response to external amino acids, the permease-like sensor Ssy1 of Saccharomyces cerevisiae activates a pathway leading to transcriptional induction of several permease genes including AGP1 and PTR2...
  5. Tumusiime S, Zhang C, Overstreet M, Liu Z. Differential regulation of transcription factors Stp1 and Stp2 in the Ssy1-Ptr3-Ssy5 amino acid sensing pathway. J Biol Chem. 2011;286:4620-31 pubmed publisher
    ..Our results indicate that the functions of two seemingly redundant transcription factors can be separated by differential degradation and distinct cellular localization. ..
  6. Pfirrmann T, Heessen S, Omnus D, Andréasson C, Ljungdahl P. The prodomain of Ssy5 protease controls receptor-activated proteolysis of transcription factor Stp1. Mol Cell Biol. 2010;30:3299-309 pubmed publisher
    ..Our results define a regulatory mechanism that is novel for eukaryotic proteases functioning within cells. ..
  7. Omnus D, Pfirrmann T, Andréasson C, Ljungdahl P. A phosphodegron controls nutrient-induced proteasomal activation of the signaling protease Ssy5. Mol Biol Cell. 2011;22:2754-65 pubmed publisher
    Regulated proteolysis serves as a mechanism to control cellular processes. The SPS (Ssy1-Ptr3-Ssy5) sensor in yeast responds to extracellular amino acids by endoproteolytically activating transcription factors Stp1 and Stp2 (Stp1/2)...
  8. Bernard F, Andre B. Genetic analysis of the signalling pathway activated by external amino acids in Saccharomyces cerevisiae. Mol Microbiol. 2001;41:489-502 pubmed
    The permease-like amino acid sensor Ssy1p of Saccharomyces cerevisiae is required for transcriptional induction, in response to external amino acids, of several genes encoding peptide and amino acid permeases...
  9. Liu Z, Thornton J, Spirek M, Butow R. Activation of the SPS amino acid-sensing pathway in Saccharomyces cerevisiae correlates with the phosphorylation state of a sensor component, Ptr3. Mol Cell Biol. 2008;28:551-63 pubmed
    ..amino acids and activate expression of amino acid permeases through the SPS-sensing pathway, which consists of Ssy1, an amino acid sensor on the plasma membrane, and two downstream factors, Ptr3 and Ssy5...

More Information


  1. Iraqui I, Vissers S, Bernard F, De Craene J, Boles E, Urrestarazu A, et al. Amino acid signaling in Saccharomyces cerevisiae: a permease-like sensor of external amino acids and F-Box protein Grr1p are required for transcriptional induction of the AGP1 gene, which encodes a broad-specificity amino acid permease. Mol Cell Biol. 1999;19:989-1001 pubmed
    ..Compared to the 17 other proteins of this family, however, Ssy1p displays unusual structural features reminiscent of those distinguishing the Snf3p and Rgt2p glucose sensors from ..
  2. Kodama Y, Omura F, Takahashi K, Shirahige K, Ashikari T. Genome-wide expression analysis of genes affected by amino acid sensor Ssy1p in Saccharomyces cerevisiae. Curr Genet. 2002;41:63-72 pubmed
    Saccharomyces cerevisiae Ssy1p is a membrane protein which senses extracellular amino acids and controls the expression of certain amino acid permease genes...
  3. Liu Z, Sekito T, Epstein C, Butow R. RTG-dependent mitochondria to nucleus signaling is negatively regulated by the seven WD-repeat protein Lst8p. EMBO J. 2001;20:7209-19 pubmed two sites, one upstream of Rtg2p, affecting glutamate repression of RTG-dependent gene expression through Ssy1p, an AAP-like sensor of external amino acids, and the other between Rtg2p and Rtg1p-Rtg3p...
  4. Merhi A, Gérard N, Lauwers E, Prevost M, Andre B. Systematic mutational analysis of the intracellular regions of yeast Gap1 permease. PLoS ONE. 2011;6:e18457 pubmed publisher
    ..Interestingly, this direct vacuolar sorting seems to be independent of Gap1 ubiquitylation. This study illustrates the importance of multiple intracellular regions of Gap1 in its secretion, transport activity, and down-regulation. ..
  5. Scharff Poulsen P, Pedersen P. Saccharomyces cerevisiae-based platform for rapid production and evaluation of eukaryotic nutrient transporters and transceptors for biochemical studies and crystallography. PLoS ONE. 2013;8:e76851 pubmed publisher
    ..In conclusion, we developed a new effective S. cerevisiae expression system that may be used for production of high-quality eukaryotic membrane proteins for functional and structural analysis. ..
  6. Kralt A, Carretta M, Mari M, Reggiori F, Steen A, Poolman B, et al. Intrinsically disordered linker and plasma membrane-binding motif sort Ist2 and Ssy1 to junctions. Traffic. 2015;16:135-47 pubmed publisher
    ..In Ssy1, a protein that was not previously described to reside at membrane junctions, we recognized a domain organization ..
  7. Torbensen R, Møller H, Gresham D, Alizadeh S, Ochmann D, Boles E, et al. Amino acid transporter genes are essential for FLO11-dependent and FLO11-independent biofilm formation and invasive growth in Saccharomyces cerevisiae. PLoS ONE. 2012;7:e41272 pubmed publisher
    ..Invasive growth relied on known regulators of FLO11 and the Ssy1-Ptr3-Ssy5 complex that controls DIP5 and GNP1, suggesting that Dip5 and Gnp1 operates downstream of the Ssy1-Ptr3-..
  8. Poulsen P, Gaber R, Kielland Brandt M. Hyper- and hyporesponsive mutant forms of the Saccharomyces cerevisiae Ssy1 amino acid sensor. Mol Membr Biol. 2008;25:164-76 pubmed publisher
    The Saccharomyces cerevisiae integral membrane protein Ssy1p functions with Ssy5p and Ptr3p to sense extracellular amino acids...
  9. Brown K, Landry C, Hartl D, Cavalieri D. Cascading transcriptional effects of a naturally occurring frameshift mutation in Saccharomyces cerevisiae. Mol Ecol. 2008;17:2985-97 pubmed publisher
    ..mutation is a frameshift mutation in a mononucleotide run of eight consecutive T's in the coding region of the gene SSY1, which encodes a key component of a plasma-membrane sensor of extracellular amino acids...
  10. Forsberg H, Hammar M, Andreasson C, Moliner A, Ljungdahl P. Suppressors of ssy1 and ptr3 null mutations define novel amino acid sensor-independent genes in Saccharomyces cerevisiae. Genetics. 2001;158:973-88 pubmed
    b>Ssy1p and Ptr3p are components of the yeast plasma membrane SPS amino acid sensor...
  11. Tsang F, James C, Kato M, Myers V, Ilyas I, Tsang M, et al. Reduced Ssy1-Ptr3-Ssy5 (SPS) signaling extends replicative life span by enhancing NAD+ homeostasis in Saccharomyces cerevisiae. J Biol Chem. 2015;290:12753-64 pubmed publisher
    ..Here we identify the Ssy1-Ptr3-Ssy5 (SPS) amino acid sensing pathway as a novel longevity factor...
  12. Abdel Sater F, Iraqui I, Urrestarazu A, Andre B. The external amino acid signaling pathway promotes activation of Stp1 and Uga35/Dal81 transcription factors for induction of the AGP1 gene in Saccharomyces cerevisiae. Genetics. 2004;166:1727-39 pubmed
    ..The signaling pathway responsible for this induction involves Ssy1, a permease-like sensor of external amino acids, and culminates with proteolytic cleavage and translocation to the ..
  13. Nigavekar S, Cannon J. Characterization of genes that are synthetically lethal with ade3 or leu2 in Saccharomyces cerevisiae. Yeast. 2002;19:115-22 pubmed
    ..Using a LEU2-ADE3 plasmid, plasmid-dependent mutations were found in the SHM2, PTR3, BAP2 and SSY1 genes. Double shm2 ade3 mutants are non-viable because the two pathways for tetrahydrofolate synthesis are blocked...
  14. Omnus D, Ljungdahl P. Rts1-protein phosphatase 2A antagonizes Ptr3-mediated activation of the signaling protease Ssy5 by casein kinase I. Mol Biol Cell. 2013;24:1480-92 pubmed publisher
    ..In response to extracellular amino acids, the yeast Ssy1-Ptr3-Ssy5 sensor triggers the endoproteolytic processing of transcription factors Stp1 and Stp2 to induce amino ..