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About Sst2

  • N terminal 300 residues show homology to segments in two mammalian GTPase-activating proteins (GAPs). The segments have been shown to be necessary and sufficient for GAP activity. Dohlman et al. 1996 PMID 8756677
  • Sst2-Myc is found throughout the cytosol, but it not found in the vacuole or nucleus (determined by confocal microscopy). Dohlman et al. 1996 PMID 8756677
  • C terminal RGS(Regulator of G protein Signaling)-like domain is also necesary for Sst2 activity in vivo. Dohlman et al. 1996 PMID 8756677
  • Sst2 is largely membrane associated. Dohlman et al. 1996 PMID 8756677
  • Sst2 stands for SuperSensiTivity to pheromone. Apanovitch et al. 1998 PMID 9537998
  • Sst2 acts as a GAP for Gpa1 by stabilizing the transition state of the GTP hydrolysis reaction. Apanovitch et al. PMID 9537998
  • Sst2 association with membrane appears to be mainly electrostatic. Dohlman et al. 1996 PMID 8756677
  • Sst2 is phosphorylated at S539 in response to pheromone. Garrison et al. 1999 PMID 10593933
  • Quantitative Western blots were used to show that there are ~2000 Sst2 molecules per cell prior to pheromone stimulation, and a peak of ~5000 Sst2 molecules per cell about 1 hour after pheromone stimulation. Hao et al. 2003 PMID 12968019
  • Sst2 deletion results in 100-fold increase in pheromone sensitivity, but no increase in maximum gene expression. Hao et al. 2003 PMID 12968019


RGS(Sst2)/Galpha(Gpa1)/Receptor(Ste2) interactions
G protein nucleotide hydrolysis/exchange
Sst2 synthesis/degradation
Ste12 mediated protein synthesis
Non-specific dephosphorylation
Protein dilution/synthesis due to cell growth

Species Representation

Molecule Type

Sst2(Ste2_site, MAPK_site, S539~none~PO4)

Model Seed

Sst2(Ste2_site, MAPK_site, S539~none) Sst2_tot_conc

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