Imported:YPM/Ste7

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Category:Species - Yeast Pheromone Response Model Back to main model page



About Ste7

  • Ste7 is hyperphosphorylated in response to pheromone. This requires a functioning Ste7, so presumably it is phosphorylated by Fus3/Kss1. Zhou et al. 1993 PMID 8455599
  • Ste7 is phosphorylated at threonine 363 by Ste11. Neiman and Herskowitz 1994 PMID 8159759
  • Ste7 activation requires phosphorylation at serine 359 and threonine 363. Zheng and Guan 1994 PMID 8131746
  • Prior to pheromone stimulation, Ste7-GFP (overexpressed from the Gal promoter) is dispersed evenly throughout the cytoplasm. 2 hours after pheromone treatment, Ste7-GFP is localized to the shmoo tip. van Drogen et al. 2001 PMID 11781566
  • Ste7 mutant S368P is constitutively active in the absence of pheromone, but its activity is increased upon treatment with pheromone. Ste7(S368P) activity still depends on Ste11. The mutant may be a better substrate for Ste11 or a worse substrate for phosphatase. Yashar et al. 1995 PMID 8524219
  • Ste7 is phosphorylated by Fus3 in vitro at S105, T116, S130, T137, T149, S167, and S471. Meleri et al. 2004 PMID 15456892
  • Ste7(S359E T363E) causes consitutive activation of the filamentous growth response, but not the pheromone response. Meleri et al. 2004 PMID 15456892
    • In vitro Ste7(S359E T363E) is able to phosphorylate both Fus3 and Kss1.
    • In vivo, Kss1 is phosphorylated but this constitutive Ste7 mutant, but Fus3 is not. This effect is not changed when the Ste7's 7 feedback phosphorylation sites are mutated to glutamates or alanines (Ste7-E7 and Ste7-A7).
  • Fluorescently-tagged Ste7, expressed at wild-type levels, is largely cytoplasmic in the absence and presence of pheromone. Maeder et al. 2007 PMID 17952059

Reactions

Ste5/MAPK cascade interactions
MAPK phosphorylation cascade
Ste7/MAPK interactions
Ste7 synthesis/degradation
Non-specific dephosphorylation
Protein dilution/synthesis due to cell growth

Species Representation

Molecule Type

<modelMoleculeType>Ste7(Ste5_site, MAPK_site, S359_T363~none~pS~pSpT)</modelMoleculeType>

Model Seed

<modelSeedSpecies>Ste7(Ste5_site, MAPK_site, S359_T363~none) Ste7_tot_conc</modelSeedSpecies>