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About Far1

  • Far1 contains a putative MAPK-binding sequence at residues 72-82. Metodiev et al. 2002 PMID 12029138
  • Far1 expression is upregulated in response to pheromone treatment. Chang & Herskowitz. 1990 PMID 2147873
  • Far1 degradation may be regulated by phosphorylation, perhaps by the CLN proteins. McKinney et al. 1993 PMID 8491380
    • Phosphorylated Far1 appears just before the rapid decline in Far1 protein abundance at the cell cycle Start.
  • Far1 is expressed in a cell cycle dependent manner. Oehlen et al. 1996 PMID 8649392
  • Far1 contains a bipartite nuclear localization sequence at residues 11-30,38-48. These residues are necessary and sufficient for nuclear localization. Blondel et al. 1999 PMID 10485850
  • Far1 is exported from the nucleus by Msn5 (also known as Ste21, often referred to as Msn5/Ste21). Blondel et al. 1999 PMID 10485850
    • When Msn5 is overexpressed, export of Far1 from the nucleus does not require a functioning mating pathway, although pheromone treatment does increase cyctoplasmic localization of Far1.
    • Pheromone-treatment doesn't noticeably affect the two-hybrid interaction between Msn5 and Far1, suggesting that pheromone may not regulate the interaction between Far1 and Msn5.
    • Cytoplasmic localization of Far1 caused by Msn5 overexpression does not activate the mating pathway.
    • The ability of Far1 to bind Msn5 is separable from its ability to bind Cdc28.
  • Cytoplasmic Far1 appears to be involved in determining cell polarity, and nuclear Far1 is important for cell cycle arrest. Blondel et al. 1999 PMID 10485850
  • WT Far1 (nuclear) has a half-life of about 20 minutes (averaged over the cell cycle). Blondel et al. 2000 PMID 11080155
    • Far1 missing the N-terminal NLS (cytoplasmic) has a half-life of 45-55 minutes.
    • Far1(S87A) (nuclear), which cannot be phosphorylated by Cdc28, has a half-life of 60 minutes.
    • Far1(S87A) missing the N-terminal NLS (cytoplasmic) has a half-life of 100 minutes, suggesting the mechanism that stabilizes cytoplasmic Far1 and the mechanism that stabilizes non-phosphorylatable Far1 may be different.
  • Both nuclear and cytoplasmic Far1 can be phosphorylated by Cdc28-Cln. Blondel et al. 2000 PMID 11080155
    • Cln1 and Cln2 are localized to both the nucleus and cytoplasm.
  • Evidence suggests that Far1 is efficiently ubiquitinated and degraded in the nucleus. Blondel et al. 2000 PMID 11080155
    • Although Cdc53, Skp1, Cdc43 and Hrt1 are localized to both the nucleus and cytoplasm, Cdc4 is exclusively localized to the nucleus.
    • Localization of Cdc4 to the cytoplasm destabilizes cytoplasmic Far1.


Far1/MAPK interactions
Ste12 mediated protein synthesis
Non-specific dephosphorylation
Protein dilution/synthesis due to cell growth

Species Representation

Molecule Type

Far1(MAPK_site, S87~none~PO4, T306~none~PO4)

Model Seed

Far1(MAPK_site, S87~none, T306~none) Far1_tot_conc

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