Imported:YPM/Kss1 num

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

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<modelParameter>Kss1_num = </modelParameter>930 to 20,795 molecules/cell

Source

• Quantitative western.

Trust

• Low

Additional Details

• Ghaemmaghami et al. (2003 PMID 14562106) measured 5480/cell by quantitative western of entire proteome.

• By FCS, the cytosolic Kss1 concentration was estimated to be 50 ± 6 nM in the absence of pheromone, and 55 ± 11 nM 2 hours after pheromone treatment. Slaughter et al. 2007 PMID 18077328
  • Assuming that the concentration of Kss1 does not change upon pheromone treatment, and the differences in measured values can be attributed to experimental error, the average concentration is 52.5 nM.
  • Given a cell volume of 29 fL (see Cell_volume), this corresponds to ~930 molecules per cell.

• Thomson et al. (in preparation) measured 20,795 molecules/cell by careful western blot.

Thomson et al. made careful measurements using purified Kss1 as a protein standard for their Western blots, and accounted for more sources of experimental error than Ghaemmaghami et al. However, there is no reason to suspect the 930 molecules per cell measured by Slaughter may be erroneous. Thus, all we can say is that the Kss1 abundance likely lies between 930 and 20,795 molecules/cell.