Imported:YPM/Ste7 num

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

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<modelParameter>Ste7_num = 960</modelParameter> molecules/cell

Source

• Quantitative western and FCS.

Trust

• Medium

Additional Details

• Ghaemmaghami et al. (2003 PMID 14562106) measured 672 molecules/cell by quantitative western of entire proteome.

• By FCS, the cytosolic Ste7 concentration was estimated to be 68 nM. Maeder et al. 2007 PMID 17952059
  • Given a cell volume of 29 fL (see Cell_volume), this corresponds to ~1,190 molecules per cell.

• By FCS, the cytosolic Ste7 concentration was estimated to be 44 ± 6 nM in both the absence and presence (2h post treatment) of pheromone. Slaughter et al. 2007 PMID 18077328
  • Given a cell volume of 29 fL (see Cell_volume), this corresponds to ~780 molecules per cell.

• Thomson et al. (in preparation) measured 920 molecules/cell by careful western blot.

Thomson et al. made careful measurements using purified Ste11 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 780-1,190 molecules per cell measured by Maeder and Slaughter may be erroneous. Thus, we average the abundance measured by Thomson, Maeder and Slaughter to get a Ste11 abundance of 960 molecules/cell.