Rate of activation of alpha mating factor receptor

Value 1E-05 molecules/cell/sec
Organism Budding yeast Saccharomyces cerevisiae
Reference Yi TM, Kitano H, Simon MI. A quantitative characterization of the yeast heterotrimeric G protein cycle. Proc Natl Acad Sci U S A. 2003 Sep 16100(19):10764-9PubMed ID12960402
Method G protein activation rate was determined from FRET time course and dose–response data. Researchers constructed strains possessing genomic copies of the FRET pairs CFP-GPA1 (Ga) and STE18-YFP (G?), which replaced their cognate genes. They observed the dose-dependent loss of FRET on a-factor addition, which was quantitated by fluorometer. The kinetics and dose response of G protein activation were measured and compared with the pheromone responsiveness of two downstream events, cell-cycle arrest, and transcriptional activation of pheromone-inducible genes. Finally, researchers fit the data to a mathematical model that furnishes a detailed description of the yeast heterotrimeric G protein cycle (Fig. 1) and also enables quantitative explanations of the data.
Entered by Uri M
ID 104298