Single Cell Model

The single-cell pathway model of our system is composed of 4 modules, which are responsible for routing the signal from the receptor to the GFP sythesis. The mathematical model is developed on a scheme favoring the temporal order of processes, based on the current understanding of the pheromone signalling pathway from [1][2][3] and on the feedback received from the experimentalists on the expected behaviour of the pathway, taking into consideration the aspects relevant to our project.

Model of the G - Protein cycle

The concentration of free G-beta-gamma dimer is crucial for the activation of the MAP kinase cascade which in turn activates the expression of the GFP. The promoter used for the receptor and the initial concentration of the ligand were thus crucial parameters for the activation of the G-Protein Cycle. A model of the G-Protein cycle by Yi et al [1] was used to analyze the effects of the different promoter strengths of the receptor and the effects of various initial concentrations on the activation of the G-Protein cycle.

Model of the Yeast Pheromone Response

A model of the yeast pheromone response by Kofahl and Klipp[2] was used to test the effects of knockout on the transcription factor Ste12.

Model of the Snifformyces Pathway

The model of the G-protein cycle lacked the description of the other aspects of the project. The model of the yeast pheromone response though was detailed still lacked the gene expression module. The model also suffered from a very high degree of complexity. Fitting parameters to the data generated from the lab to a model of such a high degree of complexity was not feasible. The initial models served as a good intuitive measure for experimental design.

For our project, we decided to opt for a new model of the