ARUP; ISBN: 978-0-9562121-5-3 - CMBBE 2012 - Cardiff University

Figure 4: Typical representation of sorted flock at t = 18 : 03h. Note the detached cell.
5 CONCLUSION AND OUTLOOK
The individual-cell based model could be specialized for the case of budding yeast. We were able
to significantly substantiate the hypothesis that the FLO1 gene is recognized simply by the mechanical
parameter of adhesion strength by other cells also expressing FLO1. This is an interesting
case of a “green beard gene” showing how evolution lead to cooperation in yeast.
When measurements on σ++ and σ−− become available, the model can be further validated. It will
be interesting to see, whether the model’s predictions about sorting of mixed colonies of different
adhesion strengths can be validated (experiments are under way).
ACKNOWLEDGEMENT
We acknowledge funding by the SEED project financing.
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