Math Biology Seminar: Alexandra Jilkine
Topic
Modeling the Dynamics of Cdc42 Oscillation in Fission Yeast
Speakers
Details
We present a mathematical model of the core mechanism responsible for the regulation of polarized growth dynamics by the small GTPase Cdc42. The model is based on the competition of growth zones of Cdc42 localized at the cell tips for a common substrate (inactive Cdc42) that diffuses in the cytosol. We consider several potential ways of implementing negative feedback between Cd42 and its GEF in this model that would be consistent with the observed oscillations of Cdc42 in fission yeast. We analyze the bifurcations in this model as the cell length increases, and total amount of Cdc42 and GEF increase. Symmetric antiphase oscillations at two tips emerge via saddle-homoclinic bifurcations or Hopf bifurcations. We find that a stable oscillation and a stable steady state can coexist, which is consistent with the experimental finding that only 50% of bipolar cells oscillate. Our model suggests that negative feedback is more likely to be acting through inhibition of GEF association rather than upregulation of GEF dissociation.
Additional Information
Location: ESB 4127 (PIMS videoconference room)
Wed 14 Mar 2018, 3:15pm-4:15pm
Alexandra Jilkine, Notre Dame University
Alexandra Jilkine, Notre Dame University
This is a Past Event
Event Type
Scientific, Seminar
Date
March 14, 2018
Time
-
Location