University of California Santa Barbara

Title:

Spatial Stochastic Simulation of Polarization in Yeast Mating

Abstract:

In microscopic systems formed by living cells, the small numbers of some reactant molecules can result in dynamical behavior that is discrete and stochastic rather than continuous and deterministic.  Spatio-temporal gradients and patterns play an important role in many of these systems.  In this lecture we report on recent progress in the development of computational methods and software for spatial stochastic simulation.  Then we describe a spatial stochastic model of polarisome formation in mating yeast.  The new model is built on simple mechanistic components, but is able to achieve a highly polarized phenotype with a relatively shallow input gradient, and to track movement in the gradient.  The spatial stochastic simulations are able to reproduce experimental observations to an extent that is not possible with deterministic simulation.

Bio:

Dr. Linda Petzold is currently Professor in the Department of Computer Science (Chair 2003-2007) and the Department of Mechanical Engineering, and Director of the Computational Science and Engineering Program at the University of California Santa Barbara.  She received her Ph.D. in Computer Science in 1978 from the University of Illinois.  From 1978-1985 she was a member of the Applied Mathematics Group at Sandia National Laboratories in Livermore, California, from 1985-1991 she was Group Leader of the Numerical Mathematics Group at Lawrence Livermore National Laboratory, and from 1991-1997 she was Professor in the Department of Computer Science at the University of Minnesota.  Dr. Petzold is a member of the US National Academy of Engineering.  She was recently named the Faculty Research Lecturer for 2011, the highest honor that UCSB bestows to its faculty.  She is a Fellow of the ASME,SIAM and AAAS. She was awarded the Wilkinson Prize for Numerical Software in 1991, the Dahlquist Prize in 1999, and the AWM/SIAM Sonia Kovalevski Prize in 2003.  She served as SIAM (Society for Industrial and Applied Mathematics) Vice President at Large from 2000-2001, as SIAM Vice President for Publications from 1993-1998, and as Editor in Chief of the SIAM Journal on Scientific Computing from 1989-1993.