Looking at stochasticity in nodes and in functions within gene regulartory (GR) networks. - Allyson Lister

How does the system behave when it is subjected to stochastic behaviour? - Allyson Lister

uses boolean modeling for this work - Allyson Lister

Boolean model: each protein can either be present or absent. The interaction network can be encoded with a set of boolean functions exhibiting steady states. - Gabriele Sales

Previous work: some nodes behave stochastically. - Gabriele Sales

With SIN (stochasticity in nodes), they had an example of stochastic cellular differentiation. You understand what the probabilities are in SIN by looking at a population of cells. - Allyson Lister

Example: stochasticity introduces cellular differentiation into a popolation. - Gabriele Sales

The SIN method overrepresents noise in the system. - Allyson Lister

This work employs a different approach: stochasticity in functions. The boolean function itself becomes noisy. - Gabriele Sales

Advantage of this approach: the noise can be selected depending on the biological function it applies to. - Gabriele Sales

Measure of robustness: probability of a steady state returning back to itself in the presence of internal pertubations (or faults). - Allyson Lister

Once you start introducing faults, the robustness is much lower the more faults you add for SIN, but the robustness is only marginally lower using SIF. - Allyson Lister

In SIN, 3 faults are sufficient to make all the states go into each other (results for the T-cell activation network). - Gabriele Sales

Nice to "see" you here @Gabriele - it's good to have more than one person commenting :) - Allyson Lister

@Allyson: I think this is getting addictive ;-) - Gabriele Sales

@Gabriele - yes it is - just make sure you control it, and not the other way around! ;) But seriously, if a person is going to take notes anyway, why not take them in a way that 1) other people can see them, and 2) is nicely indexed and searchable ... - Allyson Lister

Blog post: http://themindwobbles.wordpress.com/2009... - Allyson Lister