Robustness of the Drosophila segment polarity network to transient perturbations

TL;DR

This study investigates how the Drosophila segment polarity network maintains its pattern despite transient environmental perturbations, highlighting critical nodes and the system's sensitivity to specific changes.

Contribution

It introduces a Boolean model to analyze the network's resilience to transient perturbations and identifies key nodes affecting robustness.

Findings

The network is more sensitive to activation of normally inactive nodes.

Localized perturbations are more damaging than global ones.

The system can recover from transient heat shock conditions.

Abstract

Continuous and Boolean models for the Drosophila segment polarity network have shown that the system is able to maintain the wild-type pattern when subjected to sustained changes in the interaction parameters and initial conditions. Embryo development is likely to occur under fluctuating environmental conditions. We use a well-established Boolean model to explore the ability of the segment polarity network to resist transient changes. We identify paths along which alternate unviable states are reached, and hence critical nodes whose state changes lead the system away from the wild-type state. We find that the system appears to be more sensitive to changes that involve activation of normally inactive nodes. Through a simulation of the heat shock response, we show how a localized perturbation in one parasegment is more deleterious than a global perturbation affecting all parasegments. We identify the sequence of events involved in the recovery of the system from a global transient heat shock condition. Finally we discuss these results in terms of the robustness of the system response.