Polynomial algebra reveals diverging roles of the unfolded protein response in endothelial cells during ischemia-reperfusion injury

The unfolded protein response (UPR) - the endoplasmic reticulum stress response - is found in various pathologies including ischemia-reperfusion injury (IRI). However, its role during IRI is still unclear. Here, by combining two different bioinformatical methods - a method based on ordinary differential equations (Time Series Network Inference) and an algebraic method (probabilistic polynomial dynamical systems) - we identified the IRE1 alpha-XBP1 and the ATF6 pathways as the main UPR effectors involved in cell's adaptation to IRI. We validated these findings experimentally by assessing the impact of their knock-out and knock-down on cell survival during IRI. (C) 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.