Simulation Model of a Possible Trigger for Reversible Switching of the Stress Regime in Plants

Abstract

A simulation model of a trigger mechanism that reversibly switches a plant to the stress regime in response to adverse environmental effects is suggested and investigated. This mechanism is activated by an elevated level of specific cell metabolites and, by inhibiting the customary synthetic processes, actuates the formation of systems that counteract the deregulation of plant metabolism. The operation of the postulated mechanism corresponds better to the known patterns of plant transition between the normal and stress states than the operation of common triggers. The model describes the reversibility of stress response and its relation to the intensity of environmental effects. The model also suggests that the stress response in plants is aimed at stabilizing the cell level of “dangerous” stress metabolites under adverse environmental conditions and providing for the termination of plant stress after cessation of the action of a stress factor. The possible actual prototypes of the model variables are discussed and used to explain several phenomena observed in plants under stress conditions, in particular, the changes in the system of prooxidant–antioxidant equilibrium.