A bistable mechanism for directional sensing

Abstract

We present a generic mechanism for directional sensing in\neukaryotic cells that is based on bistable dynamics. As the key feature of this\nmodeling approach, the velocity of trigger waves in the bistable sensing system\nchanges its sign across cells that are exposed to an external chemoattractant\ngradient. This is achieved by combining a two-component activator/inhibitor\nsystem with a bistable switch that induces an identical symmetry breaking\nfor arbitrary gradient input signals. A simple kinetic example is designed to\nillustrate the dynamics of a bistable directional sensing mechanism in numerical\nsimulations.