Properties of Cooperatively Induced Phases in Sensing Models

TL;DR

This paper investigates how cooperative interactions among sensors on a cell surface can enhance and alter the cell's ability to detect external chemical gradients, revealing emergent sensing states and nonlinear responses.

Contribution

It introduces a model of sensor cooperation on a cell surface, demonstrating how weak and strong interactions lead to linear amplification and nonlinear collective responses.

Findings

Weak interactions linearly amplify gradient detection.

Strong interactions produce a nonlinear '1/2-state' with active and inactive sensor domains.

Different sensing behaviors emerge in strongly interacting sensor networks.

Abstract

A large number of eukaryotic cells are able to directly detect external chemical gradients with great accuracy and the ultimate limit to their sensitivity has been a topic of debate for many years. Previous work has been done to understand many aspects of this process but little attention has been paid to the possibility of emergent sensing states. Here we examine how cooperation between sensors existing in a two dimensional network, as they do on the cell's surface, can both enhance and fundamentally alter the response of the cell to a spatially varying signal. We show that weakly interacting sensors linearly amplify the sensors response to an external gradient while a network of strongly interacting sensors form a collective non-linear response with two separate domains of active and inactive sensors forming what have called a "1/2-state" . In our analysis we examine the cell's ability to sense the direction of a signal and pay special attention to the substantially different behavior realized in the strongly interacting regime.