Molecular clustering digitizes signaling and increases fidelity

TL;DR

This paper demonstrates through a stochastic model that membrane molecule clusters convert signals into a digital form, reducing noise and increasing fidelity despite decreasing output states, with an optimal cluster size aligning with experiments.

Contribution

It introduces a stochastic model showing how cooperative clustering digitizes signals and enhances fidelity, revealing an optimal cluster size for signaling.

Findings

Cluster digitization reduces noise and increases fidelity.

Optimal cluster size matches experimental data.

Tradeoff between output states and noise impacts fidelity.

Abstract

Many membrane-bound molecules in cells form small clusters. It has been hypothesized that these clusters convert an analog extracellular signal into a digital intracellular signal and that this conversion increases signaling fidelity. However, the mechanism by which clusters digitize a signal and the subsequent effects on fidelity remain poorly understood. Here we demonstrate using a stochastic model of cooperative cluster formation that sufficient cooperation leads to digital signaling. We show that despite reducing the number of output states, which decreases fidelity, digitization also reduces noise in the system, which increases fidelity. The tradeoff between these effects leads to an optimal cluster size that agrees with experimental measurements.