Direction dependent mechanical unfolding and Green Fluorescent Protein as a force sensor

TL;DR

This paper uses an Ising-like model to study how Green Fluorescent Protein unfolds under different pulling directions, revealing pathways and forces consistent with experiments, and proposes a force sensor based on this direction dependence.

Contribution

It introduces a direction-dependent model of protein unfolding and proposes a novel force sensor utilizing GFP's luminescence response to applied force.

Findings

Reproduces experimental unfolding pathways and forces

Identifies the correct order of magnitude for unfolding forces

Proposes a GFP-based force sensor leveraging direction-dependent luminescence

Abstract

An Ising--like model of proteins is used to investigate the mechanical unfolding of the Green Fluorescent Protein along different directions. When the protein is pulled from its ends, we recover the major and minor unfolding pathways observed in experiments. Upon varying the pulling direction, we find the correct order of magnitude and ranking of the unfolding forces. Exploiting the direction dependence of the unfolding force at equilibrium, we propose a force sensor whose luminescence depends on the applied force.