Force-driven growth of intercellular junctions

TL;DR

This paper presents a physical model explaining how mechanical forces influence the growth of intercellular junctions, highlighting the role of catch bonds in mechanotransduction, based on thermodynamic principles.

Contribution

It introduces a thermodynamic model for junction growth under force, emphasizing the differential behavior of slip and catch bonds in cell adhesion.

Findings

Catch bonds exhibit mechanotransduction features under force.

Force affects the free energy landscape of cell junctions.

Passive thermodynamic response governs junction growth.

Abstract

Mechanical force regulates the formation and growth of cell-cell junctions. Cadherin is a prominent homotypic cell adhesion molecule that plays a crucial role in establishment of intercellular adhesion. It is known that the transmitted force through the cadherin-mediated junctions directly correlates with the growth and enlargement of the junctions. In this paper, we propose a physical model for the structural evolution of cell-cell junctions subjected to pulling tractions, using the Bell-Dembo-Bongard thermodynamic model. Cadherins have multiple adhesive states and may establish slip or catch bonds depending on the Ca 2+ concentration. We conducted a comparative study between the force-dependent behavior of clusters of slip and catch bonds. The results show that the clusters of catch bonds feature some hallmarks of cell mechanotransduction in response to the pulling traction. This is a passive thermodynamic response and is entirely controlled by the effect of mechanical work of the pulling force on the free energy landscape of the junction.