Force transmission at cell-cell and cell-matrix adhesions

Cells constantly experience mechanical forces from their environment. These forces are detected by adhesion receptors on the cell surface. Once detected, the forces cause changes in the actin cytoskeleton and expansion of adhesion complexes. This process helps the cell resist and adapt to mechanical stress. Prior research has shown that integrins and cadherins are key receptors involved in force sensing. However, the exact mechanisms of how these receptors transmit forces into the cell remain unclear. This gap motivated researchers to explore how different adhesion complexes respond to mechanical stimuli. That uncertainty drove the need to compare integrin and cadherin signaling pathways.

This review aims to clarify how integrins and cadherins detect and transmit mechanical forces within cells. The study focuses on the proteins recruited by each adhesion complex to manage force. It also examines the signaling pathways that regulate cell contractility in response to force. The goal is to highlight how these two types of adhesions differ and interact. The authors seek to identify shared and unique mechanisms of force transmission. They also aim to explain how cells adjust their internal tension based on external forces. This work addresses a gap in understanding how mechanical signals are processed at the cell surface. The study provides a framework for future investigations into mechanosensing.

The authors conducted a comprehensive literature review on integrin and cadherin force transmission. They analyzed recent studies on adhesion proteins and signaling pathways. The review includes comparisons of how each adhesion complex recruits force-bearing proteins. The authors examined data on cytoskeletal rearrangements triggered by mechanical forces. They also assessed the role of signal transduction in modulating cell contractility. The study integrates findings from multiple disciplines including cell biology and biophysics. The authors synthesized evidence on the similarities and differences between adhesion types. They focused on how cells adapt their internal forces to maintain stability.

The review highlights that integrins and cadherins both detect mechanical forces but recruit distinct sets of proteins. Integrins primarily engage talin and vinculin to bear force. Cadherins rely on α-catenin and β-catenin for force transmission. Both adhesion types activate Rho GTPases to regulate actin dynamics. Integrins stimulate FAK and Src kinases to initiate signaling cascades. Cadherins activate the Hippo pathway to control cell contractility. The study reveals that integrin-mediated adhesions are more dynamic in response to force. Cadherin-based adhesions show longer-term stability and signaling. The findings suggest that both adhesion types use overlapping but distinct mechanisms to manage force.

The authors conclude that integrins and cadherins use different but complementary mechanisms to transmit forces. Integrins are more involved in rapid force sensing and cytoskeletal rearrangement. Cadherins contribute to long-term adhesion stability and signaling. Both adhesion types activate Rho GTPases to modulate contractility. The study emphasizes the importance of comparing integrin and cadherin pathways. The authors propose that crosstalk between these adhesion types is essential for cell function. They suggest that future work should focus on how these pathways interact in vivo. The findings provide a framework for understanding how cells respond to mechanical cues. The review supports the idea that force transmission is a highly regulated process.