A multiplexed tension sensor reveals the distinct levels of integrin-mediated forces in adherent cells

Integrins are crucial for cell adhesion, spreading, and cell-cell interactions, contributing significantly to cellular functions. Various tension sensors have been developed to measure integrin tensions across different cell types and conditions. However, there is a lack of tools to accurately calibrate the high-level force range of integrins required for cell adhesion. In this study, we engineered a multiplexed tension sensor (TS) by combining a yellow fluorescence protein tension sensor (YFP TS) with a DNA integrative tension sensor (ITS) previously used. This innovative approach enabled us to detect integrin-mediated forces in adherent cells. Our findings revealed that high-motile fish keratocytes exhibited integrin-mediated forces ranging from 44 to 100 pN, whereas low-motile 3T3L1 and NRK cells generated integrin-mediated forces exceeding 100 pN. This difference may be attributed to the shorter dwelling time or interaction time between an integrin and a RGD ligand in keratocytes, suggesting a need to examine the loading rate information for the integrin and the ligand in focal adhesions.