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bioRxiv · 10.1101/2024.03.09.584267

DNA-based ForceChrono Probes for Deciphering Single-Molecule Force Dynamics in Living Cells

Hu, Y.·Li, H.·Zhang, C.·Feng, J.·Wang, W.·Chen, W.·Yu, M.·Zhang, X.·Liu, Z.
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Abstract

Accurate measurement of mechanical forces in cells is key to understanding how cells sense and respond to mechanical stimuli, a central aspect of mechanobiology. However, accurately quantifying dynamic forces at the single-molecule level in living cells is a significant challenge. Here, weve developed the DNA-based ForceChrono probe to enable in-depth studies of integrin force dynamics at the single-molecule level in living cells. By illuminating two distinct mechanical points and circumventing the inherent fluctuations of single-molecule fluorescence, the ForceChrono probe enables analysis of the complex dynamics of mechanical forces at the single-molecule level, such as loading rates and durations. Our results refine previous broad estimates of cellular loading rates to a more precise range of 0.5 to 2 pN/s, shedding light on the specifics of cellular mechanics. In addition, this study reveals a critical link between the magnitude and duration of integrin forces, consistent with the catch-bond behavior demonstrated in vitro. The ForceChrono probe has distinct advantages, such as precise analysis of single-molecule force dynamics and robust resistance to fluorescence fluctuations, which will significantly advance our understanding of cell adhesion and mechanotransduction at the single-molecule level.

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Hu, Y., Li, H., Zhang, C., Feng, J., Wang, W., Chen, W., Yu, M., Zhang, X., Liu, Z.. 2024-03-12. DNA-based ForceChrono Probes for Deciphering Single-Molecule Force Dynamics in Living Cells. https://doi.org/10.1101/2024.03.09.584267

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