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bioRxiv · 10.1101/2022.06.20.496880

Direct Force Measurement and Loading on Developing Tissues in Intact Avian Embryos

Chan, C. U.·Xiong, F.·Michaut, A.·Pourquie, O.·Mahadevan, L.
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Abstract

Developmental morphogenesis is driven by tissue stresses acting on tissue rheology. Direct measurements of forces in small tissues (100m-1mm) in situ such as in early embryos require high spatial precision and minimal invasiveness. Here we report tissue force microscopy (TiFM) integrating a vertical cantilever probe and live imaging to enable close-loop control of mechanical loading in early chicken embryos. By testing previously qualitatively characterized force-producing tissues in the elongating body axis, we show that TiFM quantitatively captures stress dynamics with high sensitivity. TiFM also provides the capacity of applying a stable, minimally-invasive and physiologically relevant load to drive tissue deformation, which alters morphogenetic progression and cell movements. Together, TiFM addresses a key technological gap in tissue force measurement and manipulation in small developing embryos, and promises to contribute to the quantitative understanding of complex multi-tissue mechanics during development.

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Chan, C. U., Xiong, F., Michaut, A., Pourquie, O., Mahadevan, L.. 2022-06-21. Direct Force Measurement and Loading on Developing Tissues in Intact Avian Embryos. https://doi.org/10.1101/2022.06.20.496880

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