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bioRxiv · 10.1101/2021.11.21.469320

Laser Ablation and Fluid Flows Show a Single Force Mechanism Governs Spindle Positioning

Wu, H.-Y.·Kabacaoglu, G.·Nazockdast, E.·Chang, H.-C.·Shelley, M. J.·Needleman, D. J.
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Abstract

Few techniques are available for elucidating the nature of forces that drive subcellular behaviors. Here we develop two complementary ones: 1) femtosecond stereotactic laser ablation (FESLA), which rapidly creates complex cuts of subcellular structures, thereby allowing precise dissection of when, where, and in what direction forces are generated; and 2) assessment of subcellular fluid flows, by comparing direct flow measurements, using microinjected fluorescent nanodiamonds, to large-scale fluid-structure simulations of different models of force transduction. We apply these to study centrosomes in Caenorhabditis elegans early embryos, and use the data to construct a biophysically-based model of centrosome dynamics. Taken together, we demonstrate that cortical pulling forces provide a general explanation for many behaviors mediated by centrosomes, including pronuclear migration/centration and rotation, metaphase spindle positioning, asymmetric spindle elongation and spindle oscillations. In sum, this work establishes new methodologies for disentangling the forces responsible for cell biological phenomena.

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Wu, H.-Y., Kabacaoglu, G., Nazockdast, E., Chang, H.-C., Shelley, M. J., Needleman, D. J.. 2021-11-22. Laser Ablation and Fluid Flows Show a Single Force Mechanism Governs Spindle Positioning. https://doi.org/10.1101/2021.11.21.469320

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