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bioRxiv · 10.1101/2020.12.08.417063

Heterogenous adhesion of follower cells affects tension profile and velocity of leader cells in primary keratocyte collective cell migration

Mukherjee, B.·Chakraborty, M.·Biswas, A.·Nayak, R. K.·Sinha, B.
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Abstract

Single cell studies demonstrate membrane tension to be a central regulator of lamellipodia-driven motility bringing in front-coherence. During collective cell migration, however, tension mapping or existence of intracellular tension-gradients and the effect of cell-cell interactions have remained unexplored. In this study of membrane fluctuations and fluctuation-tension of migrating primary keratocyte cell-sheets, we first show that some leader cells are followed by followers which remain de-adhered from the substrate while being attached to other cells and thus appear to be "taking a ride". A subtle yet significant enhanced long-timescale velocity in these leaders indicate increased directionality. Intriguingly, such leaders mostly have front-high tension gradients like single keratocytes, while followers and other leaders usually display front-low membrane tension gradients. The front-high tension gradient and higher membrane tension observed in these leaders, despite the high cell-to-cell variability in membrane tension demonstrate how leader-follower interactions and heterogenous adhesion profiles are key in collective cell migration.

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Mukherjee, B., Chakraborty, M., Biswas, A., Nayak, R. K., Sinha, B.. 2020-12-09. Heterogenous adhesion of follower cells affects tension profile and velocity of leader cells in primary keratocyte collective cell migration. https://doi.org/10.1101/2020.12.08.417063

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