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bioRxiv · 10.1101/2020.11.11.378273

Force requirements of endocytic vesicle formation

Abella Guerra, M.·Andruck, L.·Malengo, G.·Skruzny, M.
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Abstract

Mechanical forces are integral to many cellular processes, including clathrin-mediated endocytosis, a principal membrane trafficking route into the cell. During endocytosis, forces provided by endocytic proteins and the polymerizing actin cytoskeleton reshape the plasma membrane into a vesicle. Assessing force requirements of endocytic membrane remodelling is essential for understanding endocytosis. Here, we determined forces applied during endocytosis using FRET-based tension sensors integrated into the major force-transmitting protein Sla2 in yeast. We measured force of approx. 10 pN transmitted over Sla2 molecule, hence a total force of 450-1300 pN required for endocytic vesicle formation. Importantly, decreasing cell turgor pressure and plasma membrane tension reduced force requirements of endocytosis. The measurements in hypotonic conditions and mutants lacking BAR-domain membrane scaffolds then showed the limits of the endocytic force-transmitting machinery. Our study provides force values and force profiles critical for understanding the mechanics of endocytosis and potentially other key cellular membrane-remodelling processes.

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Abella Guerra, M., Andruck, L., Malengo, G., Skruzny, M.. 2020-11-11. Force requirements of endocytic vesicle formation. https://doi.org/10.1101/2020.11.11.378273

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