Nanoscale manipulation of membrane curvature for probing endocytosis in live cells

Nanoscale plasma membrane curvature, generated in a controllable fashion by vertically aligned nanostructure arrays, promotes the accumulation of key endocytic proteins in live cells. Clathrin-mediated endocytosis (CME) involves nanoscale bending and inward budding of the plasma membrane, by which cells regulate both the distribution of membrane proteins and the entry of extracellular species 1 , 2 . Extensive studies have shown that CME proteins actively modulate the plasma membrane curvature 1 , 3 , 4 . However, the reciprocal regulation of how the plasma membrane curvature affects the activities of endocytic proteins is much less explored, despite studies suggesting that membrane curvature itself can trigger biochemical reactions 5 , 6 , 7 , 8 . This gap in our understanding is largely due to technical challenges in precisely controlling the membrane curvature in live cells. In this work, we use patterned nanostructures to generate well-defined membrane curvatures ranging from +50 nm to −500 nm radius of curvature. We find that the positively curved membranes are CME hotspots, and that key CME proteins, clathrin and dynamin, show a strong preference towards positive membrane curvatures with a radius