Nanoscale manipulation of membrane curvature for probing endocytosis in live cells

• Published in: Nature nanotechnology Vol. 12; no. 8; pp. 750 - 756
• Main Authors: Zhao, Wenting, Hanson, Lindsey, Lou, Hsin-Ya, Akamatsu, Matthew, Chowdary, Praveen D., Santoro, Francesca, Marks, Jessica R., Grassart, Alexandre, Drubin, David G., Cui, Yi, Cui, Bianxiao
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-08-2017; Nature Publishing Group
• Subjects: 142/126; 142/136; 147/135; 147/143; 147/28; 631/61/350/2093; 639/925/350/2093; Caveolin 1 - metabolism; Cell Line; Cell Membrane - metabolism; Clathrin; Clathrin - metabolism; Dynamin; Dynamins - metabolism; Endocytosis; Humans; letter; Materials Science; Membrane proteins; Membranes; Nanostructure; Nanostructures - chemistry; Nanotechnology; Nanotechnology and Microengineering; Plasmas (physics); Preferences; Proteins; Radius of curvature; Substrates
• ISSN: 1748-3387; 1748-3395
• DOI: 10.1038/nnano.2017.98

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
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. Extensive studies have shown that CME proteins actively modulate the plasma membrane curvature
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. 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
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. 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 <200 nm. Of ten CME-related proteins we examined, all show preferences for positively curved membrane. In contrast, other membrane-associated proteins and non-CME endocytic protein caveolin1 show no such curvature preference. Therefore, nanostructured substrates constitute a novel tool for investigating curvature-dependent processes in live cells.