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bioRxiv · 10.1101/209791

Morphological changes of plasma membrane and protein assembly during clathrin-mediated endocytosis

Yoshida, A.·Sakai, N.·Uekusa, Y.·Imaoka, Y.·Itagaki, Y.·Suzuki, Y.·Yoshimura, S. H.
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Abstract

Clathrin-mediated endocytosis (CME) proceeds through a series of morphological changes of the plasma membrane induced by a number of protein components. Although the spatiotemporal assembly of these proteins has been elucidated by fluorescence-based techniques, the protein-induced morphological changes of the plasma membrane have not been fully clarified in living cells. Here we visualize membrane morphology together with protein localizations during CME by utilizing high-speed atomic force microscopy combined with a confocal laser scanning unit. The plasma membrane starts to invaginate ~30 seconds after clathrin starts to assemble, and the aperture diameter increases as clathrin accumulates. Actin rapidly accumulates around the pit and induces a small membrane swelling, which within 30 seconds rapidly covers the pit irreversibly. Inhibition of actin turnover abolishes the swelling and induces a reversible open-close motion of the pit, indicating that actin dynamics are necessary for efficient and irreversible pit closure at the end of the CME.

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Yoshida, A., Sakai, N., Uekusa, Y., Imaoka, Y., Itagaki, Y., Suzuki, Y., Yoshimura, S. H.. 2017-10-31. Morphological changes of plasma membrane and protein assembly during clathrin-mediated endocytosis. https://doi.org/10.1101/209791

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