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bioRxiv · 10.1101/2021.05.09.443230

Multi-color 4D superresolution light-sheet microscopy reveals organelle interactions at isotropic 100-nm resolution and sub-second timescales

Fei, P.
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Abstract

Long-term visualization of the dynamic organelle-organelle or protein-organelle interactions throughout the three-dimensional space of whole live cells is essential to better understand their functions, but this task remains challenging due to the limitations of existing three-dimensional fluorescence microscopy techniques, such as an insufficient axial resolution, low volumetric imaging rate, and photobleaching. Here, we present the combination of a progressive deep-learning superresolution strategy with a dual-ring-modulated SPIM design capable of visualizing the dynamics of intracellular organelles in live cells for hours at an isotropic spatial resolution of [~]100 nm in three dimensions and a temporal resolution up to [~]17 Hz. With a compelling spatiotemporal resolution, we substantially reveal the complex spatial relationships and interactions between the endoplasmic reticulum (ER) and mitochondria throughout live cells, providing new insights into ER-mediated mitochondrial division. We also localized the motion of Drp1 oligomers in three dimensions and observed Drp1-mediated mitochondrial branching for the first time.

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Fei, P.. 2021-05-10. Multi-color 4D superresolution light-sheet microscopy reveals organelle interactions at isotropic 100-nm resolution and sub-second timescales. https://doi.org/10.1101/2021.05.09.443230

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