In situ fiducial markers for 3D correlative cryo-fluorescence and FIB-SEM imaging

Summary: Imaging of cells and tissues has improved significantly over the last decade. Dual-beam instruments with a focused ion beam mounted on a scanning electron microscope (FIB-SEM), offering high-resolution 3D imaging of large volumes and fields-of-view are becoming widely used in the life scien...

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Bibliographic Details
Main Authors: Nadav Scher, Katya Rechav, Perrine Paul-Gilloteaux, Ori Avinoam
Format: Article
Language:English
Published: Elsevier 2021-07-01
Series:iScience
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S2589004221006829
Description
Summary:Summary: Imaging of cells and tissues has improved significantly over the last decade. Dual-beam instruments with a focused ion beam mounted on a scanning electron microscope (FIB-SEM), offering high-resolution 3D imaging of large volumes and fields-of-view are becoming widely used in the life sciences. FIB-SEM has most recently been implemented on fully hydrated, cryo-immobilized, biological samples. Correlative light and electron microscopy workflows combining fluorescence microscopy (FM) with FIB-SEM imaging exist, whereas workflows combining cryo-FM and cryo-FIB-SEM imaging are not yet commonly available. Here, we demonstrate that fluorescently labeled lipid droplets can serve as in situ fiducial markers for correlating cryo-FM and FIB-SEM datasets and that this approach can be used to target the acquisition of large FIB-SEM stacks spanning tens of microns under cryogenic conditions. We also show that cryo-FIB-SEM imaging is particularly informative for questions related to organelle structure and inter-organellar contacts, nuclear organization, and mineral deposits in cells.
ISSN:2589-0042