Imaging intracellular components in situ using super-resolution cryo-correlative light and electron microscopy

Abstract

Super-resolution cryo-correlative light and electron microscopy (SRcryoCLEM) is emerging as a powerful method to enable targeted in situ structural studies of biological samples. By combining the high specificity and localization accuracy of single-molecule localization microscopy (cryoSMLM) with the high resolution of cryo-electron tomography (cryoET), this method enables accurately targeted data acquisition and the observation and identification of biomolecules within their natural cellular context. Despite its potential, the adaptation of SRcryoCLEM has been hindered by the need for specialized equipment and expertise. In this chapter, we outline a workflow for cryoSMLM and cryoET-based SRcryoCLEM, and we demonstrate that, given the right tools, it is possible to incorporate cryoSMLM into an established cryoET workflow. Using Vimentin as an exemplary target of interest, we demonstrate all stages of an SRcryoCLEM experiment: performing cryoSMLM, targeting cryoET acquisition based on single-molecule localization maps, and correlation of cryoSMLM and cryoET datasets using scNodes, a software package dedicated to SRcryoCLEM. By showing how SRcryoCLEM enables the imaging of specific intracellular components in situ, we hope to facilitate adoption of the technique within the field of cryoEM.

Keywords: CLEM; Correlative light-electron microscopy; Cryo-electron tomography; SRcryoCLEM; Super-resolution light microscopy; cryoEM.