Analysis of Heteroсhromatin Mesoscale Architecture by Cryo-Electron Tomography

Cryo-ET (cryo-electron tomography) is a powerful tool for studying the structure of biological objects in their native state. However, Cryo-ET is still not widely used to study cellular organelles including cell nucleus and chromatin in situ. In our work, we aimed to investigate the possibilities of employing cryo-ET for studying the architecture of natively preserved chromatin, focusing on the possibility of using a cryoCLEM (cryo-correlative light and electron microscopy) approach to target final steps of sample preparation by focused ion beam (FIB) milling exactly to the area of interest, namely, heterochromatin loci.