Cryo-electron tomography of a cryo-FIB lift-out from adult mouse hippocampal CA1 stratum pyramidale

This dataset contains in situ cryo-electron tomography of vitreous adult mouse (C57BL/6J) hippocampal tissue targeting the pyramidal cell layer (stratum pyramidale) of the CA1 field. A 100 um sagittal slice from the right hemisphere of a 172-day-old female mouse was high-pressure frozen after a 20 min incubation with a dextran/sucrose cryoprotectant in an NMDG-based buffer, screened by cryo-fluorescence/cryo-confocal microscopy, and the CA1 stratum pyramidale was targeted by plasma focused-ion-beam (PFIB) milling using the band of Hoechst-stained pyramidal cell nuclei as the fluorescent landmark. Serial cryo-lift-out sections were welded onto TEM support grids and thinned to lamellae that remained comparatively thick, sampling neuronal cell bodies and the adjacent neuropil - nuclei with distinguishable heterochromatin and euchromatin, dense fields of ribosomes, mitochondria and vesicles - at the cost of lower-contrast tilt series. Tilt series were acquired on a Titan Krios G4 (300 kV) with a Selectris energy filter and Falcon 4i detector.