Cryo-electron tomography of axons and varicosities in cultured primary mouse dorsal root ganglion neurons (baseline data and annotations)

Deposition Overview

Cryo-electron tomography of intact, unmilled peripheral axons and their varicosities in primary dorsal root ganglion neurons dissociated from 3-month-old mice and cultured for 48 h on gold Quantifoil grids. Neurons were plunge-frozen without fixation or staining, and the thin axonal processes growing over the grid were imaged directly. Most tilt series were collected on a Titan Krios at 300 kV with a Gatan energy filter and a K2 Summit detector; a comparative subset was collected on a Glacios at 200 kV with a Selectris energy filter and a Falcon 4i detector. No differences in structural information were noted between the two instruments and the data were pooled for analysis. Tomograms were reconstructed by weighted back-projection in IMOD and denoised by IsoNet deconvolution. Organelle membranes were pre-segmented with MemBrain-seg and microtubules with TARDIS-MT, then manually curated in Amira into a multi-class semantic scheme spanning the plasma membrane, microtubules, mitochondria, endoplasmic reticulum and vesicles enclosed within it, multivesicular bodies, multilamellar vesicles, endosomes, phagophores and free cytoplasmic vesicles. The deposition holds 105 tomograms, drawn from the 192 reconstructed for the study, together with their raw movies and tilt series; all of them carry a segmentation.