A cryo-ET survey of microtubules and intracellular compartments in mammalian axons

DOI: 10.1083/jcb.202103154

Authors: Helen E. Foster (MRC Laboratory of Molecular Biology) , Camilla Ventura Santos (MRC Laboratory of Molecular Biology) , Andrew P. Carter (MRC Laboratory of Molecular Biology)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Journal Of Cell Biology , VOL 221

State: Published (Approved)
Published: February 2022
Diamond Proposal Number(s): 23268 , 17434

Abstract: The neuronal axon is packed with cytoskeletal filaments, membranes, and organelles, many of which move between the cell body and axon tip. Here, we used cryo-electron tomography to survey the internal components of mammalian sensory axons. We determined the polarity of the axonal microtubules (MTs) by combining subtomogram classification and visual inspection, finding MT plus and minus ends are structurally similar. Subtomogram averaging of globular densities in the MT lumen suggests they have a defined structure, which is surprising given they likely contain the disordered protein MAP6. We found the endoplasmic reticulum in axons is tethered to MTs through multiple short linkers. We surveyed membrane-bound cargos and describe unexpected internal features such as granules and broken membranes. In addition, we detected proteinaceous compartments, including numerous virus-like capsid particles. Our observations outline novel features of axonal cargos and MTs, providing a platform for identification of their constituents.

Subject Areas: Biology and Bio-materials

Diamond Offline Facilities: Electron Bio-Imaging Centre (eBIC)
Instruments: Krios I-Titan Krios I at Diamond

Added On: 14/09/2022 10:33

Documents:
jcb_202103154.pdf

Discipline Tags:

Health & Wellbeing Neurology Structural biology Life Sciences & Biotech

Technical Tags:

Imaging Tomography Cryo Electron Tomography (Cryo ET)