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bioRxiv · 10.1101/2021.02.26.433056

3D Neuronal Mitochondrial Morphology in Axons, Dendrites, and Somata of the Aging Mouse Hippocampus

Faitg, J.·Lacefield, C.·Davey, T.·White, K.·Laws, R.·Kosmidis, S.·Reeve, A. K.·Kandel, E.·Vincent, A. E.·Picard, M.
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Abstract

The brains ability to process complex informations relies on the constant supply of energy through aerobic respiration by mitochondria. Neurons contain three anatomically distinct compartments - the soma, dendrites, and projecting axons - which have different energetic and biochemical requirements, as well as different mitochondrial morphologies in cultured systems. Here we apply a quantitative three-dimensional electron microscopy approach to map mitochondrial network morphology and complexity in the mouse brain. We examine three neuronal sub-compartments - the soma, dendrites, myelinated axons - in the dentate gyrus and CA1 of the mouse hippocampus, two subregions with distinct principal cell types and functions. We also establish compartment-specific differences in mitochondrial morphology across these cell types between young and old mice, highlighting differences in age-related morphological recalibrations. Overall, these data define the nature of the neuronal mitochondrial network in the mouse hippocampus, providing a foundation to examine the role of mitochondrial morpho-function in the aging brain.

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Faitg, J., Lacefield, C., Davey, T., White, K., Laws, R., Kosmidis, S., Reeve, A. K., Kandel, E., Vincent, A. E., Picard, M.. 2021-02-27. 3D Neuronal Mitochondrial Morphology in Axons, Dendrites, and Somata of the Aging Mouse Hippocampus. https://doi.org/10.1101/2021.02.26.433056

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