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Title: Morphological principles of neuronal mitochondria
In the highly dynamic metabolic landscape of a neuron, mitochondrial membrane architectures can provide critical insight into the unique energy balance of the cell. Current theoretical calculations of functional outputs like ATP and heat often represent mitochondria as idealized geometries and therefore can miscalculate the metabolic fluxes. To analyze mitochondrial morphology in neurons of mouse cerebellum neuropil, 3D tracings of complete synaptic and axonal mitochondria were constructed using a database of serial TEM tomographyimages and converted to watertight meshes with minimal distortion of the original microscopy volumes with agranularity of 1.6 nanometer isotropic voxels. The resulting in silico representations were subsequently quantified by differential geometry methods in terms of the mean and Gaussian curvatures, surface areas, volumes, and membrane motifs, all of which can alter the metabolic output of the organelle. Finally, we identify structural motifs that are present across this population of mitochondria; observations which may contribute to future modeling studies of mitochondrial physiology and metabolism in neurons.
Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ;
Award ID(s):
2014862
Publication Date:
NSF-PAR ID:
10250923
Journal Name:
bioRxiv
ISSN:
2692-8205
Sponsoring Org:
National Science Foundation
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     STUDY FUNDING/COMPETING INTEREST(S)

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