Dendrite architecture determines mitochondrial distribution patterns in vivo

• Published in: Cell reports (Cambridge) 2024-05, Vol.43 (5), p.114190, Article 114190
• Main Authors: Donovan, Eavan J., Agrawal, Anamika, Liberman, Nicole, Kalai, Jordan I., Adler, Avi J., Lamper, Adam M., Wang, Hailey Q., Chua, Nicholas J., Koslover, Elena F., Barnhart, Erin L.
• Format: Article
• Language: English
• Subjects: Animals; dendrite scaling; Dendrites - metabolism; Drosophila - metabolism; Drosophila melanogaster - metabolism; in vivo imaging; Mitochondria - metabolism; mitochondrial motility; neuronal morphology; Neurons - metabolism
• ISSN: 2211-1247; 2211-1247
• DOI: 10.1016/j.celrep.2024.114190

Neuronal morphology influences synaptic connectivity and neuronal signal processing. However, it remains unclear how neuronal shape affects steady-state distributions of organelles like mitochondria. In this work, we investigated the link between mitochondrial transport and dendrite branching patterns by combining mathematical modeling with in vivo measurements of dendrite architecture, mitochondrial motility, and mitochondrial localization patterns in Drosophila HS (horizontal system) neurons. In our model, different forms of morphological and transport scaling rules—which set the relative thicknesses of parent and daughter branches at each junction in the dendritic arbor and link mitochondrial motility to branch thickness—predict dramatically different global mitochondrial localization patterns. We show that HS dendrites obey the specific subset of scaling rules that, in our model, lead to realistic mitochondrial distributions. Moreover, we demonstrate that neuronal activity does not affect mitochondrial transport or localization, indicating that steady-state mitochondrial distributions are hard-wired by the architecture of the neuron. [Display omitted] •A model for transport in dendrites predicts global mitochondrial localization patterns•In this model, specific scaling rules recapitulate realistic mitochondrial distributions•Drosophila HS dendrites obey these specific scaling rules Donovan et al. combine mathematical modeling with in vivo measurements of mitochondrial transport and neuronal architecture in Drosophila HS (horizontal system) neurons to demonstrate that global, steady-state mitochondrial localization patterns depend on specific dendrite branch scaling rules.