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bioRxiv · 10.1101/2024.05.01.592061

Brain rewiring during developmental transitions: A Comparative Analysis of Larva and Adult Drosophila melanogaster

Yadav, P.·Shinde, P.·Singh, A.
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Abstract

The brains ability to adapt through structural rewiring during developmental transitions is a fundamental aspect of neuroscience. Our study conducts a detailed comparison of Drosophila melanogaster s brain networks during larval and adult stages, revealing significant changes in neuronal wiring during developmental phases. The degree distribution of the larval brain deviates significantly from power-law behavior and fits well with the Weibull distribution. In contrast, the adult brain exhibits power-law behavior in its degree distribution, with the exponent for the out-degree distribution lying in the scale-free regime and the exponent for the in-degree distribution being close to this regime. This difference reflects a change in the robustness of brain development from larval to adult phases. The core of these networks also changes during development in terms of their cell composition and topological influence. The larval core comprises Mushroom Body neurons, while the adult core mainly has Antennal Lobe neurons. Moreover, all the core neurons in the larval brain are also part of the rich-club neurons, a group of neurons with high in/out degrees that are well connected, whereas the same is not true for the adult brain network. Additionally, the core of the larval brain displays a more heterogeneous connectivity profile in its second-order neighbors compared to adult brain neurons, indicating greater diversity in larval brain connectivity. Our work stands as a step forward in understanding the rewiring of brain networks across the life stages of Drosophila melanogaster.

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Yadav, P., Shinde, P., Singh, A.. 2024-05-01. Brain rewiring during developmental transitions: A Comparative Analysis of Larva and Adult Drosophila melanogaster. https://doi.org/10.1101/2024.05.01.592061

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