Sequential formation of Drosophila circuit asymmetry via prolonged structural plasticity.

Markovitsch, J. W.; Mitic, D.; Garcia, A. d. P. J.; Alsberga, Z.; Kainz, S.; Kaur, R.; Hummel, T.

doi:10.1101/2025.05.27.656373

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bioRxiv · 10.1101/2025.05.27.656373

Sequential formation of Drosophila circuit asymmetry via prolonged structural plasticity.

Markovitsch, J. W.·Mitic, D.·Garcia, A. d. P. J.·Alsberga, Z.·Kainz, S.·Kaur, R.·Hummel, T.

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Abstract

Structural and functional differences between brain hemispheres are a common feature of animal nervous systems with reduced bilateral asymmetry often linked to impaired cognitive performance. How neuronal left-right asymmetry is initiated and integrated into a bilaterally symmetrical ground pattern is poorly understood. Here we show that directional asymmetry of a Drosophila central brain circuit originates from axonal interactions of two classes of bilateral pioneer neurons. Subsequent recruitment of neighboring neuron classes into the asymmetric neuropil precursor results in hemisphere-specific microcircuits. Circuit lateralization requires dynamic expression of the cell adhesion molecule Fasciclin 2 to maintain structural plasticity in axonal remodeling. Reduced circuit asymmetry following cell type-specific Fasciclin 2 manipulation affect adult brain function. These results reveal an unexpected degree of developmental plasticity of late-born Drosophila neurons in the formation of a new circuit node via the lateralized recruitment of symmetric circuit components.

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Markovitsch, J. W., Mitic, D., Garcia, A. d. P. J., Alsberga, Z., Kainz, S., Kaur, R., Hummel, T.. 2025-05-30. Sequential formation of Drosophila circuit asymmetry via prolonged structural plasticity.. https://doi.org/10.1101/2025.05.27.656373

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