Markovitsch, J.W., Mitić, D., Del Pilar Jiménez García, A., Alsberga, Z., Kainz, S., Kaur, R., Hummel, T. (2026). Sequential formation of Drosophila circuit asymmetry via prolonged structural plasticity.  Sci. Adv. 12(13): eaea6020.

FBrf0265024

Research paper

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 the directional asymmetry of a Drosophila central brain circuit originates from axonal interactions of two types of bilateral pioneer neurons. Subsequent recruitment of neighboring neurons into the asymmetric neuropil primordium 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 affects adult brain function. These results reveal an unexpected degree of developmental plasticity of late-born Drosophila neurons in the formation of a circuit node via the lateralized recruitment of symmetric circuit components.

PMC13015903 (PMC) (EuropePMC)