Fly connectome simulations identify a candidate three-neuron walking rhythm circuit
Published in Brain Architecture & Maps, Brain/Neurology, Journals, Numerical Simulations.
Published October 29, 2026.
Simulations built from fly nerve-cord connectomes have identified a candidate circuit for generating walking rhythms. Pugliese and colleagues published the study in Nature on October 28.
The researchers simulated the connections in the Drosophila ventral nerve cord and screened descending inputs from the brain. DNg100, a known walking command neuron, was the strongest simulated driver of rhythmic leg motor activity.
Progressively reducing the simulated network isolated a circuit of three interneurons: one inhibitory and two excitatory. Within the models, this circuit was necessary and sufficient for motor rhythms across all six legs, with results reproduced in four connectome datasets.
The simulations also predicted that another descending pathway, DNb08, could drive rhythmic leg movements. The team tested that prediction experimentally using optogenetics in flies.
The work illustrates how anatomical connectivity can guide functional circuit hypotheses. The minimal pattern generator remains a putative biological circuit: necessity and sufficiency in a simulation do not establish every corresponding property in a living animal.
Source: Pugliese et al., Nature. Published October 28, 2026. DOI: 10.1038/s41586-026-11195-y.