Reconstruction of motor control circuits in adult Drosophila using automated transmission electron microscopy

Maniates-Selvin, J. T.; Hildebrand, D. G. C.; Graham, B. J.; Kuan, A. T.; Thomas, L. A.; Nguyen, T.; Buhmann, J.; Azevedo, A. W.; Shanney, B. L.; Funke, J.; Tuthill, J. C.; Lee, W.-C. A.

doi:10.1101/2020.01.10.902478

bioRxiv · 10.1101/2020.01.10.902478

Reconstruction of motor control circuits in adult Drosophila using automated transmission electron microscopy

Maniates-Selvin, J. T.·Hildebrand, D. G. C.·Graham, B. J.·Kuan, A. T.·Thomas, L. A.·Nguyen, T.·Buhmann, J.·Azevedo, A. W.·Shanney, B. L.·Funke, J.·Tuthill, J. C.·Lee, W.-C. A.

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Abstract

Many animals use coordinated limb movements to interact with and navigate through the environment. To investigate circuit mechanisms underlying locomotor behavior, we used serial-section electron microscopy (EM) to map synaptic connectivity within a neuronal network that controls limb movements. We present a synapse-resolution EM dataset containing the ventral nerve cord (VNC) of an adult female Drosophila melanogaster. To generate this dataset, we developed GridTape, a technology that combines automated serial-section collection with automated high-throughput transmission EM. Using this dataset, we reconstructed 507 motor neurons, including all those that control the legs and wings. We show that a specific class of leg sensory neurons directly synapse onto the largest-caliber motor neuron axons on both sides of the body, representing a unique feedback pathway for fast limb control. We provide open access to the dataset and reconstructions registered to a standard atlas to permit matching of cells between EM and light microscopy data. We also provide GridTape instrumentation designs and software to make large-scale EM data acquisition more accessible and affordable to the scientific community.

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Maniates-Selvin, J. T., Hildebrand, D. G. C., Graham, B. J., Kuan, A. T., Thomas, L. A., Nguyen, T., Buhmann, J., Azevedo, A. W., Shanney, B. L., Funke, J., Tuthill, J. C., Lee, W.-C. A.. 2020-01-11. Reconstruction of motor control circuits in adult Drosophila using automated transmission electron microscopy. https://doi.org/10.1101/2020.01.10.902478

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