Anatomy and activity patterns in a multifunctional motor neuron and its surrounding circuits
- California Institute of Technology, United States
- Keio University, Japan
- University of California, San Diego, United States
Abstract
Dorsal Excitor motor neuron DE-3 in the medicinal leech plays three very different dynamical roles in three different behaviors. Without rewiring its anatomical connectivity, how can a motor neuron dynamically switch roles to play appropriate roles in various behaviors? We previously used voltage-sensitive dye imaging to record from DE-3 and most other neurons in the leech segmental ganglion during (fictive) swimming, crawling, and local-bend escape (Tomina and Wagenaar, 2017). Here, we repeated that experiment, then re-imaged the same ganglion using serial blockface electron microscopy and traced DE-3's processes. Further, we traced back the processes of DE-3's presynaptic partners to their respective somata. This allowed us to analyze the relationship between circuit anatomy and the activity patterns it sustains. We found that input synapses important for all of the behaviors were widely distributed over DE-3's branches, yet that functional clusters were different during (fictive) swimming vs. crawling.
Data availability
The easiest way to access the raw electrophysiology and voltage-dye data as well as the tracing results used in this paper is through a series of Python modules that we made available at https://github.com/wagenadl/leechem-public. Included in the package is a file called "demo.py" that demonstrates the use of the modules. Table 4 lists the available VSD trials.The aligned EM volume may be accessed through the Neuroglancer instance at https://leechem.caltech.edu or by pointing SBEMViewer to https://leechem.caltech.edu/emdata.The code used for alignment is available at https://github.com/wagenadl/sbemalign. Our visualization tools SBEMViewer and GVox are at https://github.com/wagenadl/sbemviewer and https://github.com/wagenadl/gvox.
Article and author information
Author details
Funding
National Institute of Neurological Disorders and Stroke (R01-NS094403)
- William B Kristan Jnr
- Mark H Ellisman
- Daniel A Wagenaar
National Institute of General Medical Sciences (P41-GM103412)
- Mark H Ellisman
Japan Society for the Promotion of Science (201800526)
- Yusuke Tomina
Japan Society for the Promotion of Science (19K16191)
- Yusuke Tomina
Swiss National Science Foundation (P2EZP3-181896)
- Pegah Kassraian
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Ashaber et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Anatomy and activity patterns in a multifunctional motor neuron and its surrounding circuits
eLife 10:e61881.
https://doi.org/10.7554/eLife.61881
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