How prolonged expression of Hb, a temporal transcription factor, re-wires locomotor circuits
How circuits assemble starting from stem cells is a fundamental question in developmental neurobiology. We test the hypothesis that, in neuronal stem cells, temporal transcription factors predictably control neuronal terminal features and circuit assembly. Using the Drosophila motor system, we manipulate expression of the classic temporal transcription factor, Hunchback (Hb) specifically in the NB7-1 stem cell, which produces U motor neurons (MNs), and then we monitor dendrite morphology and neuromuscular synaptic partnerships. We find that prolonged expression of Hb leads to transient specification of U MN identity, and that embryonic molecular markers do not accurately predict U MN terminal features. Nonetheless, our data show Hb acts as a potent regulator of neuromuscular wiring decisions. These data introduce important refinements to current models, show that molecular information acting early in neurogenesis as a switch to control motor circuit wiring and provide novel insight into the relationship between stem cell and circuit.
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
National Institute of Neurological Disorders and Stroke (R01-NS105748)
- Ellie S Heckscher
National Institute of General Medical Sciences (T32 GM007183)
- Julia L Meng
National Science Foundation (DGE-1746045)
- Julia L Meng
University of Chicago
- Ellie S Heckscher
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Oliver Hobert, Howard Hughes Medical Institute, Columbia University, United States
- Received: February 14, 2019
- Accepted: September 9, 2019
- Accepted Manuscript published: September 10, 2019 (version 1)
- Version of Record published: September 20, 2019 (version 2)
© 2019, Meng 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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