How circuit wiring is specified is a key question in developmental neurobiology. Previously, using the Drosophila motor system as a model, we found the classic temporal transcription factor, Hunchback acts in NB7-1 neuronal stem cells to control how many NB7-1 neuronal progeny form functional synapses on dorsal muscles (Meng et al., 2019). However, it is unknown to what extent control of motor neuron-to-muscle synaptic partnerships is a general feature of temporal transcription factors. Here, we perform additional temporal transcription factor manipulations—prolonging expression of Hunchback in NB3-1, as well as precociously expressing Pdm and Castor in NB7-1. We use confocal microscopy, calcium imaging, and electrophysiology to show that in every manipulation there are permanent alterations in neuromuscular synaptic partnerships. Our data show temporal transcription factors, as a group of molecules, are potent determinants of synaptic partner choice and therefore ultimately control circuit membership.
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 1, 1S2, 3, 4, 5.
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
© 2020, Meng et al.
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