Presynaptic developmental plasticity allows robust sparse wiring of the Drosophila mushroom body
Abstract
In order to represent complex stimuli, principle neurons of associative learning regions receive combinatorial sensory inputs. Density of combinatorial innervation is theorized to determine the number of distinct stimuli that can be represented and distinguished from one another, with sparse innervation thought to optimize the complexity of representations in networks of limited size. How the convergence of combinatorial inputs to principle neurons of associative brain regions is established during development is unknown. Here, we explore the developmental patterning of sparse olfactory inputs to Kenyon cells of the Drosophila melanogaster mushroom body. By manipulating the ratio between pre- and post-synaptic cells, we find that postsynaptic Kenyon cells set convergence ratio: Kenyon cells produce fixed distributions of dendritic claws while presynaptic processes are plastic. Moreover, we show that sparse odor responses are preserved in mushroom bodies with reduced cellular repertoires, suggesting that developmental specification of convergence ratio allows functional robustness.
Data availability
Analyzed data points generated during the study are included in the figures. Source data for Figure 7 is presented in a source data file.
Article and author information
Author details
Funding
Rita Allen Foundation (Milton Cassel Scholar)
- E Josie Clowney
Alfred P. Sloan Foundation (Research Fellow in Neuroscience)
- E Josie Clowney
University of Michigan (Startup Funds)
- E Josie Clowney
University of Michigan (Neuroscience Scholar Award)
- E Josie Clowney
Helen Hay Whitney Foundation (Simons Fellow)
- E Josie Clowney
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Elkahlah 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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