Postsynaptic plasticity of cholinergic synapses underlies the induction and expression of appetitive and familiarity memories in Drosophila
- Charité - Universitätsmedizin Berlin, Germany
- Freie Universität Berlin, Germany
- University of Greifswald, Germany
Abstract
In vertebrates, several forms of memory-relevant synaptic plasticity involve postsynaptic rearrangements of glutamate receptors. In contrast, previous work indicates that Drosophila and other invertebrates store memories using presynaptic plasticity of cholinergic synapses. Here, we provide evidence for postsynaptic plasticity at cholinergic output synapses from the Drosophila mushroom bodies (MBs). We find that the nicotinic acetylcholine receptor (nAChR) subunit α5 is required within specific MB output neurons (MBONs) for appetitive memory induction, but is dispensable for aversive memories. In addition, nAChR α2 subunits mediate memory expression and likely function downstream of α5 and the postsynaptic scaffold protein Dlg. We show that postsynaptic plasticity traces can be induced independently of the presynapse, and that in vivo dynamics of α2 nAChR subunits are changed both in the context of associative and non-associative (familiarity) memory formation, underlying different plasticity rules. Therefore, regardless of neurotransmitter identity, key principles of postsynaptic plasticity support memory storage across phyla.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Raquel Suárez-Grimalt
Funding
Deutsche Forschungsgemeinschaft (390688087)
- David Owald
Deutsche Forschungsgemeinschaft (184695641)
- David Owald
Deutsche Forschungsgemeinschaft (327654276)
- David Owald
Deutsche Forschungsgemeinschaft (365082554)
- David Owald
Deutsche Forschungsgemeinschaft
- Sridhar R Jagannathan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Pribbenow 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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Postsynaptic plasticity of cholinergic synapses underlies the induction and expression of appetitive and familiarity memories in Drosophila
eLife 11:e80445.
https://doi.org/10.7554/eLife.80445
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