PT  - JOURNAL ARTICLE
AU  - Noa Bielopolski
AU  - Hoger Amin
AU  - Anthi A. Apostolopoulou
AU  - Eyal Rozenfeld
AU  - Hadas Lerner
AU  - Wolf Huetteroth
AU  - Andrew C. Lin
AU  - Moshe Parnas
TI  - Inhibitory muscarinic acetylcholine receptors enhance aversive olfactory conditioning in adult Drosophila
AID  - 10.1101/382440
DP  - 2018 Jan 01
TA  - bioRxiv
PG  - 382440
4099  - http://biorxiv.org/content/early/2018/08/01/382440.short
4100  - http://biorxiv.org/content/early/2018/08/01/382440.full
AB  - Olfactory associative learning in Drosophila is mediated by synaptic plasticity between the Kenyon cells of the mushroom body and their output neurons. Both Kenyon cells and their inputs are cholinergic, yet little is known about the physiological function of muscarinic acetylcholine receptors in learning in adult flies. Here we show that aversive olfactory learning in adult flies requires type A muscarinic acetylcholine receptors (mAChR-A) specifically in the gamma subtype of Kenyon cells. Surprisingly, mAChR-A inhibits odor responses in both Kenyon cell dendrites and axons. Moreover, mAChR-A knockdown impairs the learning-associated depression of odor responses in a mushroom body output neuron. Our results suggest that mAChR-A is required at Kenyon cell presynaptic terminals to depress the synapses between Kenyon cells and their output neurons, and may suggest a role for the recently discovered axo-axonal synapses between Kenyon cells.