106 Oral - Neurodevelopment II/Neurobehavior II
Friday April 08, 5:00 PM - 5:15 PM

Associative learning drives longitudinally-graded presynaptic plasticity of neurotransmitter release along axonal compartments


Authors:
Aaron Stahl 1; Nathaniel Noyes 1; Tamara Boto 2; Miao Jing 3; Jianzhi Zeng 4,5,6; Lanikea King 1; Yulong Li 3,4,5,6; Ronald Davis 1; Seth Tomchik 1

Affiliations:
1) The Scripps Research Institute, Jupiter, FL; 2) Trinity College, Dublin, Ireland ; 3) Chinese Institute for Brain Research, Beijing, China; 4) State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China; 5) Peking-Tsinghua Center for Life Sciences, Beijing, China; 6) PKU- IDG/McGovern Institute for Brain Research, Beijing, China

Keywords:
a. neurotransmitters; v. live imaging

Anatomical and physiological compartmentalization of neurons is a mechanism to increase the computational capacity of a circuit, and a major question is what role axonal compartmentalization plays. Axonal compartmentalization may enable localized, presynaptic plasticity to alter neuronal output in a flexible, experience-dependent manner. Here we show that olfactory learning generates compartmentalized, bidirectional plasticity of acetylcholine release that varies across the longitudinal compartments of Drosophila mushroom body (MB) axons. The directionality of the learning-induced plasticity depends on the valence of the learning event (aversive vs. appetitive), varies linearly across proximal to distal compartments following appetitive conditioning, and correlates with learning-induced changes in downstream mushroom body output neurons (MBONs) that modulate behavioral action selection. Potentiation of acetylcholine release was dependent on the CaV2.1 calcium channel subunit cacophony. In addition, contrast between the positive conditioned stimulus and other odors required the inositol triphosphate receptor (IP3R), which was required to maintain responsivity to odors in untrained conditions. These data demonstrate that learning drives valence-correlated, compartmentalized, bidirectional potentiation and depression of synaptic neurotransmitter release, which rely on distinct mechanisms and are distributed across axonal compartments in a learning circuit.