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Eno, S.

Publications and source records attributed to Eno, S..

2 recordsLinked to original sources

Synapse profiling of identified neurons in the Drosophila brain

Characterization of intracellular synapse heterogeneity aides to understand the intricate computational logic of neuronal circuits. Despite recent advances in connectomics, the spatial patterns of synapses and their inter-individual variability remain largely unknown. Using directed split-GFP reconstitution, we achieved visualization of endogenous Bruchpilot (Brp), a presynaptic active zone (AZ) scaffold protein, in a cell-type-specific manner. By developing a high-throughput quantification pipeline, we profiled AZ structures in identified neurons of the mushroom body circuit, where intracellular synaptic patterns are crucial due to compartmentalized connectivity. Quantitative characterization of the pattern of Brp clusters across multiple individuals revealed cell-type-dependent synapse heterogeneity and stereotypy. Furthermore, we discovered previously unidentified sub-compartmental synapse configuration and its transient structural plasticity triggered by associative learning. These profiles thus uncovered multi-layered spatial configurations of AZs, from stereotyped overall AZ distribution patterns, to local arrangements of neighboring synapses.

neuroscience↗

Octopamine signals coordinate the spatial pattern of presynaptic machineries in the Drosophila mushroom bodies

Neurons need to adjust synaptic output according to the targets. However, the target-specific synaptic structures within individual neurons in the central nervous system remains unresolved. Applying the CRISPR/Cas9-mediated split-GFP tagging, we visualized the endogenous active zone scaffold protein, Bruchpilot (Brp), in specific cells. This technology enabled the spatial characterization of presynaptic machineries only within the Kenyon cells (KCs) of the Drosophila mushroom bodies. We found the patterned accumulation of Brp among the compartments of axon terminals, where a KC synapses onto different postsynaptic neurons. Mechanistically, the localized octopaminergic modulation along {gamma} KC terminals regulate this compartmental Brp heterogeneity via Oct{beta}2R and cAMP signaling. We further found that acute food deprivation reorganizes this spatial pattern in an octopamine-dependent manner. Such coordinated regulation of local synaptic machineries thus explains how the mushroom bodies integrate changing physiological states. This subcellular information processing represents an elegant solution to expand computational capacity of the circuit.

neuroscience↗