Mastodawn

Ron Tanimoto's lab characterizes synaptic diversity in the center for learning and memory in the #Drosophila brain, the mushroom bodies, using light microscopy techniques to label Bruchpilot (Brp), a presynaptic scaffold protein.

#neuroscience #synapse #MushroomBody

Albert Cardona Feb 3, 2025

Synapses in the fly brain learning and memory centre, the mushroom body:

"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 regulation by cAMP signaling."

From:
"High-throughput synapse profiling reveals cell-type-specific spatial configurations in the fly brain", by Wu et al. (Tanimoto lab) 2025
https://www.biorxiv.org/content/10.1101/2024.12.02.626511v4

#neuroscience #Drosophila #MushroomBody #synapses

High-throughput synapse profiling reveals cell-type-specific spatial configurations in the fly 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) proteins, the presynaptic active zone (AZ) scaffold, 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 pattern is crucial due to its 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 regulation by cAMP signaling. These results of synapse profiling uncovered multi-layered organizations of AZs, ranging from neighboring synapses to consistent patterns across individuals. Teaser High-throughput profiling of single active zones revealed previously unidentified multi-layered synaptic organizations. ### Competing Interest Statement The authors have declared no competing interest.

bioRxiv

PLOS Biology Jan 29, 2025

What is the role of #epigenetic mechanisms in long-lived post-mitotic #neurons? This study shows that the histone methyltransferase Trithorax regulates the metabolic state of #MushroomBody neurons and is necessary for long term #memory formation in #Drosophila #plosbiology https://plos.io/3PWaksa

Trithorax regulates long-term memory in Drosophila through epigenetic maintenance of mushroom body metabolic state and translation capacity

Epigenetic mechanisms govern cell fate decisions during cell division but what is their role in long-lived post-mitotic neurons? This study shows that the Trithorax histone methyltransferase regulates the metabolic state of mushroom body neurons and is necessary for long term memory formation in Drosophila.

Albert Cardona Jan 8, 2025

"Driver lines for studying associative learning in Drosophila" by Shuai, Sammons et al. 2024 (Yoshi Aso's lab).
https://elifesciences.org/reviewed-preprints/94168

#Drosophila #MushroomBody #LearningAndMemory #neuroscience

Driver lines for studying associative learning in Drosophila

Albert Cardona Jun 19, 2023

"Flexible specificity of memory in Drosophila depends on a comparison between choices", by Modi et al. 2023 (Glenn Turner's lab) https://elifesciences.org/articles/80923

"A memory too specific will be useless in even a slightly different environment, while an overly general memory may lead to suboptimal choices."

"Rather than forming memories that strike a balance between specificity and generality, Drosophila can flexibly categorize a given stimulus into different groups depending on the options available."

#neuroscience #LearningAndMemory #MushroomBody #Drosophila

Flexible specificity of memory in Drosophila depends on a comparison between choices

eLife

Albert Cardona May 18, 2023

"Hacking brain development to test models of sensory coding"
Ahmed et al. 2023 (Clowney lab)

"we develop methods to increase and decrease Kenyon cell claw number and therefore the number of olfactory inputs that individual Kenyon cells receive."

(claws are the inputs from projection neurons (PNs), and Kenyon cells are like granular cells in the cerebellum.)

"We then use these circuit-hacked animals to test the effects of altering Kenyon cell number and claw number on sensory representations and associative learning behavior. We find that changing Kenyon cell number only modestly affects population-level odor responses. In contrast, Kenyon cell odor responses change bidirectionally as we change Kenyon cell dendritic claw number, such that Kenyon cells become less odor-selective as their input number grows."

"Remarkably, animals with reduced Kenyon cell population size can learn simple olfactory associations, and animals with augmented sets of Kenyon cells show improved associative learning."

#Drosophila #neuroscience #KenyonCells #MushroomBody