Visualization of axonal protein allocation in Drosophila with whole brain localization microscopy

Chu, L.-A.; Lu, C.-H.; Yang, S.-M.; Feng, K.-L.; Liu, Y.-T.; Chen, C.-C.; Tsai, Y.-C.; Chen, P.; Lee, T.-K.; Hwu, Y.-K.; Chen, B.-C.; Chiang, A.-S.

doi:10.1101/454942

bioRxiv · 10.1101/454942

Visualization of axonal protein allocation in Drosophila with whole brain localization microscopy

Chu, L.-A.·Lu, C.-H.·Yang, S.-M.·Feng, K.-L.·Liu, Y.-T.·Chen, C.-C.·Tsai, Y.-C.·Chen, P.·Lee, T.-K.·Hwu, Y.-K.·Chen, B.-C.·Chiang, A.-S.

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Abstract

Long-term memory (LTM) formation requires learning-induced protein synthesis in specific neurons and synapses within a neural circuit. Precisely how neural activity allocates new proteins to specific synaptic ensembles, however, remains unknown. We developed a deep-tissue super-resolution imaging tool suitable for single-molecule localization in intact adult Drosophila brain, and focused on the axonal protein allocation in mushroom body (MB), a central neuronal structure involved in olfactory memory formation. We found that insufficient training suppresses LTM formation by inducing the synthesis of vesicular monoamine transporter (VMAT) proteins within a dorsal paired medial (DPM) neuron, which innervates all axonal lobes of the MB. Surprisingly, using our localization microscopy, we found that these learning-induced proteins are distributed only in a subset of DPM axons in specific sectors along the MB lobes. This neural architecture suggests that sector-specific modulation of neural activity from MB neurons gates consolidation of early transient memory into LTM.

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Chu, L.-A., Lu, C.-H., Yang, S.-M., Feng, K.-L., Liu, Y.-T., Chen, C.-C., Tsai, Y.-C., Chen, P., Lee, T.-K., Hwu, Y.-K., Chen, B.-C., Chiang, A.-S.. 2018-10-27. Visualization of axonal protein allocation in Drosophila with whole brain localization microscopy. https://doi.org/10.1101/454942

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