Single Objective Light Sheet Microscopy allows high-resolution in vivo brain imaging of Drosophila.

Tassara, F. J.; Barella, M.; Simo, L.; Folgueira, M.; Rodriguez-Caron, M.; Ispizua, J. I.; Ellisman, M. H.; de la Iglesia, H. O.; Ceriani, M. F.; Gargiulo, J.

doi:10.1101/2024.11.06.622263

bioRxiv · 10.1101/2024.11.06.622263

Single Objective Light Sheet Microscopy allows high-resolution in vivo brain imaging of Drosophila.

Tassara, F. J.·Barella, M.·Simo, L.·Folgueira, M.·Rodriguez-Caron, M.·Ispizua, J. I.·Ellisman, M. H.·de la Iglesia, H. O.·Ceriani, M. F.·Gargiulo, J.

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Abstract

In vivo imaging of dynamic sub-cellular brain structures in Drosophila melanogaster is key to understanding several phenomena in neuroscience. However, its implementation has been hindered by a trade-off between spatial resolution, speed, photobleaching, phototoxicity, and setup complexity required to access the specific target regions of the small brain of Drosophila. Here, we present a single objective light-sheet microscope, customized for in vivo imaging of adult flies and optimized for maximum resolution. With it, we imaged the axonal projections of small lateral ventral neurons (known as s-LNvs) in intact adult flies. We imaged the plasma membrane, mitochondria, and dense-core vesicles with high spatial resolution up to 370 nm, ten times lower photobleaching than confocal microscopy, lower invasiveness and complexity in sample mounting than alternative light-sheet technologies, and without relying on phototoxic pulsed infrared lasers. This unique set of features paves the way for new long-term, dynamic studies in the brains of living flies.

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Tassara, F. J., Barella, M., Simo, L., Folgueira, M., Rodriguez-Caron, M., Ispizua, J. I., Ellisman, M. H., de la Iglesia, H. O., Ceriani, M. F., Gargiulo, J.. 2024-11-07. Single Objective Light Sheet Microscopy allows high-resolution in vivo brain imaging of Drosophila.. https://doi.org/10.1101/2024.11.06.622263

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