Single-Objective Light-Sheet Microscopy Allows Long-Term, High-Resolution In Vivo Brain Imaging of Drosophila

However, in the fruit fly, its implementation has been hindered by a trade-off among spatial resolution, speed, photobleaching, phototoxicity, and setup complexity required to access specific target regions of the small brain of Drosophila. Here, we present DrosoScope: a single-objective light-sheet microscope customized for <i>in vivo</i> imaging of adult flies and optimized for maximum resolution.

With it, we imaged the axonal projections of small lateral ventral neurons (s-LNvs) in intact adult flies. We imaged the plasma membrane, cytoplasm, mitochondria, and dense-core vesicles with high spatial resolution of up to 310 nm, lower photobleaching than confocal microscopy, lower invasiveness and reduced sample-mounting complexity than alternative light-sheet technologies, and without relying on potentially phototoxic pulsed infrared lasers.