Digital scanning lightsheet microscopy (DSLM) for Drosophila whole brain functional imaging

Intravital imaging has presented a powerful tool for tracking cellular function and structural dynamics in the real environment of a complex multicellular organism. However, most commercial microscopy systems are limited by optical design, allowing only long-term live imaging of transparent samples, such as Drosophila embryo, zebrafish embryo, and suffering from slow image acquisition speeds. Consequently, they can only generate two-dimensional time-lapse images at selected optical planes. Here, we introduce a high-resolution Bessel beam based vertical digital scanning light sheet microscopy (V-SPIM) for real-time imaging of the adult fruit fly brain. Compared to traditional multiphoton imaging or multi-point confocal microscopy, Bessel beam based light sheet microscope exhibits lower photodamage and faster acquisition volume rates (V.R.) higher than 1Hz (with proper exposure time (E.T.) and signal to background ratio (SNR)) for each volume(330×330×162𝜇𝑚), allowing us to perform long-term volumetric time-lapse functional imaging in adult animals. This novel approach allows us to visualize the olfactory coding of various odors in a multitude of cells within a single fly brain.