Imaging through the Whole Brain of Drosophila at λ/20 Super-resolution

• Published in: iScience Vol. 14; pp. 164 - 170
• Main Authors: Lin, Han-Yuan, Chu, Li-An, Yang, Hsuan, Hsu, Kuo-Jen, Lin, Yen-Yin, Lin, Keng-Hui, Chu, Shi-Wei, Chiang, Ann-Shyn
• Format: Journal Article
• Language: English
• Published: United States Elsevier 26.04.2019
• Subjects: Techniques in Neuroscience; Optical Imaging; Neuroscience
• ISSN: 2589-0042; 2589-0042
• DOI: 10.1016/j.isci.2019.03.025

Recently, many super-resolution technologies have been demonstrated, significantly affecting biological studies by observation of cellular structures down to nanometer precision. However, current super-resolution techniques mostly rely on wavefront engineering or wide-field imaging of signal blinking or fluctuation, and thus imaging depths are limited due to tissue scattering or aberration. Here we present a technique that is capable of imaging through an intact Drosophila brain with 20-nm lateral resolution at ∼200 μm depth. The spatial resolution is provided by molecular localization of a photoconvertible fluorescent protein Kaede, whose red form is found to exhibit blinking state. The deep-tissue observation is enabled by optical sectioning of spinning disk microscopy, as well as reduced scattering from optical clearing. Together these techniques are readily available for many biologists, providing three-dimensional resolution of densely entangled dendritic fibers in a complete Drosophila brain. The method paves the way toward whole-brain neural network studies and is applicable to other high-resolution bioimaging.