“An eye in an eye”: tangential section through the fly visual system showing glial processes (green) and nuclei (blue), and rows of photoreceptor axons (red).

Iris Salecker : Tools to dissect visual circuit assembly

Introduction

Tools to help target areas in the Neuron.

Figure 1: In the adult visual system, R1-R8 photoreceptor neurons (blue) extend axons from the retina into the lamina and medulla. Neurons in the target area were labeled with the Flybow 2.0 approach.

To facilitate the identification and functional analysis of neuronal and glial subtypes with single cell resolution, we have recently generated three Drosophila variants of the mouse Brainbow-2 system (Livet et al., 2007), called Flybow (FB).

This approach enables us to label cells in different colors in the same sample.

It relies on the stochastic expression of membrane-tethered fluorescent proteins by excision and inversion of opposing coding sequences arranged within cassettes. FB combines the Gal4/UAS system and a modified FLP/FRT system with altered specificity to provide (1) precise spatio-temporal control of expression in any genetically accessible cell population and (2) compatibility with available FLP/FRT-system based genetic approaches for functional studies. Our current efforts aim at developing this approach further by adding new sets of FB transgenes to our toolbox.