Drosophila Optogenetics: A Method to Manipulate Neuronal Circuits

Abstract

Source: de Vries, S. E., Clandinin, T. Optogenetic Stimulation of Escape Behavior in Drosophila melanogaster. J. Vis. Exp. (2013).

Optogenetics enables the use of light to manipulate neurons that are genetically engineered to express specific opsins–light-sensitive proteins whose light activation triggers a change in the state of the neuron. Here we describe an optogenetic approach in Drosophila using the opsin Channelrhodopsin2. The example protocol features an optogenetics assay set to study the neuronal circuitry behind the fly's escape behavior.

Protocol

This protocol is an excerpt from de Vries and Clandinin, Optogenetic Stimulation of Escape Behavior in Drosophila melanogaster, J. Vis. Exp. (2013). 1. Generate Channelrhodopsin Flies Cross UAS-ChR2 flies with the Gal4 driver of your choosing, we use G105-Gal4, which is expressed in Foma-1 neurons in the optic lobe. To eliminate the possibility of a visual response to the blue light stimulation, both fly lines are in a …

Representative Results

Figure 1: Experimental set-up showing the platform with the vertical holder and the four coolant hosing arms holding heat sinks with LED arrays affixed to them. (A) The set-up under ambient illumination. (B) The set-up when the LEDs are illuminated. (C) A close up view of a Tri-Star LED on the heat sink. (D) A close up of the Tri-Star with the tri-le…

Materials

Reagent
All-trans Retinal	Advance Scientific Chemical Inc	R3041
Equipment
Heat Sink 9.2 C/W	Luxeonstar	LPD30-30B	30 mm square X 30 mm high
Carclo 18° Tri-Lens	Luxeonstar	10507
Blue Rebel LED on Tri-Star Base	Luxeonstar	MR-B0030-20T	470 nm, 174 lm @ 700 mA.
700 mA BuckPuck DC Driver	Luxeonstar	3021-D-E-700
Wiring Harness for BuckPuck Driver	Luxeonstar	3021-HE
Pre-cut thermal adhesive tape	Luxeonstar	LXT-S-12	20 mm Hex Base
Snap-Loc Coolant Hose, ¼" ID	McMaster-Carr	5307K49
Snap-Loc Coolant Hose Connector	McMaster-Carr	5307K39	¼" NPT Male
Laboratory Grade Switching Mode Programmable DC Power Supply	BK Precision	1698
Exilim camera	Casio	EX-FH20