Fig. 1

Schematic of the experimental set up for optogenetic muscle contraction (OMC). A Schematic of the optogenetic set up used to induce muscle contractions in Drosophila larvae. TOP: Circuit diagram of all the components involved in regulating the light emitting diodes (LEDs). The circuit components allow rapid switching of the high-power LEDs using a microprocessor controller such as an Arduino board. (BOTTOM) Schematic of the heat sink, to which the LEDs were attached, and the attached assembly used as a holder for the larval vials. Holders were assembled from laser-cut acrylic pieces and are designed to prevent light leak between tubes while allowing air flow to support oxygen supply. B Schematic of a basic experimental set up for inducing optogenetic contractions in third instar larvae. The images show snapshots of larvae over-expressing CsChrimson in their motor-neurons (OK6-Gal4 > CsChrim) when the LEDs were either OFF or ON, demonstrating the synchronized contraction of the larval body wall muscles (see Video 1 for the larval OMC). L1 and L3 correspond to first and third larval instar stages, respectively, and ATR is all-trans retinal