Optogenetic Manipulation of Selective Neural Activity in Free-Moving Drosophila Adults

Activating selected neurons elicits specific behaviors in Drosophila adults. By combining optogenetics and laser-tracking techniques, we have recently developed an automated laser-tracking and optogenetic manipulation system (ALTOMS) for studying how brain circuits orchestrate complex behaviors. The established ALTOMS can independently target three lasers (473-nm blue laser, 593.5-nm yellow laser, and 1064-nm infrared laser) on any specified body part of two freely moving flies. Triggering light-sensitive proteins in real time, the blue laser and yellow laser can respectively activate and inhibit target neurons in artificial transgenic flies. Since infrared light is invisible to flies, we use the 1064-nm laser as an aversive stimulus in operant learning without perturbing visual inputs. Herein, we provide a detailed protocol for the construction of ALTOMS and optogenetic manipulation of target neurons in Drosophila adults during social interactions.