Mc1500

ERGs were recorded as previously described^{25 (link)}. In brief, voltage measurements of immobilized female flies were recorded with electrodes containing 2 M NaCl placed on the corneal surface and inserted into the thorax. Measurements were filtered through an electrometer (IE-210; Warner Instruments), digitized with a Digidata 1440 A and MiniDigi 1B system (Molecular Devices), and recorded using Clampex 10.2 (Axon Instruments). Light pulses (1 s at 600 lux, unless otherwise noted) were computer controlled (MC1500; Schott). Five ERG recordings from at least ten flies were performed in triplicate and quantified with Clampfit software (Axon Instruments). Light intensities were measured using a Fisher Scientific Dual-Range Light Meter (Fisher scientific).

ERGs recordings were done as described previously^{21 (link)}. In brief, glass electrodes filled with 2 M NaCl were placed in the fly thorax (reference electrode) and surface of the corneal lens (recording electrode). A computer-controlled LED light source (MC1500; Schott, Mainz, Germany) was pulsed for 1 s at 4 s intervals. The traces of ERG were collected by an electrometer (IE-210; Warner Instruments, Hamden, CT), digitized with a Digidata 1440 A and MiniDigi 1B system (Molecular Devices, San Jose, CA), and recorded using Clampex 10.2 (Molecular Devices) and quantified with Clampfit software (Molecular Devices). Recordings were done in batches of ten to twelve and resulting quantification for each genotype are pooled from three independent and blinded biological replicas.

First, 0-, 7- and 14-day-old flies were fixed in one direction on glass slides using non-toxic glue. Then, 2 M NaCl (for use as a conductive medium) was used to fill both recording and reference electrodes. A reference electrode was placed in the torso of each fly and recording electrodes were put over the retina. Electrode voltage was amplified using a Digidata 1440A, filtered through a Warner IE-210, and the Clampex 10.1 software (Axon Instruments) was used for all recordings. A light stimulus was provided in 1 s pulses via a computer-controlled red LED system (Schott MC1500). All experiments were conducted in duplicate or triplicate with at least ten recordings completed for each genotype and experimental condition.