Whole-cell recordings from Drosophila melanogaster photoreceptors enable the measurement of spontaneous dark bumps, quantum bumps, macroscopic responses to light, and current-voltage relationships under various conditions. In combination with D. melanogaster genetic manipulation tools, this method enables the study of the ubiquitous inositol-lipid signaling pathway and its target, the TRP channel.
Total time
~4–6 hours per fly (dissection, cell isolation, and recording session)
Model organism
Drosophila melanogaster
Steps
1
Dissect retina and isolate ommatidia
Remove and dissect Drosophila retina under microscopy, then enzymatically and mechanically isolate individual ommatidia for cell access. Prepare cells in culture medium for whole-cell recording.
▶ 01:01
2
Perform whole-cell voltage clamp recording
Position isolated photoreceptor cell under the patch-clamp microscope, form a gigaohm seal, and break through the cell membrane to establish whole-cell configuration. Record ionic currents under voltage control.
▶ 05:32
3
Measure single photon and light-evoked responses
Deliver calibrated light stimuli to trigger quantum bumps (single-photon events) and macroscopic responses, recording the resulting current changes to characterize photoreceptor signaling kinetics in wild-type and mutant strains.
▶ 08:21