The auxin-inducible degradation system enables conditional PERIOD protein depletion in the nervous system of Drosophila melanogaster.

Tools that allow inducible and reversible depletion of target proteins are critical for biological studies. The plant-derived auxin-inducible degradation system (AID) enables the degradation of target proteins tagged with the AID motif. This system has been recently employed in mammalian cells as well as in Caenorhabditis elegans and Drosophila. To test the utility of the AID approach in the nervous system, we used circadian locomotor rhythms as a model and applied the AID method to temporally and spatially degrade PERIOD (PER), a critical pacemaker protein in Drosophila. We found that the period locus can be efficiently tagged with the AID motif by CRISPR/Cas9-based genome editing without disrupting PER function. Moreover, we demonstrated that the AID system could be used to induce rapid and efficient protein degradation in the nervous system as shown by effects on circadian and sleep behaviors. Furthermore, the protein degradation by AID was rapidly reversible after auxin removal. Together, our results show that the AID system provides a powerful tool for behavior studies in Drosophila.