Replication Data for Ionotropic Receptor-dependent cool cells control the transition of temperature preference in Drosophila larvae

Temperature sensation guides animals to avoid temperature extremes and to seek their opti-mal temperatures. The larval stage of Drosophila development has a dramatic effect on tem-perature preference. While early-stage Drosophila larvae pursue a warm temperature, late-stage larvae seek a significantly lower temperature. Previous studies suggest that this transi-tion depends on multiple rhodopsins at the late larval stage. Here, we show that early-stage larvae, in which dorsal organ cool cells (DOCCs) are functionally blocked, exhibit similar cool preference to that of wild type late-stage larvae. The molecular thermoreceptors in DOCCs are formed by three members of the Ionotropic Receptor (IR) family, IR21a, IR93a, and IR25a. Ear-ly-stage larvae of each Ir mutant pursue a cool temperature, similar to that of wild type late-stage larvae. At the late larval stage, DOCCs express decreased IR proteins and exhibit reduced cool responses. Importantly, late-stage larvae that overexpress IR21a, IR93a, and IR25a in DOCCs exhibit similar warm preference to that of wild type early-stage larvae. These data sug-gest that IR21a, IR93a, and IR25a in DOCCs navigate early-stage larvae to avoid cool tempera-tures and the reduction of these IR proteins in DOCCs results in animals remaining in cool re-gions during the late larval stage. Together with previous studies, we conclude that multiple temperature-sensing systems are regulated for the transition of temperature preference in fruit fly larvae.