Figure 2. Pupation height selection is influenced by function of the mdIV nociceptor neurons.

(A) Temperature shift protocol for stage-specific inactivation of mdIV nociceptors. Temporally staged larval collections(4 hr) were grown at 25°C throughout embryonic and larval foraging stages to maintain wild-type mdIV activity. At 96 h AEL, just as larvae are beginning wandering stage and food exit, cultures were shifted to 29°C to inactivate either Shi[ts1] or GAL80^ts respectively resulting in selective mdIV nociceptor inactivation during wandering stage. (B) mdIV nociceptor inactivation in ppk1GAL4/UAS-shi[ts1] larvae resulted in a significantly increased overall pupation height reflected as an upward deflection of the Pupation Height Index. Larval culture at 23°C to maintain Shi[ts1] function throughout pupation caused a higher overall PHI due to the lower temperature but resulted in no significant difference in PHI between control(UAS-shi[ts1]/+) and ppk1-GAL4/UAS-shi[ts1] larvae. (C) Electrical silencing of mdIV nociceptors in tubPGAL80^ts/+; ppk1GAL4/UAS- dOrk1ΔC larvae also caused a shift to higher overall pupation height. Expression of dOrk1ΔNC, expressing an inactivated channel isoform, showed no significant difference in PHI from controls. (D) mdIV nociceptor inactivation in clh24-GAL4/UAS-shi[ts1] larvae resulted in the same significant upward deflection of the Pupation Height Index. The clh24-GAL4 transposon is an independent GAL4 driver expressed specifically in the mdIV nociceptors similar to ppk1-GAL4. Error bars represent SEM with n≥15 for all values. ***P<.0001, one-way ANOVA with Tukey posttest.