Fig. 5.

Specific TRP mutants show defective antennal nerve responses to rotation. (A) Schematic of the recording apparatus. The recording electrode and fly were both mounted on a rotatable platform. Rotation of the platform changes the orientation of the fly body, but the electrode position remains constant relative to the fly. The recording electrode was positioned between the first and second antennal segment where axons of Johnston's organ fasciculate (Inset). (B–D) Bidirectional 90° pitch (B), roll (C), and yaw (D) all induced transient spiking responses in the antennal nerve of Canton-S (CS) wild-type flies. The response was reproducible with repetitive stimulations. Expanded trace in B shows quantification of the response. We counted the number of spikes with amplitudes greater than 2-fold baseline activity. The threshold is represented with the horizontal line in cyan. The counted spikes are marked with blue dots at their negative peaks and represented by a temporally aligned raster above the trace. Variability in the amplitude of individual spikes suggests that multiple units (neurons) were recorded. (E) Spiking responses to bidirectional 90° pitches were abolished by gluing the third antennal segment to the head to prevent its movement, and the response partially recovered after removing the glue. (F) Sample traces for nan^36a, iav³⁶²¹, pain¹, pain^Gal4, and pyx³ mutants in response to bidirectional 90° pitches. Each trace represents an example that had a spike number (forward pitch) at the median for all specimens of that genotype. (G) Quantification of spiking responses in the mutants. For nan^36a, iav³⁶²¹, and pain^Gal4. *, significant difference from CS by ANOVA (α level = 0.05) and post hoc test of Games-Howell. *, P < 0.05 by unpaired t test for pyx³. The number (n) of antennae recorded in each group is shown. Data are mean ± SEM.