Figure 5. Intermediate sensilla.
(A) SBEM images of representative intermediate, basiconic, and trichoid sensilla sampled from the same data set. Intermediate sensilla display higher luminal density than the other two sensillum types. Arrows: basal drum; s.b. small basiconic; and t.b. thin basiconic. (B) 3D model and SBEM images of a representative ai2 sensillum. ORNs are pseudocolored to indicate neuronal identity: ai2A (blue) and ai2B (orange). Dashed lines indicate positions of the corresponding SBEM images. Th: thecogen; Tr: trichogen; and To: tormogen. (C) 3D models for individual ai2 neurons as shown in (B). Filled arrow heads: ciliary constriction; empty arrow heads: sensillum base position. (D) Volumes of the soma, inner, and outer dendrites of compartmentalized ai2 neurons. Lines connect data points from neurons housed in the same sensillum, mean± s.e.m. n=3. Significant differences (p<0.05) are indicated by different letters; paired t-test for comparison between neighboring neurons. (E–G) As in (B–D), except that images are shown for a representative ai3 sensillum. ORNs are pseudocolored to indicate neuronal identity: ai3A (blue), ai3B (orange), and ai3C (yellow). n=2. Scale bars: 2 μm for 3D models and 1 μm for SBEM images. The scale bar in the first image panel also pertains to other images unless indicated otherwise. ORN, olfactory receptor neuron; SBEM, serial block-face scanning electron microscopy.