DCX-EMAP is required for the ultrastructure of the MOs but not the TBs. (A) Representative ET slices images of the outer segment of haltere and leg receptors in wild type (left panels) and DCX-EMAP^KO (right panels). Scale bar, 200 nm. Also see Videos 1, 2, 5, and 7. (B) Statistical quantification of microtubule density in the MO and TB of haltere and leg receptors in wild type (n = 3 cells) and DCX-EMAP^KO (n = 3 cells). (C) Representative confocal images showing GFP-tubulin signal in the haltere (top view) and leg receptors (lateral view) in wild type (DCX-EMAP-gal4,uas-cd4-tdtom/uas-gfp-αTub84B) and DCX-EMAP^KO (DCX-EMAP-gal4,uas-cd4-tdtom/uas-gfp-αTub84B; DCX-EMAP^KO). The white arrowhead indicated the distal region of the outer segment in the leg receptors. Scale bar, 10 µm. (D) Statistical quantification of GFP-tubulin signal in the MOs of haltere receptors (wild type: n = 9 halteres; DCX-EMAP^KO: n = 9 halteres) and in the entire outer segment of leg receptors (wild type: n = 17 cells; DCX-EMAP^KO: n = 25 cells). (E) Representative confocal images showing Patronin-RFP signal in the haltere (top view) and leg receptors (lateral view) of wild type (Patronin-RFP^KI) and DCX-EMAP^KO (Patronin-RFP^KI; DCX-EMAP^KO). The white arrowheads indicate the position of the MOs. Scale bar, 10 µm. (F) Statistical quantification of Patronin-RFP signal in the MOs of haltere (wild type: n = 6 halteres; DCX-EMAP^KO: n = 6 halteres) and leg receptors (wild type: n = 14 cells; DCX-EMAP^KO: n = 8 cells). (G) Representative confocal images showing NompC-GFP signal in the haltere (top view) and leg receptors (lateral view) in wild type (nompC-GFP^KI) and DCX-EMAP^KO (nompC-GFP^KI; DCX-EMAP^KO). The white arrowheads indicate the MO region. Scale bar, 10 µm. (H) Statistical quantification of NompC-GFP signal in the MOs of haltere (wild type: n = 6 halteres; DCX-EMAP^KO: n = 6 halteres) and leg receptors (wild type: n = 10 cells; DCX-EMAP^KO: n = 6 cells). In panels B, D, F, and H, data are presented as mean ± SD with scattered data points. Two-sided unpaired Student’s t test. **, P < 0.01; ***, P < 0.001; n.s., no significance.