Fig. 1. Antennal defects in amos mutants. Third antennal segments are shown. (A) Wild-type antenna, with trichodea indicated (t). (B) Higher power view with examples marked of sensilla coeloconica (c), basiconica (b) and trichodea (t). (C) amos¹/Df(2L)M36-S6. Third segment is reduced because of missing basiconica and trichodea. Ectopic mechanosensory bristles are indicated (br). (D) Higher power view showing an abnormal domed sensillum (arrow) and a normal sensillum coeloconicum (arrowhead). Sensilla are very sparse. (E) amos² with numerous abnormal sensilla (arrows). (F) Double mutant for amos and ato (clone of amos¹ tissue in ato¹ fly: eyFLP; FRT-amos¹/FRT-nlsGFP; ato¹). The clone patch contains no sense organs except bristles. (G) Double mutant for amos and sc^10-1 (which removes both ac and sc function). The extra bristles of amos¹ are largely dependent on ac/sc function. (H) Double mutant for amos and lz. The extra bristles of amos¹ are absent and therefore depend on lz function.