Fig. 1.

The tracheal dorsal trunk (DT) and salivary ducts of dmt^I184/aul (=dmt³⁹⁹⁹) mutants have frequent gaps. A–C: Tracheal morphogenesis in wild-type embryos is shown. Arrowheads indicate tracheal metamere 4. Inset in middle panel shows different tracheal branches. D–F: Duct morphogenesis in wild-type embryos. Arrows indicate regions where tubes are still closing. G–N: dmt^I184/aul³⁹⁹⁹ mutant trachea and salivary duct have large gaps. Arrowheads indicate gaps in tracheal DT lumena, asterisks indicate shortened tracheal branches and arrows indicate where gaps are present in dmt/aul mutant salivary ducts. All embryos are oriented with anterior to the left. Tracheae are shown in lateral views, salivary ducts in ventral views. O: Tracheal DT and salivary duct phenotypes were quantified either as severe (multiple and/or large gaps), moderate (single small gaps), or no gaps. P: aul mutations were shown to be allelic to dmt through a series of complementation crosses using deficiencies and existing dmt alleles (see also Table 1) and recombination mapping using two nearby P-element insertions, P1 and P2, marked with white⁺.