203bp deletion in the first coding exon (starting at C420 in the coding sequence of the cDNA). This results in a frameshift which is predicted to truncate the protein before the ETS DNA-binding domain.
Approximate position of 203 bp deletion reported to start at C420 and extend into aop, which results in a frameshift.
Tracheal branching pattern is normal in aopO199 embryos, but local exclusions of luminal material are seen in the dorsal trunk (DT), most commonly within metameres 5-9, close to DT fusion joints. The exclusion of luminal material is due to cellular bridges traversing the lumen. After completion of DT fusion in the mutant embryos the lumen begins to bend towards one side, resulting in a local indentation. This indentation is then invaded from both sides by two fine luminal extensions, which join and give rise to a secondary lumen separated from the original one by a cellular bridge.
Mutant embryos contain extra tracheal fusion cells compared to wild type in the dorsal trunk, but not in other tracheal branches. At least four fusion cells are located adjacent to the luminal bifurcations seen in the mutant embryos. The extra fusions cells undergo morphological transformations characteristic of wild-type fusions cells, and accomplish extra fusion events. Extra cells are first detectable during tracheal branch outgrowth at stage 13.
Mutant embryos contain extra terminal cells compared to wild in the dorsal branches, visceral branches, lateral trunk and ganglionic branches, but not in the dorsal trunk. The additional cells are first detectable as the branches extend in stage 14. The additional terminal cells give rise to additional terminal ramifications.
aopO199 has tracheal fusion cell | increased number phenotype, suppressible by panΔN.UAS/Scer\GAL4btl.PS
aopO199/aopO199 is a non-suppressor of tracheal fusion cell phenotype of Scer\GAL4btl.PS, panΔN.UAS
Expression of panΔN.Scer\UAS under the control of Scer\GAL4btl.PS suppresses the formation of supernumerary tracheal fusion cells which is seen in aopO199 homozygotes, with the double mutant embryos showing a loss of fusion cells similar to that seen in single mutant panΔN.Scer\UAS; Scer\GAL4btl.PS embryos.
Most tracheal tip cells adopt the terminal cell fate in salm1 aopO199 double mutant embryos.
Expression of salmScer\UAS.cKa under the control of Scer\GAL4btl.PS in a homozygous aopO199 background results in supernumerary fusion cell formation throughout the tracheal system, and terminal cell formation is largely suppressed.
