Insertion in the 5' untranslated region.
A fluorescent 10kD dye injected into the body cavity readily leaks into the lumens of the trachea and salivary gland in mutant embryos, indicating a loss of paracellular barrier function. In addition, the fluorescent 10kD dye penetrates into the nerve cord of mutant embryos, indicating a defect in the blood-brain barrier.
The length of the dorsal trunk of stage 16 homozygous and kuneC309/Df(2R)BSC696 embryos is significantly increased compared to controls, and the mutant dorsal trunks appear tortuous. Mutant trachea have a diffuse, disorganized lumenal matrix (in contrast to wild-type trachea which contain a dense, fibrillar chitin cable) and lack the gap between the chitin cable and the apical surface of the cells that is seen in wild-type trachea.
kuneC309 is rescued by kuneUAS.cNa/Scer\GAL4da.G32
At 23[o]C, expression of kuneScer\UAS.cNa under the control of Scer\GAL4da.G32 only partially rescues the septate junction defects of kuneC309 mutants and does not rescue their embryonic lethality. At 28[o]C, expression of kuneScer\UAS.cNa under the control of Scer\GAL4da.G32 rescues both the septate junction defects and embryonic lethality of kuneC309 mutants.