Flies bearing Cad99C^57A mutant clones in the Johnston's organ very occasionally (around 1% of cases) exhibit scolopidia detached from the hinge of the second and third antennal segment.

Most embryos from Cad99C^57A/Cad99C^120B females are not recoverable. Most (>90%) of these maternal and zygotic (M/Z)Cad99C-expressed embryos develop normally but have longer, thinner salivary glands than in wild-type; only a small subset of the recovered embryos show severe morphological defects. Embryos missing only maternal or only zygotic function do not have overt defects. No phenotypic differences are detected at the ultrastructural level in comparisons of stage 15/16 Cad99C[M/Z] mutant and wild-type salivary glands. The overall polarity of Cad99C[MZ] mutant salivary glands appear unaffected and the mutant salivary glands migrate normally, contacting the same tissues at all stages as wild-type salivary glands. Total cell numbers are not significantly different and the apical domain size and elongation ratio of individual cells is also unchanged. Indeed, the only difference is that fewer cells surround the lumen in cross-sections of the Cad99C[M/Z] mutant salivary glands compared with wild-type. Thus, the longer, thinner salivary gland lumen in Cad99C[M/Z] mutants reflect differences in cell rearrangement during tube elongation.

Eggs laid by homozygous females spontaneously collapse after deposition and do not develop into larvae. These eggs are nearly all permeable to the dye Neutral Red after dechorionation, suggesting a vitelline membrane defect. Ultrastructurally, the mutant vitelline membrane is of uneven thickness and occasionally has holes.

More than 80% of eggs laid by Cad99C^57A/Cad99C^51C and Cad99C^57A/Cad99C^120B females are permeable to the dye Neutral Red after dechorionation, suggesting a vitelline membrane defect. Ultrastructurally, the Cad99C^57A/Cad99C^51C vitelline membrane is of uneven thickness and occasionally has holes.

Homozygous follicle cells have abnormal microvilli. When analysed by electron microscopy, they are mainly oriented towards neighbouring follicle cells and are often seen in the space between the vitelline bodies and the apical follicle cell surface. This contrasts with the microvilli of wild-type follicle cells, which are mainly oriented towards the oocyte.

Cad99C^57A clones generated at the A/P boundary of the wing imaginal disc, using the FLP/FRT technique, remain entirely in the compartment in which they are generated. This is the same as for wild-type clones.

Cad99C^57A/Cad99C[+] is an enhancer of Johnston organ | P-stage | somatic clone phenotype of Ubr3^B

Cad99C^57A/Cad99C[+] is an enhancer of scolopidium | P-stage | somatic clone phenotype of Ubr3^B