More than half of the eggs laid at 18Â°C by females heterozygous for orbF343 have ventralized egg shells.
85% of embryos derived from heterozygous female hatch.
100% of eggs laid by orb7D4-11/orbF343 or orbmel/orbF343 females are ventralised and unfertilised. 90% of eggs laid by orb7D1-16/orbF343 females are ventralised and unfertilised. The remaining eggs give rise to embryos with abdominal defects. Egg chambers of orb9D6-3/orbF343 females arrest early during oogenesis and fail to reach vitellogenic stages. 90% of egg chambers of orb7E4-5/orbF343 females arrest early during oogenesis and fail to reach vitellogenic stages. Eggs that are laid are ventralised and unfertilised.
0% of eggs derived from orbmel/orbF343 females have wild-type dorsal appendages, 3.4% have fused dorsal appendages and 96.6% have no dorsal appendages. The eggs do not hatch.
16-cell cysts do not form in orbF343 ovaries.
The female germline cyst fails to go through the last mitotic division and contains only eight cells. All of the cells in region 2a seem to form a complete synaptonemal complex (SC). Most mutant cysts degenerate in region 2, but clusters of cells are occasionally seen in region 3, which are presumably single cysts that have not degenerated, as they always contain 8 cells. In these cases, all 8 nuclei show strong SC staining reminiscent of the pachytene stage.
Oogenesis is arrested at or just before the formation of the 16-cell cyst in mutant ovaries.
Degenerating cysts. Some heterozygous orbmel/orbF343 embryos display absence of dorsal appendages, oocytes are small than normal and surrounded by columnar follicle cells and eggs are also smaller than normal. orbF343 interacts genetically with Egfr and grk, double heterozygote embryos display fused dorsal appendages.
Oogenesis has blocked during a stage of cyst development, the ovaries are very small and consist of germarium like structures populated by many small undifferentiated cells.
orbmel/orbF343 causes lateralization. Eggs are shortened and rounded posteriorly like dorsalized eggs but like ventralized eggs their dorsal appendages are fused dorsally, in 49% of eggs, or absent, in 46% of the eggs. 37% of the eggs contain embryos.