Syx5EP2313 homozygotes exhibit small and irregularly shaped rhabdomeres, and the photoreceptor cells show an accumulation of ER and lipid droplets, as compared to controls.
Expression via Scer\GAL4fkh.PH results in a weakly penetrant 'degenerating glands' phenotype in the embryonic salivary gland.
Syx5EP2313/Syx5AR113 mutant males (with no Scer\GAL4 driver) have no motile sperm and appear to be defective in spermatid elongation. Mutant testes contain predominantly large, oval cysts and a few elongated bundles. Mutant testes also have abnormally large mitochondrial derivatives that are associated with multiple nuclei, indicative of a failure in cytokinesis. Mutant testes also exhibit an accumulation of unusual ovoid spermatid cysts.
Syx5EP2313/Syx5AE48 is partially rescued by Scer\GAL4da.G32, Syx5EP2313
Scer\GAL4da.G32, Syx5EP2313 partially rescues Syx5EP2313/Syx5AE48
The addition of Scer\GAL4da.G32 to Syx5EP2313/Syx5AR113 animals rescues the semilethality, mostly rescues the cytokinesis phenotype and the bundle elongation defects, but no motile sperm are seen, and males remain sterile.
Syx5EP2313 is homozygous lethal, but this lethality is likely to be due to second site mutations or the effect of the P{EP} element on adjacent genes, as it is only semilethal in combination with Syx5AR113. Driving Syx5EP2313 with Scer\GAL4da.G32 cannot rescue the lethality, also suggesting second site mutations.