esg05729/esg35Ce-1 pharate pupae have well-differentiated testes. The stem cells and spermatogenic cells that are normally found at the tip of the testis are missing in the mutants, with the mutant testes containing only sperm bundles and motile sperm.
Heterozygotes with esg35Ce-3 survive to the pharate adult stage, larval abdominal histoblasts undergo endoreplication and become polyploid preventing the development of the adult abdominal epidermis.
Many heteroallelic combinations studied. Where flies die as pharate adults sternite/tergites are partially or completely deleted. Where flies are viable, they have held out wings, and may have sternite/tergites partially deleted and be sickly. Abdominal histoblasts were examined in heteroallelic combinations and found to have nuclei 3.4 times larger (revealed by Ecol\lacZ expression from esg05729 allele) and with 7-16 times as much DNA (DAPI fluorescence) as wild type histoblast nuclei. esg05729/esg35Ce-3 larvae abnormally replicate the DNA of histoblasts (BrdU incorporation). Furthermore, haematoxylin staining revealed that proliferation of histoblasts does not occur during metamorphosis of esg05729/esg35Ce-3 flies. Humeral discs in esg05729/esg35Ce-3 flies have nuclei similar in size to wild type, and differentiate normal dorsal T1 structures.