One copy of E2f07172 has no effect on hemocyte proliferation in third instar larvae.
E2f107172 germline stem cell (GSC) clones behave similarly to control GSC clones and do not dramatically affect GSC maintenance.
E2fi2/E2f07172 trans-heterozygotes are viable and can complete oogenesis. Eggs laid by these females display a variety of dorsoventral polarity defects, including eggshells with fused dorsal appendages (ventralised, 22%), eggshells with fused but slightly expanded dorsal appendages (between dorsalised and ventralised, 39%), and eggshells with fused but widely spread dorsal appendages (strongly dorsalised, 11%). In addition, 8% of the eggs laid by E2fi2/E2f07172 females have greatly degenerated dorsal appendages, which obscure the dorsoventral polarity pattern of these eggshells.
In E2f07172 mutants, unlike CycE mutants, no homeotic transformation of NB6-4t to NB6-4a is observed. While the number of NB6-4 derived glia in the thorax is unaffected, the number of NB6-4 derived neurons per thoracic segment is reduced from 5-6 to 2-4 in approximately 85% of embryos.
In E2fi1/E2f07172 egg chambers, unlike wild-type (where nurse cells undergo apoptosis during stages 12 to 13 and have degenerated by stage 14), a cluster of nurse cells remain attached to the stage 14 oocyte and having failed to under go apoptosis. Some mutant eggs chambers, one or a few persisting nurse cells do show signs of apoptosis, but not until stage 14.
E2f1/Dp-dependent G[]-S transcription is disrupted late in embryogenesis, but S phase takes place. Lethality occurs at late larval, early pupal stages. Lethality of E2f191/E2f107172 occurs at late larval, early pupal stages. Larval growth is dramatically delayed taking 288 to 432 hours from larvae to pupation compared to 120 hours for wild type. Five days after egg laying larvae are very sluggish and much smaller in size than wild type. Salivary glands, imaginal discs and the brain are greatly reduced in size in 5 day old larvae but they do grow to wild type proportions by the end of their larval life. Larvae also exhibit melanotic pseudotumours, they first appear 7 days after egg laying and they grow and darken as the larvae age.
Clones induced in the eye in the first or second larval instar are not detected in the adult eye. They can be detected in the eye disc, but are much smaller than the adjacent twin spots, with fewer cells. These cells have initiated neuronal differentiation. Resulting ommatidia have incomplete sets of photoreceptors, and photoreceptors that are present often have abnormal morphology. Rhabdomeres are small in diameter, the rhabdomeres of the outer photoreceptors may project centrally and the photoreceptors do not extend the full length of the retina.