Gef263/Gef263 is semi-lethal. Escapers have small, rough eyes and abnormal wings.
The number of male germline stem cells is dramatically reduced in the testes of Gef263/Gef264 animals compared to wild-type. The hub is not lost, but expression of some marker genes in the hub is. The number of cyst progenitor cells is also reduced in these testes.
The testes of Gef263/Gef26k13720 animals have normal numbers of germline stem cells.
Gef263 homozygous germline stem cell clones develop normally.
During larval stages, male germline stem cells in Gef263/Gef264 animals become detached from the hub. Marker localisation data suggests that the adherens junctions between the hub cells and the surrounding stem cells are impaired.