Expression of bam^EP667 under the control of Scer\GAL4^{nos.UTR.T:Hsim\VP16} (the animals are initially raised at 18^oC and are then shifted to 29^oC after 7 days) results in a complete loss of early germ cells (stem cells, gonialblasts and spermatogonia) in the testis. This defect is seen in at least 50% of testes examined. Analysis of testes in males in which bam^EP667 is expressed under the control of Scer\GAL4^{nos.UTR.T:Hsim\VP16} (the animals are initially raised at 18^oC and are then shifted to 29^oC after 10 days) suggests that on expression of bam, early male germ cells first arrest in differentiation, accumulate as single cells and then die. At 1 day after the shift to 29^oC, the testes of males expressing bam^EP667 under the control of Scer\GAL4^{nos.UTR.T:Hsim\VP16} are indistinguishable from those of control males. By 2 days after the temperature shift, the testes of mutant animals contain at the apical tip an increased number of cells with a balloon shaped spectrosome (characteristic of male germline stem cells and gonialblasts) compared to controls. Many of the testes with increased numbers of spectrosomes have either no or only a few small fusomes (1-5 compared to more than 10 in wild-type testes). By 3-5 days after the temperature shift, early germ cells in many of the mutant testes are dying. By 10 days after the temperature shift, the majority of mutant testes lack all early stage germ cells. In addition, the mutant testes show a massive increase in size of the somatic hub, in many cases the hub is enlarged up to 20 times compared to the hub in control testes. This increase in hub size is generally seen several says after the temperature shift (at 2 days after the shift the hub is only slightly enlarged).

Strong bam allele.

bam^EP667/bam[+] is a suppressor of ovary phenotype of nanos¹⁸/Df(3R)nanos

bam^EP667/bam[+] is a suppressor of germline stem cell phenotype of nanos¹⁸/Df(3R)nanos

bam^EP667/bam[+] is a suppressor of ovary phenotype of nanos⁵³/Df(3R)nanos

bam^EP667/bam[+] is a suppressor of germline stem cell phenotype of nanos⁵³/Df(3R)nanos