Additional file 2: Figure S2. of Apontic regulates somatic stem cell numbers in Drosophila testes

Reduction of apt results in an increase of somatic cells in the testis and excessive cell migration in the ovary. A-B) Single optical sections of testes from males of specified genotypes stained with antibodies specific for the germline marker Vasa (magenta), the somatic marker Tj (green), and the hub marker Fas3 (green). DAPI (blue) labels DNA. Insets display stacks of optical sections of the Tj and Fas3 expression projected into 2D; a similar tissue depth was used to generate the projections for control and experimental testes. Dashed box indicates the region of the testis that is shown in the single optical section to the left. The hub is outlined in blue. Scale bars = 20 μm. A) In control testes (apt 167 /+), wild - type arrangement and numbers of somatic cells are observed: Tj + cells are adjacent to a germline cell. B) An expansion of the somatic population is observed when apt is lost: arrowhead indicates an accumulation of Tj + cells at the testis apex. C-D) Optical section images of egg chambers stained with antibodies specific for GFP or E-cadherin (green, labels anterior follicle cells and border cells or the whole epithelium, respectively) and Eya (red, labels all anterior follicle cells, except polar cells). DNA is visualized with DAPI. Anterior is to the left, scale bars = 50 μm. An anterior follicle cell (AFC) driver, c306-Gal4, is expressed in the border cell population during their specification (stage 8) through migration (stages 9-10). C) Control stage 9 egg chamber displays normal border cell specification (invasion is limited to the cluster: arrow) and migration. D) Stage 10 egg chamber: c306-Gal4; aptRNAi results in excessive invasive follicle cells (arrowheads), a phenotype that mimics the prior descriptions of apt loss of function and shows that the aptRNAi line has on-target effects. Arrow indicates the border cell cluster at the oocyte. (TIFF 4523 kb)