Figure 1.

Ras^V12 overexpression induces GSC over-proliferation

(A) Schematic diagram of a germarium and an early-stage egg chamber. GSC, germline stem cell; CB, cystoblast; 2, 4, 8, 16CC, 2-, 4-, 8-, 16-cell cystocytes. The oval red cells to the left of GSCs are cap cells, and the oval blue cells to the left of cap cells are terminal filament cells. The triangular yellow cells are escort cells and inner sheath cells. The dark and light pink cells in the posterior part of the germarium are follicle stem cells and follicle cells, respectively. The two red cells in the anterior part of the egg chamber are polar cells.

(B) The activation pattern of nos-GAL4-VP16. The two red asterisks denote germline stem cells.

(C–E) Representative germarial images. α-Spectrin labels spectrosomes in GSCs/cystoblasts (spherical shape) and fusomes in cystocytes (branched shape). All images are of the same magnification.

(F) Quantification of germarial sizes. For each genotype, 30 germaria were quantified, and, for each germarium, its biggest 2D size scanned by confocal microscope in one focal plane was used to reflect its 3D size. Data represent mean ± SD, and, for each group of data, the mean number is labeled right. Statistical significance was determined by t test. ^∗∗∗: p < 0.001.

(G) Quantification of spherical spectrosomes per germarium. For each genotype, 30 germaria were quantified.

(H–K′) Representative germarial images. The red asterisks in (H and I) denote cap cells, and the pMad⁺ germ cells to the right of them are GSCs. All images are of the same magnification. These experiments were performed at 29°C, and 7-day-old flies were used. See all genotypes in Table S1 and the raw quantification data in Table S2. See also Figures S1 and S2.