Fig. 3. Major participants in GSC maintenance and differentiation in (A) female and (B) male gonads. Germ-line stem cells (GSCs) and their differentiating daughter cells (Cb, cystoblast in females and gonialblast in males) are shown in shades of green. The somatic cells of the niche (cap cells in females and hub cells in males) are colored pink. Other somatic cells [inner sheath (IS) cells in females, and somatic stem cells (SSCs) and cyst cells in males) may affect either GSCs or their differentiating daughter cells, or both, and are shown in blue. Proteins and organelles that act within each cell type are noted. Major and minor signaling pathways emanating from the niche are marked with large and small arrows, respectively.