CID and CAL1 overexpression and HASPIN knockdown promote stem cell self-renewal. (A–O′) Wide-field z-stack projection of nanos-Gal4, UAS_CAL1-YFP_UAS_CID-mCherry (CID-CAL1_OE), and UAS-CAL1-YFP (CAL1_OE) germaria, stained for anti-CID and or anti-FIB (cyan). Star, terminal filament; arrows, centromeres; arrowheads, nucleolus; 3-d-old female flies. (P) Wide-field z-stack projection of nanos-Gal4 and UAS_CID-mCherry germaria stained for DAPI (cyan) and anti-CID (green). (Q) Ratio of the number of SXL-positive cells to the number of pMAD-positive cells. n.s., not significant; **, P < 0.005; ***, P < 0.0005. (R) Confocal z-stack projection bam-Gal4 and CAL1 RNAi germaria stained for DAPI (blue), anti-BAM (red) and anti-CAL1 (green). Germ cells belonging to the 16-cell cyst chamber were selected based on the VASA marker (not depicted) and the lack of BAM signal in the control and in the CAL1 RNAi. (S) Confocal z-stack projection of bam-Gal4 and CENP-C RNAi germaria, stained for DAPI (blue), anti-BAM (red), and anti-CENP-C (yellow). Star, terminal filament; white dotted line in R and S, the end of the BAM-positive region; arrowheads, BAM-positive cells. Scale bar, 10 µm; inset, 5 µm.