Figure 1

Dietary regulation of GSC niche size. (A) Diagram of anterior germarium. (B) Cap cell niche (arrow) marked with anti-Coracle (purple) and anti-laminC (green). GSCs (arrow heads) marked by spherical spectrosomes (anti-spectrin, also, green). (C) Cap cell number is maintained on standard medium or when additionally supplemented with yeast paste (St + Yeast). (D) Decline of GSCs with age shows no significant difference on standard food with or without yeast paste. (E) Cap cells decline when adults are maintained on Protein/Glucose (P/G)-depleted medium or agar only (P < 0.05, t-test of slope coefficients of P/G depleted or agar only compared with Standard or St + Yeast media depicted in (A). Cap cells recover after shifting flies to St + Yeast, when comparing recovered time point with time of shifting to rich food. (F) GSCs decline similarly with age on P/G-depleted, Standard and St + Glucose, showing no significant differences. Flies kept on agar lose GSCs after 6 days compared to flies on P/G-depleted food. However GSC decline is delayed when flies initially kept on P/G-restricted food are shifted to St + Yeast, compared to either unshifted flies or to flies kept constantly on St + Yeast depicted in panel D (p < 0.05, comparing day 33 time points). Data shown in C, D and E, F as mean ± SEM and were obtained concurrently. For C, D n = 36 to 60 (except St + Yeast, day 33, n = 15); for E, F n = 32 to 60. * indicates P < 0.05, ** P < 0.01, *** P < 0.001, Mann Whitney U-test. (G) Example of reduced size niche (arrow), from fly kept 6 days on agar. (H) Example of recovered niche after transferring back to St + Yeast for further 9 days. GSCs marked by arrowheads. Staining as in B.