ISCs are stained with Dl (magenta) and EEs with Prospero (magenta). C to B). This defect is usually suppressed in double mutants (D). (E) In contrast to the control guts, which exhibit a monolayer intestinal architecture, the mutant guts are multi-layered. This defect is usually rescued in or double mutants. **** P<0.0001 (t-test). (F) Compared to controls, the maximum epithelial Procyanidin B1 height is usually greatly increased in mutants. The height is usually reverts to a normal level upon concomitant loss of or mutants at eclosion. Excess numbers of progenitor cells, marked by (green), are readily detected in newly eclosed mutant guts (compare C-C to A-A; high magnification view: compare D-D to B-B). The cell-cell junctions, which are marked by Arm (magenta), remained largely intact at this stage (compare C to A; high magnification view: compare D to B).Scale bars: (A-A and C-C) 50 m, (B-B and D-D) 10 m. Genotypes: control: mutant ISC defects are not present before pupation. (A-B) Numbers of AMPs (adult midgut progenitors), marked by (green), are comparable between control and mutant guts.(C-D) The cell-cell junctions, marked by membrane-associated Discs large 1 (Dlg1, magenta), remain intact at this stage. Scale bars: (A-B) 10 m, (C-D) 50 m. Genotypes: control: activity either during development of the adult gut or during adulthood results in excess progenitor cells. (A-D) expression, knocked down using the driver during formation of the adult gut (crosses were shifted from 18C to 29C during second instar larval stage and the progeny of desired genotype were examined 2C3 days post-eclosion), results in excess progenitor cells. Progenitor cells are identified as small cells with strong Arm staining and lack of Prospero staining (magenta) or by (green). Nuclei are Procyanidin B1 labeled with DAPI (blue). Low magnification view: A-A (control) and C-C (RNAi); high magnification view: B-B (control) and D-D (RNAi).(E-F) expression, knocked down using the driver during adulthood (progeny of desired genotype were shifted from 18C to 29C after eclosion and analyzed 14 days later), also results in excess progenitor cells (marked by RNAi); high magnification view: F-F (control) and H-H (RNAi). (I) Quantification of progenitor cell numbers when expression is usually knocked down during formation of the adult gut or during adulthood reveals dramatic increases in both contexts. **** P<0.0001 (t-test). Scale bars: (A-A, C-C, E-E and G-G) 50 m, (B-B, D-D, F-F and H-H) 10 m. Genotypes: knockdown induces ISC proliferation/self-renewal in the midgut during adulthood. (A-B) Knockdown of expression during adulthood (2C3 Procyanidin B1 day aged adults of the desired genotypes were shifted from 18C to 29C for 14 days before analysis) results in increased stem/progenitor cell self-renewal (marked by GFP, green) using the stem/progenitor and lineage tracing flip out system. Nuclei are labeled with DAPI (blue). PM: posterior midgut; AM: anterior midgut; CCR: copper cell region.(C) Quantification of ISC proliferation by pH3 scoring upon knockdown during adulthood. PMG: posterior midgut. **** P<0.001 (t-test). Number of guts (n): control guts: n = 14 and guts: n = 7. (D) Measurement COPB2 of total GFP area in posterior midguts (PM) of control and adult-specific RNAi driven by the flip outsystem. *** P<0.001 (t-test). For both conditions, 2 pictures in different regions of the posterior midgut were taken for each midgut, n = 5. Scale bars: (A and B) 100 m, (A-A) and (B-B) 50 m. Genotypes: and resulting from loss requires Ebd and Ewg. Growth of (magenta; A and B) and (magenta; E and F) expression upon loss of is usually suppressed by inactivation of (C and G) or (D and H). Anterior to the left. Scale bars: 100 m.Genotypes: Procyanidin B1 (A-D) control: (same gut.