Figure 1. BMP signaling inhibits Dl-independent N pathway activity to promote ISC self-renewal.
(A) A scheme for the ISC lineage in Drosophila midgut. (B-E’’) Representative images of Control guts (B-B’’), midguts expressing UAS-Put-RNAi (C-C’’), UAS-Dl-RNAi (D-D’’), or UAS-Put-RNAi + UAS-Dl-RNAi (E-E’’) with esg-Gal4ts, UAS-GFP at 29°C for 10 days and immunostained for Su(H)-lacZ (grey or red) and GFP (green). Su(H)-lacZ is used as a marker for EB. DAPI (blue) staining indicates nuclei. Compared with control guts (B-B’’), Put knockdown (C-C’’) in precursor cells (green) caused an increase of EB pairs. Dl knockdown induced stem cell-like tumor. Put and Dl double knockdown induced a dramatic increase of EBs. Scale bar (20 μm) is shown in B.