Figure 5
From: Intestinal FoxO signaling is required to survive oral infection in Drosophila
IMD triggers a regionalized AMP response in the adult midgut. Ectopic activation of the IMD pathway was achieved by overexpression of the soluble pattern recognition receptor (PRR) PGRP-LE in enterocytes (ECs) (NP1-Gal4 × UAS-FLAG-pgrp-le). Activation of the IMD pathway is shown by the occurrence of green fluorescent protein (GFP) under the control of a drosopmycin promotor. Drosomycin-promotor activity was observed in the proventriculus (a–c) in only a specific region. An overlay of 4,6-diamidino-2-phenylindole and green fluorescent protein (GFP) staining (a), GFP-staining only (b), and transmission light of the structure (c) are shown. Throughout, most regions of the midgut stem cells were labeled (d–j). Anti-GFP (e and h), anti-delta staining (f and i), or overlays of both signals (d, g and j) are shown. In the copper cell (CC) region, characteristic cells were labeled (k and m). Feeding 1-mM CuSO4-treated medium induced a fluorescent signal in the same cells (l). Confocal analysis revealed the cup-shaped structure of these cells, an opening with only a small pore toward the intestinal lumen (m). (n) Real-time PCR (RT-PCR) analysis performed with different regions of the larval anterior midgut, the proventiculus (PV), anterior midgut (AM), and the CC. Shown are the results of the RT-PCR experiments performed with oligonucleotides specific for the following gene products: LysA=lysozyme A, LysX=lysozyme X, attacin, defensin, drosomycin, cecropin, metallothionein A=(MtnA), soluble phospholipase A2 genes (sPLA2 and sPLA2GIII), as well as controls (rpL32) and the no template control (ntc).
