Research Paper Volume 1, Issue 7 pp 637—651

Figure 5. D-p38b MAPK plays a role in oxidative stress-induced aberrant Delta/ Notch signaling within the adult midgut. (A) Effect of D-p38b knockdown in ISCs and EBs on oxidative stress-induced accumulation of abnormal large esg- and Su(H)GBE-positive cells within the adult midgut. The midguts of 5-day-old esg>+;Su(H)GBE-lacZ (a-f) or esg>UAS-D-p38bas;Su(H)-GEB-lacZ (g-l) flies exposed to 10 mM PQ in 1% sucrose (d-f and j-l) or 1% sucrose media control (a-c and g-i) were labeled for 16 h with anti-GFP (a, d, g, and j) and anti-?-gal (b, e, h, and k - red). (c, f, i, and l) merged image. (DAPI, blue) Arrow indicates EC-like large esg-GAL4. Asterisk indicates large Su(H)GBE-positive cell. Scale bar, 5 µM. (B) Effect of D-p38b knockdown on oxidative stress-induced increase of Delta expression. The level of Delta mRNA was measured by quantitative RT-PCR of dissected guts from 5-day-old esg>+, esg>UAS-D-p38bas flies exposed to 10 mM PQ in 1% sucrose or 1% sucrose media control for 16 h. Expression was normalized to the expression of rp49. The level of Delta mRNA in midgut of 5-day-old flies was set as 1. White bar, 1% sucrose media; black bar, 10 mM PQ in 1% sucrose media. P-values were determined using Student′s t-test.