A role of JNK signaling in intra-organ growth.

(A-C) Wing imaginal discs from individuals expressing GFP, RA^CS or dmyc^RNAi and stained to visualize GFP (A-C), puckered-lacZ (A) and Mmp1 (B-C). (D-I) Wing discs labeled to visualize Mmp1 protein expression from individuals expressing dmyc^RNAi alone or in combination with Dmp53^RNAi (E), Bsk^DN (F), hep^r75/+ (G), egr^RNAi (H) and grnd^RNAi (I). (J) qRT-PCR showing mmp1 mRNA levels in wing discs expressing the indicated transgenes under the control of the en-Gal4 driver. (K) Histogram plotting PH3 positive cells in the anterior (A) compartment of wing imaginal discs from individuals expressing the indicated transgenes under the control of en-Gal4. (L) Representative adult wings from individuals expressing the indicated transgenes in posterior compartment (blue) under the control of en-Gal4. The expected size of the neighboring domain to give rise to a well-proportioned adult wing is depicted. (M) Histogram plotting normalized area of the posterior (P; blue bars) and anterior (A; grey bars) compartments of adult wings from individuals expressing RA^CS along with the indicated transgenes with en-Gal4. Blocking JNK pathway by co-expression of Tak^DN, Bsk^DN or Fos^DN totally reverted the non-autonomous reduction in tissue size caused by RA expression. ** p<0.01. (N-O) Wing imaginal discs from individuals expressing RA^CS along with the indicated transgenes under the control of en-Gal4 and stained to visualize TUNEL (N) and BrdU incorporation (O).