The Impact of Levels on Notch and Wg Signaling Pathways.

Awd, the homologue of metastasis suppressors, plays key roles in many signaling pathways. Mosaic analysis of the null allele showed that loss of gene function blocks Notch signaling and the expression of its target genes including the Wingless (Wg/Wnt1) morphogen. We also showed that RNA interference (RNAi)-mediated silencing () in larval wing disc leads to chromosomal instability (CIN) and to Jun amino-terminal kinases (JNK)-mediated cell death. Here we show that this cell death is independent of p53 activity. Based on our previous finding showing that forced survival of -CIN cells leads to aneuploidy without the hyperproliferative effect, we investigated the Wg expression in wing disc cells. Interestingly, the Wg protein is expressed in its correct dorso-ventral domain but shows an altered cellular distribution which impairs its signaling. Further, we show that RNAi-mediated knock down of in wing discs does not affect Notch signaling. Thus, our analysis of the hypomorphic phenotype arising from downregulation uncovers a dose-dependent effect of Awd in Notch and Wg signaling.