Role of the Drosophila Non-Visual ß-Arrestin Kurtz in Hedgehog Signalling

摘要: The non-visual s-arrestins are cytosolic proteins highly conserved across species that participate in a variety of signalling events, including plasma membrane receptor degradation, recycling, and signalling, can also act as scaffolding for kinases such MAPK Akt/PI3K. In Drosophila melanogaster, there is only single s-arrestin, encoded by kurtz, whose function essential neuronal activity. We have addressed the participation Kurtz during development imaginal discs, epithelial tissues requiring activity Hedgehog, Wingless, EGFR, Notch, Insulin, TGFβ pathways. Surprisingly, we found complete elimination kurtz genetic techniques has no major consequences cells. contrast, over-expression wing disc causes phenotype identical to loss Hedgehog prevents expression targets corresponding discs. mechanism which antagonises promote Smoothened internalization degradation clathrin- proteosomal-dependent manner. Intriguingly, effects on independent Gprk2 activation state receptor. Our results suggest fundamental differences molecular mechanisms regulating turnover vertebrates invertebrates, they could provide important insights into divergent evolution these organisms.