Hedgehog (Hh) pathway is widely involved in cell growth and differentiation during both vertebrate and invertebrate development. Malfunction of Hh pathway could cause various human diseases, including birth defects and cancers. In Drosophila, Cubitus interruptus (Ci), the homologue of mammal Glioblastomas (Gli), is a key transcription factor of Hh pathway. The activity and stability of Ci/Gli are regulated by Hh concentration, and further precisely induce downstream gene expressions.
