We plan to study the mechanism that controls the growth of animal tissues. We will focus on two types of mitotic modes: asymmetric cell divisions and the morphogen-dependent proliferation of developing cells. Our recent work has shown that endosomal trafficking plays key roles during asymmetric division and during the formation of morphogen gradients. We therefore plan to unravel the biochemical and cell biological mechanisms underlying the key role of endosomes during growth control using Drosophila as a model system and validating it in the Zebrafish, where we will also discover the new endosomal properties that emerged in vertebrates. Our project will pursue two aims: 1. to discover the key lipids and proteins involved in the endosome-mediated control of growth; 2. to study at the biophysical level the signaling and membrane trafficking events that, emanating from the endosomes, mediate the control of growth. We have already shown that endosomal trafficking is essential during the formation of morphogen gradients and asymmetric cell division. This proposal ultimately aims at the physical, molecular and cellular mechanisms behind.