Animal growth is a complex process that is intimately linked to the developmental program in order to form fit adults with proper size and proportions. Genetics is an important determinant of growth, exemplified by the role of local diffusible molecules in setting organ proportions for a given species. In addition to this genetic control, organisms use adaptation mechanisms allowing modulating the size of individuals according to environmental cues, among which nutrition. Therefore, sophisticated cross-talks between local and global cues are at play for the determination of the final size of an individual. The major objective of this project is to tackle the mechanisms involved in coupling growth control with environmental cues, as well as the mechanisms participating in growth arrest and the determination of final size.Our project proposes a blend of physiological and genetic approaches on the Drosophila model, with the use of tissue-targeted loss-of-function to unravel some of the important cross-talks existing between organs for the control of growth at the global level. We will develop these approaches to (i) unravel the molecular nature of tissue cross-talks involved in nutrient sensing and the control of insulin/IGF secretion; (ii) tackle the feed-back mechanisms linking the developmental clock to the growing state of tissues and organs.These projects should bring new contributions in two separate fields related to growth control, Developmental Biology and Physiology, in an attempt to merge these complementary approaches into a broader vision of this fascinating biological question.