An evolutionarily conserved neuroendocrine signalling pathway, the insulin/insulin-like growth factor signalling (IIS) pathway, controls ageing in a number of distantly related organisms. This control appears to result from a complex interaction of different tissues acting as signal emitters and receptors. Using systematic approaches, this project aims to identify the organs and tissues through which IIS affects ageing in Drosophila melanogaster.A combination of biochemical, histological and genetic techniques will be applied to whole adult flies in order to identify the organs/tissues capable of binding the relevant Drosophila Insulin-Like Peptides as well as those able to mount a transcriptional response to these peptides. Subsequently, the role of these signalling centres in ageing will be directly determined. In parallel a complex genetic screen is proposed to allow unbiased identification of the relevant organs and tissues based on a functional, phenotypic test. The study will yield a comprehensive understanding of the tissues involved in lifespan regulation by IIS and a solid framework for further investigation of the molecular basis of ageing.