Understanding how organs grow to a defined size and are correctly patterned is a problem of fundamental importance. Many of the essential processes that regulate organ growth become deregulated in diseases such as cancer; therefore it is imperative that we develop a thorough understanding of the genes involved. This will enable the identification of potential therapeutic targets. The eye of Drosophila melanogaster has been studied extensively in the context of organ growth and tissue development, and due to high genetic and functional conservation, has provided many key insights into mammalian development and disease. However, there remain many gaps in our understanding, both in terms of the genes that are involved and the mechanisms by which they act to ensure a correctly developed adult organ.
In order to identify novel regulators of growth in the Drosophila eye, we carried out a genetic screen. Mutations were induced randomly with ethyl methanesulfonate, and clones of mutant tissue were allowed to grow in a wild type background. The effect of these mutations on development of the eye was then assessed by comparison to surrounding wild type tissue. By this method, we isolated an allele termed d2D.2, which gives rise to an overgrown, rough eye. This mutation was characterised by deficiency complementation and sequencing, and the phenotype was characterised by clonal analysis. The mutation was found to disrupt growth and patterning of the developing Drosophila eye and affect the transcriptional output of a number of key developmental regulators, including Notch and Hippo signalling. These results further our understanding of the mechanisms governing organ development in Drosophila and highlight potential avenues of further research in mammalian systems.