Teeth form as appendages of embryonic ectoderm and their development is regulated by similar mechanisms to other ectodermal organs like hairs and glands. More than 300 genes are currently known to be involved in tooth development. However, the mechanisms that regulate gene expression at specific times and locations are only partially understood. The most interesting open questions concern the mechanisms of the initial acquisition of organ specificity and the regulation of stem cells. microRNAs (miRNAs) constitute a class of short regulatory RNAs that control gene expression post-transcriptionally. Their involvement in the genetic network regulating tooth development and dental stem cells has not been explored yet. This project aims to identify the miRNAs involved in the development of teeth as well as some other ectodermal organs and dental stem cells. The identification and analysis of the roles of miRNAs and their mRNA targets will be performed using bioinformatics linked to classical developmental/molecular/cell biology methods as well as novel sophisticated technologies such as miRNA microarray analysis and inhibition studies with tissue electroporation and LNAs. The results are expected to contribute to the development of novel clinical applications in the field of tissue regeneration and stem cells. The project will join an experienced researcher from ectodermal organ formation field and an internationally well-known group in tooth development to enhance European competitiveness and excellence in developmental and regenerative biology. This project gives the opportunity to increase the researcher's independency and to work in a very timely area. He will learn new skills, such as microarrays and miRNA technologies and acquire training in important bioinformatic tools, all important for the future career. In addition, this project will help him to develop an international scientific network.