We want to identify novel target genes of the canonical Wnt pathway, which is often aberrantly activated in human cancer. These genes will be identified in different organs of transgenic tadpoles (Xenopus) in which the Wnt pathway is genetically manipulated. To functionally characterize these genes we will perform overexpression and knock-down experimemnts in tadpoles expressing different fluorescent reporter genes. For this we will use a fluorescent steromicroscope with a time lapse module.