In this project, we will use a technology – developed jointly by the participating groups at ETH – that provides unique insight into the molecular organization of protein-RNA complexes. The method is based on cross-linking with ultraviolet light to stabilize interactions between protein and RNA. We will then use a technique called mass spectrometry to identify interacting regions. The approach, termed CLIR-MS, has already provided valuable insights for other protein-RNA complexes. In this Technology Translation project, we will extend the application of the method to samples of clinical relevance (cell lines, brain and muscle tissue), to derive a new kind of interaction marker that takes the structural and functional context into account.