Abstract: During the past years, numerous screens were carried out to gain insight into diverse signaling pathways. As screening project within the SFB1324, we will provide access to advanced screening resources and technologies to identify and characterize Wnt signaling pathway components. We will also provide guidance for genome engineering and high-throughput RNAi screening for our collaborators. Z3 will contribute various RNAi screening methodologies ranging from reporter gene assays to high-content automated microscopy. Furthermore, we will provide assistance for designing, conducting and analyzing RNAi screens as well as for CRISPR/Cas9-mediated genome engineering required for de novo screens and validation experiments. In addition, we will develop CRISPR/Cas9-mediated genome engineering approaches for the endogenous tagging of Wnt pathway components. The endogenously tagged Wnt ligands, receptors and cargo receptors can be used for single molecule and high-resolution microscopy essential for many projects within the SFB1324. We will use the CRISPR/Cas9-technology to endogenously label Wnt pathway components to study their secretion, trafficking and downstream signaling.