We aim to understand how cilia work and what their function is. Cilia are subcellular compartments that protrude from the surface of almost every mammalian cell. Cilia can be grouped into two major classes: a) primary cilia, which are immotile and b) motile cilia, which are also called flagella. A prominent example for the latter are sperm flagella. Ciliary dysfunction leads to severe diseases commonly referred to as ciliopathies. They comprise e.g. polycystic kidney disease, obesity, blindness, and infertility. However, the signaling pathways controlling ciliary function are ill-defined. To study ciliary signaling with high spatial and temporal precision, we combine optogenetics and genetically-encoded biosensors with high-resolution microscopy, mouse genetics, and biochemistry. This multidisciplinary approach allows not only to investigate ciliary signaling, but can be applied to any subcellular compartment to study its function with spatial and temporal resolution.
