Research activities in the Mittag lab focus on intrinsically disordered proteins (IDPs) in signal transduction, in particular in the ubiquitination pathway. Proteins with long disordered regions are highly enriched in signal transduction and cancer associated pathways leading to the hypothesis that disorder is beneficial for mediating regulated protein-protein interactions. Such protein complexes can retain significant amounts of disorder instead of undergoing coupled binding and folding. The disorder in such dynamic protein complexes, in combination with post-translational modifications commonly used in signal transduction, may be utilized for the regulation of the affinity as a function of an input signal. IDPs therefore offer the opportunity to create sharp outputs, protein switches and exquisite control in signaling. We use NMR spectroscopy and other biophysical methods, combined with biochemical and computational approaches to biophysically characterize IDPs and correlate their properties with physiological function. Improving our understanding of IDP function may offer opportunities to target them pharmaceutically in the future.