Coupled binding and folding of intrinsically disordered proteins: what can we learn from kinetics?

Protein or protein regions that are not forming well-defined structures in their free states under native-like conditions are called intrinsically disordered proteins. Such proteins are very common in protein–protein interactions, where their disorder apparently gives several advantages including optimal binding properties. To fully appreciate why protein disorder is advantageous for protein–protein interactions we need to understand the mechanism(s) of interaction. However, elucidating mechanisms in protein–protein interactions is usually very challenging. Here we discuss how kinetics in combination with protein engineering and structural information can be used to depict details of protein–protein interactions involving intrinsically disordered proteins.