IDPs that Fold Upon Binding: What is the Role of the Partner Protein?

Many intrinsically disordered proteins perform their functions within the cell by binding to a partner protein, often forming a defined structure (such as a helix or an extended strand) when they bind. To date most studies of coupled folding and binding have centred on the disordered protein or peptide, giving little consideration to the folded partner protein. Our recent work with ‘model’ IDP systems reveals that the folded partner protein can play an unexpectedly important role in the binding process.