Structure and Plasticity of Protein-protein Interfaces in Factor Xa and the Androgen Receptor

Like the cells they operate, proteins are dynamic, plastic entities. Nowhere in proteins is this more evident than in protein-protein interfaces. In many cases, proteins must be able to recognize not just one partner, but many. The ability to be flexible and accommodating, yet at the same time discriminate against the multitude of unwanted partners in the cell is what allows proteins to make life possible. However, this presents a paradox: how can protein recognition be both specific and promiscuous? In particular, what are the mechanisms that allow broad-specificity in a protein-protein interface, and perhaps more importantly, what insights can this give us toward understanding a protein's biological role in the cell? Answering these questions can potentially lead to new compounds that antagonize protein-protein interfaces and cure disease.