Abstract

In my laboratory we use a multidisciplinary approach to study protein folding – how the linear sequence of amino acids in a polypeptide chain determines the structure to which it folds, the pathway by which it folds, and how it avoids misfolding. That is, how the primary sequence defines the entire energy landscape for folding.

It has recently become apparent that many proteins are not, in fact folded, but they play important roles in the cell. These intrinsically disordered protein challenge the structure : function paradigm, and they have attracted significant interest from investigators in the fields of structural biology, bioinformatics and theory, but, relatively little work has been done using standard biophysical kinetics techniques pioneered in studies of protein folding

Many key protein-protein interactions are driven by assembly of complexes where one or both partner proteins are intrinsically disordered before binding. In this case the free energy of binding has to compensate for the energetic cost of folding. We are comparing the folding of a number of different folding-upon binding systems to ask some fundamental questions about the mechanisms of folding upon binding: What is the importance of residual structure? What role does the ordered partner play? What is the mechanism of assembly? And, perhaps most fundamentally – what is the function of disorder? I will describe some of our recent findings.