Isothermal Titration Calorimetry Assays to Measure Binding Affinities In Vitro

Abstract

In the study of the Hippo signal transduction pathway, protein-protein interactions are often explored, because various proteins such as MOB1, NDR1/NDR2, and LATS1/LATS2 are very important members in this complicated signaling pathway. The transduction of signals from upstream to downstream is largely dependent on the mutual recognition of proteins and the formation of specific non-covalent complexes between them. In general, protein-protein associations, protein–DNA associations, or protein-small molecule associations cause the release or absorption of heat during the association reaction. The isothermal titration calorimetry (ITC) assay is a convenient and widely used approach to directly measure the amount of heat released or absorbed during association processes of biomolecules (such as protein-protein, protein-DNA, or protein-small molecules) in solution and to quantitatively estimate the interaction affinity.