Proteomics-Based Methods for Discovery, Quantification, and Validation of Protein–Protein Interactions

Abstract

Proteins play a fundamental role in establishing the diversity of cellular processes in health or disease systems. This diversity is accomplished by a vast array of protein functions. In fact, a protein rarely has a single function. The majority of proteins are involved in numerous cellular processes, and these multiple functions are made possible by interactions with other molecules. The complexity of interactions is substantially increased by the spatial and temporal diversity of proteins. For example, proteins can be part of distinct complexes within different subcellular compartments or at different stages of the cell cycle. Post-translational modifications can regulate and further expand the ability of proteins to establish localization- or temporal-dependent interactions. This complexity and functional divergence of interactions is further increased by the simultaneous presence of stable, transient, direct, and indirect protein interactions. Thus, an understanding of protein functions cannot be fully accomplished without knowledge of its interactions. Characterizing these interactions is therefore critical to understanding the biology of health and disease systems.