The Yeast Two-Hybrid System: A Tool for Mapping Protein–Protein Interactions

Virtually all processes in living cells are dependent on protein-protein interactions (PPIs). Understanding PPI networks is thus essential for molecular biology and disease research. One powerful genetic system for mapping PPIs both at a small scale and in a high-throughput manner is the yeast two-hybrid (Y2H) screen. In Y2H screening, PPIs are detected through the activation of reporter genes responding to a reconstituted transcription factor. In this introduction, we describe library- and array-based Y2H methods and explain their basic theory. We also include the rationale behind different Y2H approaches and strategies for optimizing results.