The Yeast Two-Hybrid Assay to Identify Interacting Proteins

The yeast two-hybrid assay invented by Stanley Fields and Stephen Elledge (1 –4 ) is a powerful tool to investigate protein-protein interactions, the essence of many biological processes. Owing to the adaptability of the assay procedure, the ease of manipulating and cultivating Saccharomyces cerevesiae , and the speed with which interacting proteins and their genes can be identified and characterized, this assay has been widely utilized and directly responsible for major discoveries in signal transduction and gene regulation (5 –7 ).