Small Molecule-Protein Interaction three-hybrid assay

The yeast three-hybrid (Y3H) system is a cellular assay system designed for the identification and characterization of small molecule-protein interactions in intact cells [25]. It uses yeast Saccharomyces cerevisiae as a host system and combines aspects of the yeast two-hybrid (Y2H) system [26] with recent developments in chemical dimerizer technology [27, 28],... 

Just as a dimeric RNA molecule can be introduced to mediate the interaction between the DNA-binding and ADs, so can a dimeric small molecule [17]. In fact, well before their use in a small molecule three-hybrid assay, dimeric small molecules were used as chemical inducers of dimerization (CIDs) to artificially oligomerize fusion proteins in vivo [18]. In the yeast three-hybrid system, the union of two protein fusions and a CID reconstitute the transcription of a reporter gene (Fig. 4.1-3(d)). In 1996, Licitra and Liu built what they called a yeast three-hybrid assay [19]. This assay consists of two fusion proteins and a heterodimeric small molecule CID that brings these fusion proteins together to activate the transcription of a reporter gene (Fig. 4.1-3 d)). 

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