The Grow'n'Glow GFP Yeast Two-Hybrid System is a two-hybrid assay used to investigate protein interactions. This assay can characterize the domains, amino acid residues, and conditions necessary for known protein interactions and identify new interacting proteins. The screening ability of the two-hybrid approach makes it a powerful tool for gene discovery and functional analysis.
The Grow'n'Glow GFP system simplifies and accelerates the screening process of two-hybrid systems tremendously. It combines the advantages of the well-known gene expression reporter protein GFP (green fluorescent protein) with the LexA based yeast two-hybrid technology. The GFP reporter causes yeast colonies with interacting proteins to glow bright green. As a result, protein-protein interactions can be detected in vivo in a one-step selection under UV light. Time-consuming beta-galactosidase lift assays are not involved, unlike conventional two-hybrid assays. Fewer false positives are present due to the use of prokaryotic (LexA and B42) rather than eukaryotic (GAL4) proteins.
Interacting proteins result in expression of two reporter genes - the LEU2 nutritional selection gene and the GFP gene from Aequorea victoriae. Expression of LEU2 allows yeast with interacting proteins to grow on medium lacking leucine, and expression of the GFP gene is readily detected by visualizing colonies under UV light. Use of the tightly controlled LEU2 and the easily detectable GFP reporters reduces background and offers more clear-cut results, expediting the entire screening process.