Plant Transcription Factors

Volume 754 of the series Methods in Molecular Biology pp 145-165


Yeast Protein–Protein Interaction Assays and Screens

  • Stefan de FolterAffiliated withLaboratorio Nacional de Genómica para la Biodiversidad (LANGEBIO), Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV-IPN) Email author 
  • , Richard G.H. ImminkAffiliated withPlant Research International, Centre for BioSystems Genomics (CBSG)

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Most transcription factors fulfill their role in protein complexes. As a consequence, information about their interaction capacity sheds light on a protein’s function and the molecular mechanism underlying this activity. The yeast two-hybrid GAL4 (Y2H) assay is a powerful method to unravel and identify the composition of protein complexes. This in vivo based system makes use of two functional protein domains of the GAL4 transcription factor, each fused to a protein of interest. Upon interaction between the two proteins under study, a transcriptional activator gets reconstituted and reporter genes get activated, allowing the yeast to grow on selective medium. In this chapter protocols are given for Y2H library screening, directed Y2H screening, Y2H matrix screening, and YnH screening involving more than two proteins.

Key words

Protein–protein interactions yeast two-hybrid Y2H YnH GAL4 system complexes transcription factors