Efficient yeast one-/two-hybrid screening using a library composed only of transcription factors in Arabidopsis thaliana.

Yeast one-hybrid screening is widely used for the identification of transcription factors (TFs) that interact with specific DNA sequences. However, screening a whole cDNA library is not efficient for the identification of TFs because TF genes represent only a small percentage of clones in a cDNA library. Here, we present the development of an efficient yeast one-hybrid screening system using a prey library composed only of approximately 1,500 TF cDNAs of Arabidopsis thaliana. This library enabled us to isolate a TF that binds to a specific promoter sequence with high efficiency, even when the promoter region of the gene of interest was directly employed as bait. Furthermore, this library was also successfully applied as a yeast two-hybrid library to find TFs that interact with specific proteins. This efficient system will contribute to the elucidation of gene regulatory networks in plants.