Principle

Yeast one hybrid is a technology developed on the basis of yeast two-hybrid. It is mainly used to study the interaction between proteins and DNA elements.

The transcription initiation of eukaryotic genes requires the participation of transcription factors. Transcription factors usually consist of a DNA-specific binding domain and one or more activation domains that interact with other regulatory proteins, namely DNA binding. Domain (DNA-bindingdomain BD) and transcription activation domain (activationdomain, AD). The yeast GAL4 protein used in the yeast one-hybrid system is a typical transcription factor. The DNA-binding domain of GAL4 is close to the hydroxyl end and contains several zinc finger structures that can activate the upstream activation site (UGS) of yeast galactosidase. , and the transcription activation domain can interact with RNA polymerase or the transcription factor TFIID to increase the activity of RNA polymerase. In this process, the DNA-binding domain and the transcriptional activation domain can function completely independently. Based on this, we can replace the DNA-binding domain of GAL4 with a transcription factor-encoding gene, and connect the cis-acting element to the minimal promoter (minimal promoter, Pmin) and reporter gene. As long as the transcription factor can interact with the target DNA element, the RNA polymerase can be activated through the transcription activation domain, and the transcription of the reporter gene downstream of the promoter can be activated.