- Two-hybrid system
- The two-hybrid system is a method for identifying interacting proteins that uses transcriptional activity as a read-out. It relies on the modular nature of many site-specific transcriptional activators, which consist of a DNA-binding domain and a transcriptional activation domain. The DNA-binding domain targets the activator to the specific gene(s) that will be expressed, and the activation domain interacts with other proteins of the transcriptional machinery to enable transcription to occur. The 'bait' protein of interest is fused to the DNA binding molecule, the 'prey' to the transcriptional activator. The two-hybrid system is based on the observation that the two domains of the activator need to be non-covalently brought together by the interaction of the two proteins being studied.