COMPETETIVE N-HYBRID SYSTEM

摘要

The invention relates to a method for identifying highly affinous ligands comprising the following steps: a) creating a bank for a mutagenized first hybrid protein comprising a plurality of mutants; b) expression of a first hybrid protein in a host with a second hybrid protein, one of the hybrid proteins comprising the DNA binding domain of a transcription factor and a bait protein and the other hybrid protein comprising the activation domain for a transcription factor and a prey protein; c) allowing the binding reaction between the first and second hybrid protein in order to form a complex with a functional transcription factor in the host cell under reaction conditions, which are such that the balance of the binding reaction is offset on the side of the hybrid proteins; d) detecting the binding reaction by detecting a reporter gene expressed via the functional transcription factor; e) optionally repeating a step or several steps from a) to d); f) selection of a mutant.