Mammalian protein interaction cloning system

摘要

The present invention is directed to compositions and methods for a genetic system of detecting protein-protein interactions in a mammalian host cell. Two fusion proteins are made in the host cell. The first fusion protein contains a DNA binding domain which is fused to a so-called bait protein. The second fusion protein consists of a transcriptional activation domain fused to a so-called test protein. The DNA binding domain binds to an operator sequence which controls expression of one or more reporter genes. The transcriptional activation domain is recruited to the promoter through the functional interaction between the bait protein and the test protein. Subsequently the transcriptional activation domain interacts with the basal transcription machinery to activate expression of one or more reporter genes which can be identified and characterized. The individual compositions are useful for analyzing protein-protein interactions between known proteins and to isolate, clone and characterize unknown proteins. The individual compositions can be used to express the fusion proteins either transiently or stably. In addition, the present invention is directed to methods for screening for candidate bioactive agents that modulate the protein-protein interaction between a bait protein and a test protein and thus are useful for the identification of novel therapeutic drugs and the like.