Protein recruitment systems for the analysis of protein-protein interactions

Following the completion of genome projects in a number of organisms, it is becoming evident that a relatively large proportion of the genes identified encode for proteins that have no sequence homology with known proteins. One possible approach towards understanding protein function is to identify the proteins with which a particular protein associates. Although very powerful, the most commonly used genetic method, the two-hybrid system, is limited in its ability to detect all possible protein-protein interactions. The development of novel approaches, such as the protein recruitment systems, provides attractive alternatives towards identification of protein-protein interactions where other methods have failed to function.