Progress and potential of Drosophila protein interaction maps

Protein-protein interactions mediate many important cellular processes and are central to the mechanisms by which most proteins function. Charting the interactions among the proteins involved in a process has been an essential step in characterising the function of proteins and pathways. The yeast two-hybrid system is one approach to detecting protein interactions that can now be scaled-up to assay large sets of proteins systematically, such as those being identified from genome sequencing efforts. The system has already been extensively used to acquire data that have enabled construction of large protein interaction maps (PIMs). When combined with other data, including data being generated by other functional genomics approaches, PIMs help assign function to new proteins and delineate functional networks. Hypotheses generated in such a manner often must be tested by additional experimentation, preferably in vivo. The model organism Drosophila melanogaster has a wealth of genetic and bioinformatic tools available for such analyses. The proteome predicted from the recently sequenced Drosophila genome indicates that humans have more genes in common with Drosophila than with any other invertebrate model organism characterised to date. Thus, the construction and characterisation of Drosophila PIMs will help define the functions of many conserved genes and pathways, and will provide the pharmaceutical research industry with invaluable data to assist with drug target identification and validation.