Using immunoprecipitation to study protein-protein interactions in the Hedgehog-signaling pathway.

The Hedgehog (Hh)-signaling pathway has been intensively studied in the past decade. Increasing evidence suggests that dynamic formation of protein complexes plays a critical role in the organization and regulation of Hh signaling. Immunoprecipitation (IP) is a powerful tool to study protein-protein interactions and has provided important insights into the regulation of Hh signal transduction. Here, we show how to use IP to study protein-protein interactions in the Drosophila Hh-signaling pathway.