Global Identification of Caspase Substrates Using PROTOMAP (Protein Topography and Migration Analysis Platform)

Abstract

Delineation of the natural substrate scope of proteases is important for understanding the functions of proteolytic pathways in physiology and disease. Herein we describe the protocol for PROTOMAP, a technique that combines SDS-PAGE with tandem mass spectrometry to globally identify shifts in protein migration indicative of proteolytic processing. When applied to cells undergoing apoptosis, this unbiased global method provides a snapshot of the topography and magnitude of proteolytic events associated with programmed cell death.