Isotope-Coded and Affinity-Tagged Cross-Linking (ICATXL):An Efficient Strategy to Probe Protein Interaction Surfaces

摘要

Protein bait affinity studies on the yeast proteome have begun to reveal the nature and complexity of cellular protein-protein interactions.However,our knowledge of the actual recognition interfaces among these macromolecules is sparse.To gain mechanistic insights into various cellular processes,it is important to devise strategies that enable the mapping of protein-protein interaction surfaces even at low resolution.We and others have recently shown that valuable spatial restraints can be obtained from chemical cross-linking of protein assemblies through use of tandem mass spectrometry to identify the specific cross-linked amino acid participants.Such investigations provide information on protein folding,connectivity of secondary structures,as well as interaction surfaces.