Cross-Linking Mass Spectrometry for Investigating Protein Conformations and Protein-Protein Interactions-A Method for All Seasons

Mass spectrometry (MS) has become one of the key technologies of structural biology. In this review, the contributions of chemical cross-linking combined with mass spectrometry (XL-MS) for studying three-dimensional structures of proteins and for investigating protein-protein interactions are outlined. We summarize the most important cross-linking reagents, software tools, and XL-MS workflows and highlight prominent examples for characterizing proteins, their assemblies, and interaction networks in vitro and in vivo. Computational modeling plays a crucial role in deriving 3D-structural information from XL-MS data. Integrating XL-MS with other techniques of structural biology, such as cryo-electron microscopy, has been successful in addressing biological questions that to date could not be answered. XL-MS is therefore expected to play an increasingly important role in structural biology in the future.

Automated summary

Mass spectrometry (MS) is a key technology in structural biology, and chemical cross-linking combined with mass spectrometry (XL-MS) plays an important role in studying protein structures and protein-protein interactions. This review outlines the contributions of XL-MS, including cross-linking reagents, software tools, workflows, and significant examples, in characterizing proteins and their interactions in vitro and in vivo. Computational modeling and integration with other structural biology techniques have greatly enhanced the capabilities of XL-MS.