Driving Integrative Structural Modeling with Serial Capture Affinity Purification
Liu X, Zhang Y, Wen Z, Hao Y, Banks CAS, Lange JJ, Slaughter BD, Unruh JR, Florens L, Abmayr SM, Workman JL, Washburn MP(2020) Proc Natl Acad Sci U S A 
- PubMed: 33257578 
- DOI: https://doi.org/10.1073/pnas.2007931117
- Primary Citation of Related Structures:  
9A0P - PubMed Abstract: 
Streamlined characterization of protein complexes remains a challenge for the study of protein interaction networks. Here we describe serial capture affinity purification (SCAP), in which two separate proteins are tagged with either the HaloTag or the SNAP-tag, permitting a multistep affinity enrichment of specific protein complexes. The multifunctional capabilities of this protein-tagging system also permit in vivo validation of interactions using acceptor photobleaching Förster resonance energy transfer and fluorescence cross-correlation spectroscopy quantitative imaging. By coupling SCAP to cross-linking mass spectrometry, an integrative structural model of the complex of interest can be generated. We demonstrate this approach using the Spindlin1 and SPINDOC protein complex, culminating in a structural model with two SPINDOC molecules docked on one SPIN1 molecule. In this model, SPINDOC interacts with the SPIN1 interface previously shown to bind a lysine and arginine methylated sequence of histone H3. Our approach combines serial affinity purification, live cell imaging, and cross-linking mass spectrometry to build integrative structural models of protein complexes.
- Stowers Institute for Medical Research, Kansas City, MO 64110.
Organizational Affiliation: