Fig. 4: In situ FA cross-linking of human PC9 cells in culture.

a Histogram of the distances spanned by in situ cross-links in cases that could be mapped onto solved atomic structures. The PDB IDs used for calculating these distances are listed in Supplementary Data 3 for each cross-link. b Docking model of the binding helix of βNAC (blue) on the outer surface of the S80 ribosome (PDBid 6EK0³⁹). The docking was constrained by two cross-links (red) to ribosomal protein L22 (green). Ribosomal protein L31 (magenta) was shown previously to interact with βNAC as well²⁹. c A view of the actin filament (PDBid 6D8C³¹), with one of its monomers marked in pink. Cross-links between actin and several of its regulators all map to the outer surface of the actin filament (red). d Docking model (green) of the CH3 domain of plastin-2 onto the actin filament. The docking was constrained by a single cross-link (red) between plastin-2 and actin. The model is similar (3.2 Å RMSD) to a recent cryo-EM structure (PDBid 6D8C³¹) of the homologous protein filamin A (yellow), which was assembled on the filament in vitro. Source data are provided as a Source Data file.