Chemical cross-linking of the Spindly-RZZ complex followed by mass spectrometry

Kinetochores are macromolecular assemblies that connect chromosomes to spindle microtubules during mitosis. The metazoan-specific ≈800 kilodalton ROD-Zwilch-ZW10 (RZZ) complex builds a fibrous corona that assembles on mitotic kinetochores prior to microtubule attachment to promote chromosome alignment and robust spindle assembly checkpoint signaling. Here, we combine biochemical reconstitutions, single particle electron cryo microscopy, cross-linking mass spectrometry, and structural modeling to build a complete model of human RZZ