Protein zwilch homolog (ZWILCH)

Essential component of the mitotic checkpoint, which prevents cells from prematurely exiting mitosis. Required for the assembly of the dynein-dynactin and MAD1-MAD2 complexes on kinetochores.

Its function related to the spindle assembly machines is proposed to rely on its association from the mitotic RZZ complicated (PubMed:15824131). .