ELYS binds to MAD1L1 and MAD2L1 in mitotic cell lysates and to MAD1L1 in
vitro. (A) BioID2-Myc (empty vector, EV), BioID2-Myc-MAD1L1, or
BioID2-Myc-MAD2L1-inducible HeLa stable cell lines were induced with Dox and treated
with 100 nM Taxol to arrest cells in mitosis. Mitotic cell lysates were then used for
Myc immunoprecipitations and subjected to immunoblot analysis with the indicated
antibodies. Note that endogenous ELYS immunoprecipitates with BioID2-Myc-tagged MAD1L1
and MAD2L1. Asterisks indicate BioID2-Myc-MAD1L1 or BioID2-Myc-MAD2L1 in the inputs or
eluates. The arrowhead indicates a nonspecific background band recognized by the
anti-BioID2 antibody. (B)35S-radiolabeled Myc-ELYS N-terminal
fragment (ELYS1-46, first 46 amino acids); FLAG-MAD1L1, FLAG-MAD2L1, and FLAG-GFP
(control) were used in in vitro binding assays. Myc
immunoprecipitations were resolved by western blotting and the blots were analyzed by
autoradiography. Note that the ELYS N-terminal fragment binds to MAD1L1 (indicated by
the asterisk in the eluate) and not MAD2L1.