Dynein intermediate chain 2c (DNCI2c) complex is essential for exiting Mad2-dependent spindle assembly checkpoint

The Mad2 protein plays a key role in the spindle assembly checkpoint (SAC) function. The SAC pathway delays mitotic progression into anaphase until all kinetochores attach to the spindle during mitosis. The formation of the Mad2–p31^comet complex correlates with the completion of spindle attachment and the entry into anaphase during mitosis.Herein, we showed that dynein intermediate chain 2c (DNCI2c)—a subunit of dynein motor protein—forms an immunocomplex with p31^comet during mitosis. DNCI2c-knockdown resulted in prolonged mitotic arrest in a Mad2-dependent manner. Furthermore, DNCI2c-knockdown-induced mitotic arrest was not rescued by p31^comet overexpression. However, the combination of p31^comet overexpression with the mitotic drug treatment reversed the mitotic arrest in DNCI2c-knockdown. Together, these results indicate that the DNCI2c–p31^comet complex plays an important role in exiting Mad2-dependent SAC.