This gene encodes a component of the kinetochore-associated NDC80 protein complex, which is required for the mitotic spindle checkpoint and for microtubule-kinetochore attachment. During meiosis in mouse, the protein localizes to the germinal vesicle and then is associated with the chromosomes following germinal vesicle breakdown. Knockdown of this gene in oocytes results in precocious polar body extrusion, chromosome misalignment and aberrant spindle formation. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Apr 2015]