Probable component of a centromeric complex involved in assembly of kinetochore proteins, mitotic progression and chromosome segregation. May play an important role in chromosome congression and in the recruitment of CENP-O complex (which comprises CENPO, CENPP, CENPQ and CENPU), CENPE and PLK1 to the kinetochores. Localizes exclusively in the centromeres. Belongs to the CENP-Q/OKP1 family.