Acts as component of the essential kinetochore-associated NDC80 complex, which is involved in chromosome segregation and spindle checkpoint activity. Component of the NDC80 complex, which consists of TID3/NDC80, NUF2, SPC24 and SPC25. The NDC80 complex is formed by two subcomplexes, TID3/NDC80-NUF2 and SPC24-SPC25, which are joined end-to-end through their coiled-coil domains. It has a rod-like structure with a length of 570 Angstroms and globular domains at either end. The TID3/NDC80-NUF2 globular domains are probably directed to microtubules, the SPC24-SPC25 globular domains to the centromere. Associated with kinetochores. Present with 1550 molecules/cell in log phase SD medium. Belongs to the NUF2 family.