Acts as a component of the essential kinetochore-associated NDC80 complex, which is required for chromosome segregation and spindle checkpoint activity to ensure proper cell division. Required for the maintenance of plant architecture. Component of the NDC80 complex, which consists of NDC80, NUF2, SPC24 and SPC25. Colocalizes with CENH3 at the centromere. Highly expressed in actively dividing tissues, such as shoot apical meristem (SAM), root apical meristem (RAM), vasculature, newly emerging leaves and inflorescence shoots. Embryonic lethality due to division arrest before the globular stage. Belongs to the SPC24 family.