Small kinetochore-associated protein (Knstrn)

Essential component of the mitotic spindle required for faithful chromosome segregation and progression into anaphase. Promotes the metaphase-to-anaphase transition and is required for chromosome alignment, normal timing of sister chromatid segregation, and maintenance of spindle pole structure.

The astrin (SPAG5)-kinastrin (SKAP) complex promotes steady microtubule-kinetochore attachments. Required for kinetochore oscillations and dynamics of microtubule plus-ends during live cell mitosis, possibly by forming a link between spindle microtubule plus-ends and mitotic chromosomes to attain faithful cell division.