Kinetochore proteins beyond chromosomes – emerging links to vesicles and microtubules

Kinetochores are molecular architects of accurate eukaryotic cell division, functioning to link chromosomes to microtubules. However, kinetochore protein function might have non-chromosomal origins. Study of ancestral division machinery argues for a close association of ancient kinetochore proteins in vesicle trafficking-based processes. Moreover, increasing evidence supports the idea that kinetochore proteins function away from chromosomes in processes involving vesicles and associated microtubules. In turn, vesicle proteins also regulate chromosomal kinetochore function. This Opinion article summarizes evidence that kinetochore proteins have prominent localization to and function in non-chromosome-based processes that often involve vesicles. We argue that these non-chromosomal roles for kinetochore proteins provide insight into under-appreciated functions for these well-studied proteins and shed light on the origin of, and coordination between, crucial cellular machinery.