Kinetochore Created 2026-10-14 Updated 2026-10-20
A kinetochore is a protein assembly at a centromere that attaches a chromosome to microtubules of the spindle apparatus. Each replicated chromosome has sister kinetochores; their attachment and subsequent separation help distribute the copied material. A kinetochore is therefore the attachment machinery, while the centromere is its chromosome site.[ref]
The kinetochore ablation experiment tests this mechanical role directly. Counting kinetochores as independent chromosomes before sister separation would confuse duplicated attachment machinery with ploidy.