<P> Kinetochore: protein structure found at the centromere of a chromatid to which microtubules attach to during cell division . </P> <P> The kinetochore (/ kɪˈnɛtəkɔər /, / - ˈniːtəkɔər /) is a protein structure on chromatids where the spindle fibers attach during cell division to pull sister chromatids apart . Their proteins help to hold the sister chromatids together and also play a role in chromosome editing . </P> <P> The kinetochore forms in eukaryotes, assembles on the centromere and links the chromosome to microtubule polymers from the mitotic spindle during mitosis and meiosis . </P>

What holds the sister chromatids together and attaches them to the spindle fibers