The kinetochore is a complex structure whose function is absolutely essential. Unlike the centromere, the kinetochore at first appeared remarkably well conserved from yeast to humans, especially the microtubule-binding outer kinetochore. However, recent efforts towards biochemical reconstitution of diverse kinetochores challenge the notion of a similarly conserved architecture for the constitutively centromere-associated network of the inner kinetochore. This review briefly summarizes the evidence from comparative genomics for interspecific variability in inner kinetochore composition and focuses on novel biochemical evidence indicating that even homologous inner kinetochore protein complexes are put to different uses in different organisms.

动粒是一个复杂的结构，其功能是绝对必要的。与着丝粒不同，从酵母到人类，动粒起初似乎非常保守，尤其是与微管结合的外动粒。然而，最近对不同动粒的生化重建的努力挑战了内部动粒的组成性着丝粒相关网络的类似保守结构的概念。这篇综述简要总结了比较基因组学中关于内部动粒组成的种间变异性的证据，并着重于新的生化证据，表明即使是同源的内部动粒蛋白复合物在不同的生物体中也有不同的用途。