Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan.
Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan.
Curr Opin Cell Biol. 2018 Jun;52:73-81. doi: 10.1016/j.ceb.2018.02.005. Epub 2018 Feb 21.
Faithful chromosome segregation during mitosis in eukaryotes requires a large protein complex, kinetochore, formed on the centromere of each chromosome, to attach to spindle microtubules. Among the kinetochore proteins, Constitutive Centromere-Associated Network (CCAN) and KMN-network proteins form the base of the vertebrate kinetochore architecture. The CCAN proteins constitutively localize to the centromere throughout the cell cycle, whereas KMN-network proteins are recruited to the CCAN only during mitosis. Recent studies in cellular and structural biology, as well as biochemical reconstitutions, have revealed that mitotic phosphorylation of kinetochore proteins has critical roles in kinetochore organization. Here, we discuss the molecular processes of kinetochore assembly during mitotic entry and its disassembly during mitotic exit.
有丝分裂过程中，真核生物的染色体分离需要一个由着丝粒上的大量蛋白质组成的复合物——动粒，来与纺锤体微管结合。在动粒蛋白中，组成性着丝粒相关网络（CCAN）和 KMN 网络蛋白构成了脊椎动物动粒结构的基础。CCAN 蛋白在整个细胞周期中都持续定位于着丝粒，而 KMN 网络蛋白仅在有丝分裂时被招募到 CCAN。细胞和结构生物学以及生化重建的最新研究表明，动粒蛋白的有丝分裂磷酸化在动粒组织中起着关键作用。在这里，我们讨论了有丝分裂进入时动粒组装的分子过程及其在有丝分裂退出时的解体。
