黏连蛋白装载复合体的动粒受体
The Kinetochore Receptor for the Cohesin Loading Complex.
作者信息
Hinshaw Stephen M, Makrantoni Vasso, Harrison Stephen C, Marston Adèle L
机构信息
Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
The Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK.
出版信息
Cell. 2017 Sep 21;171(1):72-84.e13. doi: 10.1016/j.cell.2017.08.017.
The ring-shaped cohesin complex brings together distant DNA domains to maintain, express, and segregate the genome. Establishing specific chromosomal linkages depends on cohesin recruitment to defined loci. One such locus is the budding yeast centromere, which is a paradigm for targeted cohesin loading. The kinetochore, a multiprotein complex that connects centromeres to microtubules, drives the recruitment of high levels of cohesin to link sister chromatids together. We have exploited this system to determine the mechanism of specific cohesin recruitment. We show that phosphorylation of the Ctf19 kinetochore protein by a conserved kinase, DDK, provides a binding site for the Scc2/4 cohesin loading complex, thereby directing cohesin loading to centromeres. A similar mechanism targets cohesin to chromosomes in vertebrates. These findings represent a complete molecular description of targeted cohesin loading, a phenomenon with wide-ranging importance in chromosome segregation and, in multicellular organisms, transcription regulation.
环形黏连蛋白复合体将远距离的DNA结构域聚集在一起,以维持、表达和分离基因组。建立特定的染色体连接依赖于黏连蛋白被招募到特定位点。其中一个这样的位点是芽殖酵母的着丝粒,它是靶向黏连蛋白加载的范例。动粒是一种将着丝粒与微管连接起来的多蛋白复合体,驱动高水平的黏连蛋白被招募,以将姐妹染色单体连接在一起。我们利用这个系统来确定特定黏连蛋白招募的机制。我们发现,保守激酶DDK使动粒蛋白Ctf19磷酸化,为Scc2/4黏连蛋白加载复合体提供了一个结合位点,从而将黏连蛋白加载导向着丝粒。类似的机制将黏连蛋白靶向脊椎动物的染色体。这些发现代表了对靶向黏连蛋白加载的完整分子描述,这一现象在染色体分离以及多细胞生物的转录调控中具有广泛的重要性。