The kinetochore is essential for faithful chromosome segregation during mitosis. To form a functional kinetochore, constitutive centromere-associated network (CCAN) proteins are assembled on the centromere chromatin that contains the centromere-specific histone CENP-A. CENP-C, a CCAN protein, directly interacts with the CENP-A nucleosome to nucleate the kinetochore structure. As CENP-C is a hub protein for kinetochore assembly, it is critical to address how the CENP-A–CENP-C interaction is regulated during cell cycle progression. To address this question, we investigated the CENP-C C-terminal region, including a conserved CENP-A–binding motif, in both chicken and human cells and found that CDK1-mediated phosphorylation of CENP-C facilitates its binding to CENP-A in vitro and in vivo. We observed that CENP-A binding is involved in CENP-C kinetochore localization during mitosis. We also demonstrate that the CENP-A–CENP-C interaction is critical for long-term viability in human RPE-1 cells. These results provide deeper insights into protein-interaction network plasticity in centromere proteins during cell cycle progression.

中文翻译：

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CDK1介导的CENP-C磷酸化调节CENP-A结合和有丝分裂着丝粒定位

动粒对于有丝分裂过程中染色体的忠实分离至关重要。为了形成功能性着丝粒，组成型着丝粒相关网络 (CCAN) 蛋白在含有着丝粒特异性组蛋白 CENP-A 的着丝粒染色质上组装。CENP-C 是一种 CCAN 蛋白，直接与 CENP-A 核小体相互作用，使动粒结构成核。由于 CENP-C 是着丝粒组装的枢纽蛋白，因此解决细胞周期进程中如何调节 CENP-A-CENP-C 相互作用至关重要。为了解决这个问题，我们研究了鸡和人细胞中的 CENP-C C 末端区域，包括保守的 CENP-A 结合基序，发现 CDK1 介导的 CENP-C 磷酸化促进了其与 CENP-A 的结合体外和体内。我们观察到 CENP-A 结合参与有丝分裂过程中的 CENP-C 着丝粒定位。我们还证明 CENP-A-CENP-C 相互作用对于人类 RPE-1 细胞的长期活力至关重要。这些结果为细胞周期进程中着丝粒蛋白的蛋白质相互作用网络可塑性提供了更深入的见解。