有丝分裂的错误会产生非整倍体子细胞，危害个体发育与健康。着丝粒染色质与动粒的正确组装则是有丝分裂精准完成的前提。内层动粒即CCAN网络为外层动粒的组装提供结构基础，同时也调控了着丝粒的稳定遗传。因此，阐明CCAN的功能与组装具有重要科学意义。CENP-L-N是CCAN的一个亚复合物，其功能和动粒定位机制仍尚未被阐明。我们拟利用knock-in/out细胞系/RNA干扰与成像技术相结合的手段研究CENP-L-N复合物的有丝分裂功能，阐明CENP-L-N如何促进染色体排列和染色体震荡。我们将利用多种生化手段阐明CENP-L-N和其他CCAN组分特别是CENP-H-I-K-M复合物相结合的分子基础和生理意义。我们还将解析在细胞周期中CENP-N在动粒动态定位的动力学特征，探究CENP-N的翻译后修饰及其功能。通过本项目的实施，我们预期研究结果将增进对动粒的功能与动态组装的认识。

The failure of faithful chromosome segregation during mitosis will generate aneuploidy daughter cells and chromosomal instability (CIN). CIN will drive aggressive tumorigenesis by allowing tumor to evolve rapidly and acquire malignant transformation ability. The accurate assembly of centromere chromatin and kinetochore is the prerequisite of faithful mitotic progression. Inner kinetochore, also called constitutive centromere associated network (CCAN), provide structural basis for the assembly of outer kinetochore. Moreover, CCAN also plays a function in the CENP-A centromere deposition (centromere identity maintenance). Therefore, elaborating the function and assembly of CCAN is of great value to promote the health of human being. CENP-L-N is a key subcomplex of CCAN. However, the detailed function and molecular mechanism of CENP-L-N remain poorly understood. In this proposal, we aim to explore the function of CENP-L-N in chromosome alignment and chromosome oscillation using the combination of knock-out cell line, knock-in cell line and RNAi. We will explore the biochemical basis of cross-talk between CENP-L-N and CENP-H-I-K-M by multiple biochemical study methods and will also address physiological function of interaction of CENP-L-N with CENP-H-I-K-M. Through the establishment of SNAP-tag cell line, we will dissect the dynamic centromere deposition of CENP-N in cell cycle using biophotonics methods. Last, we also aim to identify the post-translational modification (PTM) of CENP-N and explore the function of key PTMs. Overall; we aim to address the function of CENP-L-N in accurate mitosis and its role in CCAN assembly plasticity. We hope our research will provide novel knowledge for the elucidation of function and assembly of centromere/kinetochore.