本项目对应指南第一部分重点资助研究方向“（一）生物大分子动态修饰的化学标记与检测技术”中“聚焦生物大分子化学修饰的动态属性，发展标记和检测动态化学修饰”的研究重点。.正确的动点与微管连接对于染色体的精确分离至关重要。SET7/9能二甲基化PLK1，还能甲基化修饰PLK1的底物MCAK，但是其维持染色体与微管的动态连结的机制并不明晰。本项目通过构建有效的双FRET荧光探针，同时监测PLK1激酶活性和甲基化修饰水平的时空动态性，进一步解析SET7/9-PLK1-MCAK信号轴调控动点和微管动态连接，阐明两种化学修饰协同影响有丝分裂进程的科学问题。通过本项目的研究，借助荧光探针和有丝分裂化学小分子探针的进一步发掘与应用，将有助于我们系统地解析细胞有丝分裂过程中染色体稳定性维系的详尽信号转导机制及分子动力学规律，阐明翻译后修饰动态互作的意义，为有关疾病的精准干预提供理论基础与平台技术。

This project focuses on ‘Reveal the nature and regulation mechanism of dynamic biomacromolecule modifications via developing chemical labeling and detection methods at the molecular, subcellular and cellular levels’ of the first research funding area ‘Chemical labeling and detection of dynamic modifications of biomacromolecules’. .Faithful segregation of mitotic chromosomes requires bi-orientation of sister chromatids, which relies on the sensing of correct attachments between spindle microtubules and kinetochores. In our study, SET7/9-elicited dimethylation occurs at the Lys191 of PLK1. And the microtubule depolymerase mitotic centromere-associated kinesin (MCAK), a substrate of PLK1, can be methylated by SET7/9. However, we still need some special biosensors for study different dynamic modifications of PLK1. This project focuses on detection of the spatiotemporal dynamics of the phosphorylation and methylation activity of PLK1 kinase by Dual-FRET (Fluorescence resonance energy transfer) biosensor. We aim to define the SET7/9-PLK1-MCAK signaling axis which is essential for stable kinetochore-microtubule attachments, and study the cross-talk of phosphorylation and methylation of PLK1. Taken together, the further exploration and application of the biosensors and chemical small molecule probes of mitotic proteins will help us to systematically analyze the mechanism of signaling pathways and molecular dynamics of chromosome stability maintenance in mitosis, and facilitate improved understanding of dynamic post-translational modifications cross-talk for precision medicine.