面向蛋白甲基化的智能富集新材料

Protein methylation is one of the most common and important post-translational modification types, which plays essential roles in epigenetic regulation. However, owing to the diversity of protein methylation, ultra-low abundance and the inherent complexity of biosamples, it is extremely difficult to capture, analysis and identify the methylation sites at the level of proteomics. Thus, developing high-efficiency enrichment materials and corresponding methods capable of capturing various types of methylated peptides is highly urgent, which could not be resolved by artificial materials by far. In this project, we innovatively introduce the design idea of biomolecule-responsive polymer to tackle the challenges of methylated peptide enrichment and separation. By mimicking the peptide sequences and the unique conformation of binding domains in methylation site-specific binding proteins, the optimized oligopeptide sequences could be designed for recognizing the methylation sites precisely. In addition, these oligopeptides would be copolymerized with diverse functional monomers to prepare smart polymer-based enrichment materials. Then dynamic adsorption or desorption behaviours of methylated peptides on these smart polymer surfaces could be modulated by various chromatographic conditions, such as solvent polarity, solution pH, temperature or ionic strength. Based on these researches, the optimized enrichment methodology could be built reasonably, and the enrichment efficiency of our materials towards methylated peptides will be evaluated in model histone protein, cell and tissue samples. The remarkable advantages of smart polymers in high binding affinity, satisfactory selectivity, good controllability, easy elution and expandable material platform, provide a new insight for the development of methylated peptide enrichment materials.

蛋白甲基化是最常见的翻译后修饰方式之一，在表观遗传调控中发挥着至关重要的作用。然而，甲基化形式的多样性、低丰度和生物样品的复杂性，导致在蛋白质组学水平上捕获、分析、鉴定甲基化位点非常困难。因此，急需开发对各种类型的甲基化肽链具有高效捕获能力的人工材料和富集方法。在本项目中，申请人创新地利用生物分子响应性聚合物的设计思想，尝试解决甲基化肽链的富集和分离挑战。借助模仿甲基化位点结合蛋白结构域中的氨基酸序列，构筑合适的短肽，实现对甲基化肽的精确识别。进而将这些短肽与各种功能单体共聚，制备智能聚合物材料。通过调节溶剂极性、温度、pH值、离子强度等参数，实现甲基化肽段在聚合物表面上动态可调的吸附、脱附过程。在此基础上建立富集方法学，评估材料在组蛋白模型样品、细胞、组织样本中对甲基化肽的富集性能。智能聚合物结合力强、选择性高、可控性好、易洗脱、易扩展等特点，将为甲基化肽富集材料的开发提供一种新的思路。

面向翻译后修饰蛋白质组学富集材料的研发，生物分子调控的纳米离子通道器件，以及新型传感探针的发现。在翻译后修饰蛋白质组学富集领域，研究内容包括系统总结了智能生物分离材料的研究进展，创新性地提出了基于动态共价化学的唾液酸糖链捕获新策略，设计了基于二肽的聚合物材料实现了对唾液酸糖链的精确识别，基于氢键的双功能智能聚合物能够同时高效富集磷酸肽和糖肽，利用赖氨酸和18-冠-6之间的选择性络合高效分离甲基化肽与非修饰肽。.此外，研究组将生物分子响应性聚合物与纳米孔道融合起来，开发了一系列生物分子调控的纳米离子通道器件，实现了对多种生物分子的灵敏检测和分析。例如构建了基于纳米离子通道的酪氨酸磷酸化检测器件，能够实时监测酪氨酸激酶催化下的蛋白磷酸化反应；进一步的工作通过逻辑传感平台展现了区分酪氨酸激酶和丝氨酸/苏氨酸激酶以及评估多激酶活性的潜力，能够满足多靶标药物设计的要求。与此同时，完成人还构建了糖链响应型、环磷酸腺苷响应型、Ca2+离子响应型纳米离子通道器件，系统总结了固态纳米孔在生物分子传感检测中的应用进展。在新型发光探针的构建方面，完成人利用Cu2+可逆、可视化地冻结了分子构型，发现一种全新的AIEE分子及B-O和B-N动态共价键，构建了基于纳米晶纤维素的糖识别光学器件，发明了高强度、耐溶剂光子纤维素膜的制备方法。