基于均质可溶性糖化终产物受体蛋白的糖基化功能研究

本项目拟开展生物大分子动态修饰的调控机制与功能解析方面的研究，重点关注糖基化修饰在生理病理过程中对蛋白质功能的调控。由于蛋白质糖基化修饰的异质性，要获取含精确糖链结构的蛋白质进行研究仍然充满挑战。人工合成糖蛋白是目前解决糖蛋白微观结构不均一难题、深入研究糖基化修饰功能的重要手段。申请项目将以具有重要生理功能的糖蛋白可溶糖化终产物受体（sRAGE）作为研究对象，发展和运用结合生物表达技术、化学合成及酶催化方法的合成策略，实现这一含320个氨基酸、2个复杂N-糖链的蛋白质的人工合成；获取一系列糖链结构精确、修饰位点确定的蛋白分子，评估不同糖链结构对蛋白质折叠复性效率、稳定性、生物活性等的影响，探索糖基化修饰对sRAGE生理功能的调控机制，并为相关药物发现、改造等研究奠定必要的物质基础。

This proposed project aims to study the functions of post-translational modifications in biological molecules, emphasizing the essential roles of glycosylation in protein-mediated biological and/or pathological processes. Due to the heterogeneity of protein glycosylation in eukaryotic cells, it has been a formidable challenge for obtaining homogeneous glycoproteins. De novo synthesis of glycoproteins is currently a unique and irreplaceable approach toward decoding the functions of glycans based on structurally well-defined glycoforms of proteins. In order to answer the question of glycan functions, this proposal targets an important protein, soluble receptor for glycation end-product (sRAGE), possessing 320 amino acids and two complex-type N-glycans, and describes the proposed synthetic approaches to a series of N-glycosylated sRAGE using biological expression, chemical synthesis, and chemo-enzymatic glycosylation methods. The obtained glycoproteins will be utilized in the evaluation of protein refolding, physicochemical properties, and biological activities. These studies together will be of great value for us to further understand protein glycan functions, and will be beneficial for the development of related drugs and therapeutics.