Du Jiayi, Li Shengrong, Xu Fang, Lin Zehong, Hong Tongyi, Li Yifang, Deng Zeyi, Tan Yi, Li Zhengqiu
State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, 601 Huangpu Avenue West, Guangzhou 510632, China.
International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development (MOE), Jinan University, 601 Huangpu Avenue West, Guangzhou 510632, China.
J Med Chem. 2025 Jul 10;68(13):13516-13531. doi: 10.1021/acs.jmedchem.5c00229. Epub 2025 Jun 25.
Covalent probes integrated with chemical proteomics have been an efficient method for disclosing new druggable targets and E3 ubiquitin ligases supporting targeted protein degradation. However, a large fraction of the proteome including E3 ligases remains inaccessible with existing electrophiles. In this work, we developed a new reactive warhead, terminal azoacetylene, which can be generated by in situ desilylation for proteome profiling under cellular conditions. A series of uncharacterized targets and E3 ubiquitin ligases were covalently engaged. Fragment-based ligand discovery (FBLD) showed that the azoacetylene-containing fragments can covalently bind a series of essential protein hits at the active sites such as C130 of TUFM probably modulating the protein functions. Incorporation of this warhead into BRD4 targeting inhibitor JQ1 led to generation of novel small molecular degraders that degrade BRD4 without inducing the hook effect. This provides a new method for ligand and target discovery, as well as the development of new types of small molecular degraders.
与化学蛋白质组学相结合的共价探针一直是揭示新的可成药靶点和支持靶向蛋白质降解的E3泛素连接酶的有效方法。然而，包括E3连接酶在内的很大一部分蛋白质组仍无法用现有的亲电试剂进行研究。在这项工作中，我们开发了一种新的反应弹头——末端偶氮乙炔，它可以通过原位去硅化在细胞条件下生成，用于蛋白质组分析。一系列未被表征的靶点和E3泛素连接酶被共价结合。基于片段的配体发现（FBLD）表明，含偶氮乙炔的片段可以在活性位点共价结合一系列重要的蛋白质靶点，如TUFM的C130，可能会调节蛋白质功能。将这种弹头引入靶向BRD4的抑制剂JQ1中，导致产生了新型小分子降解剂，这些降解剂可以降解BRD4而不诱导钩效应。这为配体和靶点发现以及新型小分子降解剂的开发提供了一种新方法。
