A small molecule approach to spatial and temporal control of covalent protein inhibition in cells

共价修饰蛋白质的小分子是有价值的治疗手段和生物发现的化学探针。例如，广谱反应探针可用于识别蛋白质中可能被小分子靶向的新配体位点，并分析自然界用于调节蛋白质功能的蛋白质修饰。修饰蛋白靶标的共价抑制剂是一类重要且不断发展的药物。然而，这些抑制剂总是“打开”。蛋白质在细胞中的构象、修饰和位置是生物功能的关键决定因素，本项目的目标是开发一种共价抑制剂，可以在细胞中开启，以研究蛋白质在特定位置和特定时间的生物学特性。该项目将开发化学标记的蛋白质半胱氨酸在细胞中使用共价抑制剂与空间和时间控制。半胱氨酸是共价抑制剂中最常见的靶向残基，也是生物学中涉及氧化还原过程和其他蛋白质修饰的功能残基。我们将笼养半胱氨酸反应性抑制剂，生成可以进入细胞的化合物，然后在我们选择的时间和地点释放这些化合物来标记蛋白质。这种方法将使我们能够克服共价探针潜在的广泛毒性，并控制抑制的时间和位置（例如细胞器或组织）。

Small molecules that covalently modify proteins are valuable therapeutics and chemical probes for biological discovery. For example, broad-spectrum reactive probes can be used to identify new ligandable sites in proteins that could be targeted by small molecules, and to profile protein modifications that nature uses to modulate protein function. Covalent inhibitors that modify a protein target are an important and growing class of drugs. However, these inhibitors are always "on". The conformations, modifications and locations of proteins in cells are key determinants of biological function, and the goal of this project is to develop a covalent inhibitor that can be switched on in the cell to study the biology of a protein in a defined location and at a specific time. This project will develop chemistry to label protein cysteines in cells using covalent inhibitors with spatial and temporal control. Cysteines are the most frequently targeted residue in covalent inhibitors and are functionally interesting residues that are involved in redox processes and other protein modifications in biology. We will cage cysteine-reactive inhibitors, generating compounds that can enter cells and subsequently be uncaged at a time and place of our choosing to label proteins. This approach would allow us to overcome the potential broad toxicity of covalent probes, and control the time and location (e.g. organelle or tissue) of inhibition.