Chemical Proteomics Approach to Discover Novel Small Molecule E3 Ligase recruiters for Targeted Protein degradation (TPD)

化学蛋白质组学方法发现用于靶向蛋白质降解 (TPD) 的新型小分子 E3 连接酶招募剂

基本信息

批准号：
10711249
负责人：
Jaewon Chang
金额：
$ 39.13万
依托单位：
EMORY UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-08-21 至 2028-07-31
项目状态：
未结题

项目摘要

Project Summary Targeted protein degradation (TPD) is an emerging therapeutic modality with the potential to overcome limitations of traditional pharmacological inhibition approaches. TPD uses small molecules (degraders) to hijack the cellular degradation machinery by recruiting E3 ubiquitin ligases to proteins of interest (POI), which would not otherwise be recognized as substrate. Despite the tremendous promise of TPD approach, major bottlenecks still exist, including: 1) ligand discovery against undruggable disease-causing proteins. 2) a dearth of available E3 ligase recruiters that can be exploited for TPD applications, as there are limited number of E3 ligases, with most of the published degraders using ligands for cereblon and VHL, despite the existence of >600 E3 ligases in the human genome. Therefore, it is a great deal of interest in the discovering of new E3 ligase ligands to expand the scope of new therapeutics. Recently, several research groups discovered cysteine-reactive covalent recruiters against previously untargeted E3 ligases that have been successfully used in TPD by using chemical proteomic approaches. While targeting cysteines serves as a useful starting point, there is a need to consider other types of chemistry to generate covalent E3 recruiters for targeting new E3 ligases to expand the scope of TPD. One such possibility is to target potential nucleophilic residue, such as lysine, tyrosine, and serine on E3 ligases, respectively. However, specific biocompatible electrophiles targeting lysines, tyrosine, and serine are largely unexplored for TPD application. The ultimate goal of this proposal is to design, synthesize and validate new E3 ligases ligands that enable the development of novel degraders. To achieve this, we will use a chemoproteomic strategy that leverages broadly reactive, lysine, tyrosine, and serine-directed electrophilic warheads coupled to selective ligands for intracellular proteins (JQ1 for BRD4 or SLF for FKBP12) to screen for heterobifunctional degrader compounds that operate by covalent adduction of E3 ligases. To this end, we have already succeeded in developing a series of compounds to promote ligand-induced protein degradation. These proof-of-concept degraders led to the induced ubiquitination and proteasomal degradation of target proteins. We will perform further chemoproteomic studies to identify the E3 ligase targets of these degraders responsible for the degradation activity. With our novel approaches, we expect to see the repertoire of E3 ligases recruited for targeted protein degradation to be further enriched, paving the way for the next generation of tissue- and disease- specific molecular degraders.

项目概要靶向蛋白质降解（TPD）是一种新兴的治疗方式，有可能克服传统药理学抑制方法的局限性。 TPD利用小分子（降解剂）劫持通过将 E3 泛素连接酶招募到感兴趣的蛋白质 (POI) 来构建细胞降解机制，这将否则不被认为是底物。尽管 TPD 方法前景广阔，但仍存在主要瓶颈仍然存在，包括：1）针对不可成药的致病蛋白的配体发现。 2）可用资源匮乏 E3 连接酶招募器可用于 TPD 应用，因为 E3 连接酶的数量有限，大多数已发表的降解剂使用 cereblon 和 VHL 的配体，尽管存在 > 600 个 E3 连接酶在人类基因组中。因此，人们对发现新的 E3 连接酶配体非常感兴趣。扩大新疗法的范围。最近，几个研究小组发现了半胱氨酸反应性共价键招募人员针对以前未靶向的 E3 连接酶，这些连接酶已通过化学方法成功用于 TPD 蛋白质组学方法。虽然靶向半胱氨酸是一个有用的起点，但需要考虑其他类型的化学反应生成共价 E3 募集剂，用于靶向新的 E3 连接酶以扩大范围 TPD。其中一种可能性是针对 E3 上潜在的亲核残基，例如赖氨酸、酪氨酸和丝氨酸分别连接酶。然而，针对赖氨酸、酪氨酸和丝氨酸的特定生物相容性亲电子试剂是 TPD 应用很大程度上尚未探索。该提案的最终目标是设计、综合和验证新的 E3 连接酶配体能够开发新型降解剂。为了实现这一点，我们将使用利用广泛反应性的赖氨酸、酪氨酸和丝氨酸定向亲电子的化学蛋白质组策略弹头与细胞内蛋白的选择性配体（BRD4 的 JQ1 或 FKBP12 的 SLF）偶联，以筛选通过 E3 连接酶的共价加合起作用的异双功能降解剂化合物。为此，我们有已经成功开发了一系列化合物来促进配体诱导的蛋白质降解。这些概念验证降解剂导致靶蛋白诱导泛素化和蛋白酶体降解。我们将进行进一步的化学蛋白质组学研究，以确定这些降解剂的 E3 连接酶靶点降解活性。通过我们的新颖方法，我们期望看到 E3 连接酶的库被招募用于靶向蛋白质降解进一步丰富，为下一代组织和疾病铺平道路特定的分子降解剂。