Design, synthesis and functional characteristics of low molecular weight proline-rich motif (PRM) mimetics recognized by PRM binding domains

小分子难以调节蛋白质-蛋白质相互作用(PPI)的一个主要原因是它们通常具有平坦且相当大的结合界面，表现出很小的凹陷性。这些交互作用根据它们的特殊性进行分类。这类蛋白结构域的一个重要部分展示了暴露在溶剂中的区域，这些区域能够结合目标蛋白的富含脯氨酸的基序(PRM)。目前已知PRM结合域(PRO)(Src同源3(SH3)结构域、WW结构域、EVH1(Ena/Vasp同源1)结构域、GYF结构域、UEV(泛素E2变体)结构域和Profilin六个不同的家族。在许多多组分的信号复合体中，这类PRD通过堆积在其表面的芳香氨基酸识别Pro残基的特征模式。此外，这种相互作用的特异性受到侧翼结合表位的影响。该项目的目的是发现人类EVH1结构域、src激酶Fyn的SH3-结构域和YAP-WW结构域的新的特定调节子，基于在前一个项目阶段开发和表征的新的多聚脯氨酸II螺旋模拟结构和结构修饰。这些化合物代表了PrM模拟的一个新领域，并可能作为äS开发特定的、药理上相关的PrM介导的蛋白质-蛋白质相互作用(PPI)抑制剂的起点。此外，我们通过筛选ChemBioNet文库和虚拟筛选特定组装的焦点文库来寻找新的先导化合物来调节这三个结构域家族。该项目结合了合理的、基于结构的小分子设计、结构生物学、新型支架的立体选择性合成、肽合成、新的支架连接策略、化合物筛选和前体调节剂的功能表征。

A major reason for the difficulty in modulating protein-protein interactions (PPI) by small molecules is that they typically possess flat and rather large binding interfaces, displaying little concavity. These interactions are classified according to their specificity. An important dass of such protein domains exhibits solvent exposed regions that are able to bind the proline-rich motifs (PRM) of their target proteins. Currently, six distinct families of PRM-binding domains (PRO) (Src-homology 3 (SH3) domains, WW domains, EVH1 (Ena/VASP homology 1) domains, GYF domains, UEV (ubiquitin E2 variant) domains and profilin are known. Present in many multi-component signaling complexes, such PRDs recognize characteristic patterns of proline residues by means of stacked aromatic amino acids on their surface. Additionally, the specificity of this interaction is influenced by flanking binding epitopes. The aim of this project is to discover new specific modulators of the human EVH1 domain, the SH3-domain of the src kinase Fyn, and the YAP-WW domain, based on a new polyproline II helix mimetic structure and structural modifications developed and characterized during the previous project phase. These compounds represent a new dass of PRM mimetics and may serve äs starting points for the development of specific, pharmacologically relevant inhibitors of PRM- mediated protein-protein interaction (PPI). Additionally, we search for new lead compounds to modulate the three families of domain by screening the ChemBioNet library and by virtual screening of specifically assembled focused libraries. The project combines rational, structurebased small molecule design, structural biology, stereoselective synthesis of novel scaffolds, peptide synthesis, new scaffold-based ligation strategies, compound screening and functional characterization of the PRO modulators.