Screening of ligand binding sites of a G-protein coupled receptors by using photocrosslinking

使用光交联筛选 G 蛋白偶联受体的配体结合位点

• 批准号: 113950207
• 负责人: Professorin Dr. Irene Coin
• 金额: --
• 依托单位: Biodesign Institute
• 依托单位国家: 德国
• 项目类别: Research Fellowships
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2010-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/113950207?language=en
• 关键词: Screening; ligand; binding; sites; protein

Most of the pharmaceuticals target G-protein-coupled receptors (GPCRs), which can generally activate different signaling events. Recently developed polypeptide ligands of the corticotropinreleasing factor (CRF) receptor behaved as agonists and, at the same time, antagonists for the activation of different G-proteins. This finding implies significant differences between active conformations of the receptor and probably different ligand binding sites when coupled to different Gproteins. The structure-based development of signaling-selective ligands can result in a new type of drug candidates, but is hampered by a lack of high-resolution structures of GPCRs. We will use methods for site-directed incorporation of a photo-activatable amino acid (Bpa) into proteins to prepare a set of CRF receptor mutants bearing Bpa at various positions relevant for ligand binding. This will allow comparing ligands showing different selectivity for activation pathways with respect to their distinct binding sites. In course of this, we will find out whether Bpa-labeling of the receptor can confirm former results obtained with Bpa-labeled ligands, and we will verify the speculative ligand binding model for the CRF receptor, which is considered as common model for class B GPCRs.

大多数药物靶向g蛋白偶联受体（gpcr），它通常可以激活不同的信号事件。近年来开发的促肾上腺皮质激素释放因子（CRF）受体多肽配体可作为不同g蛋白的激动剂和拮抗剂。这一发现表明，当与不同的g蛋白偶联时，受体的活性构象和可能不同的配体结合位点之间存在显著差异。基于结构的信号选择配体的发展可以产生一种新型的候选药物，但由于缺乏高分辨率的gpcr结构而受到阻碍。我们将使用将光活化氨基酸（Bpa）定向结合到蛋白质中的方法，制备一组在与配体结合相关的不同位置上携带Bpa的CRF受体突变体。这将允许比较相对于其不同的结合位点显示不同选择性的激活途径的配体。在此过程中，我们将验证受体的bpa标记是否可以证实先前用bpa标记的配体得到的结果，并验证CRF受体的推测配体结合模型，该模型被认为是B类gpcr的常用模型。