Selective Targeting of G Protein beta gamma Subunits with Small Molecules

描述（由申请人提供）：G蛋白23亚基在G蛋白偶联受体（GPCR）介导的信号转导中起核心作用。它们在受体介导的激活过程中作为辅因子，并在向下游靶点的信号传递中发挥直接作用。在许多系统中积累了大量数据，表明过量的23信号传导具有病理后果，并且操纵23亚基信号传导可能是心力衰竭以及其他疾病的有效治疗策略。我们已经开发了一种新的靶向策略，选择性地操纵G蛋白23亚基信号通路，通过选择性地阻断23-亚基与功能蛋白质伴侣的结合相互作用，使用小分子。在我们的初步数据中，我们证明这些化合物在心力衰竭、炎症和吗啡依赖性镇痛的动物模型中是有效的。在拟议的实验中，我们将探讨这23种结合化合物的结合和选择性的基本机制。在具体目标1中，实验将表征化合物对广泛的G23靶标的选择性，并开发用于预测化合物选择性的新测定法。具体目标2将结合联合收割机生物物理配体相互作用的方法，诱变和x射线晶体学，以发展一个详细的了解机制的选择性。具体目标3将利用具体目标2的信息来完善我们的计算筛选方法，以更有效地鉴定可能具有独特作用机制的化合物。具体目标4将应用我们对中性粒细胞功能中GPCR信号传导的选择性的知识。成功完成所提出的实验将导致对靶向G23信号传导的新分子家族的作用机制的透彻理解，所述新分子家族在剖析GPCR刺激的信号传导的作用机制中具有潜在用途，并为新的治疗方法提供基础。G蛋白偶联受体（GPCR）是负责识别一大类不同配体的主要类型的跨膜受体。在这里，我们提出了在我们的实验室中鉴定的G蛋白23亚基的选择性小分子抑制剂的研究，其可用于抑制多种GPCR并修改现有GPCR定向药物的作用。 公共卫生相关性：这些实验的结果将有助于验证这种替代方法，以修饰GPCR下游的信号传导途径，最终可能导致新疗法的开发。

DESCRIPTION (provided by applicant): G proteins 23 subunits play a central role in G-protein coupled receptor (GPCR)- mediated signal transduction. They act as cofactors in the receptor-mediated activation process as well as playing direct roles in signal transfer to downstream targets. Considerable data has accumulated in number of systems that excess 23 signaling has pathological consequences and that manipulation of 23 subunit signaling could be an effective therapeutic strategy in heart failure as well as other diseases. We have developed a novel targeting strategy for selective manipulation of G protein 23 subunit signaling pathways by selectively blocking 23-subunit binding interactions with functional protein partners using small molecules. In our preliminary data we demonstrate these compounds are efficacious in animal models of heart failure, inflammation and morphine-dependent analgesia. In the proposed experiments we will explore the fundamental mechanisms underlying binding and selectivity of these 23 binding compounds. In Specific aim 1 the experiments will characterize the selectivity of compounds for a broad range of G23 targets and develop new assays for predicting compound selectivity. Specific aim 2 will combine biophysical ligand interaction methods, mutagenesis and x-ray crystallography to develop a detailed understanding of the mechanisms for selectivity. Specific aim3 will exploit the information from specific aim 2 to refine our computational screening approach to allow for more efficient compound identification that may have unique mechanisms of action. Specific aim 4 will apply our knowledge of selectivity to GPCR signaling in neutrophil functions. Successful completion of the proposed experiments will lead to a thorough understanding of a the mechanism of action of a new family of molecules that target G23 signaling that have potential uses in dissecting the mechanisms of action of GPCR stimulated signaling and providing the basis for novel therapeutic approaches. G protein coupled receptors (GPCRs) are a major class of transmembrane receptors responsible for recognition of a large class of diverse ligands. Here we propose investigation of selective small molecule inhibitors of G protein 23 subunits identified in our laboratory which could be used to inhibit multiple GPCRs and modify actions of existing GPCR directed pharmaceuticals. Public Health Relevance: Results of these experiments will help to validate this alternate approach to modification of signaling pathways downstream of GPCRs that could ultimately lead to development of novel therapeutics.