Small molecule stabilizers of RGS protein expression

RGS蛋白表达的小分子稳定剂

• 批准号: 8894023
• 负责人: RICHARD R NEUBIG
• 金额: $ 34.05万
• 依托单位: MICHIGAN STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-01 至 2017-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8894023
• 关键词: Anxiety; Attention; Binding; Biological; Biological Assay; Biological Process; Biology; Blood Vessels; Bortezomib; Brain; Cancer Biology; Cardiovascular Pathology; Cardiovascular system; Cells; Chemicals; Communication; Complex; Cullin Proteins; Degradation Pathway; Disease; Docking; Drug Targeting; Enhancers; Enzymes; Family; G-Protein-Coupled Receptors; GTP-Binding Protein Regulators; Genetic Polymorphism; Genetic study; Goals; Haplotypes; Health; Heart; Heart failure; Human; Human Genetics; Hypertension; In Vitro; Kidney; Knockout Mice; Lead; Ligase; Link; Malignant - descriptor; Malignant Neoplasms; Mediating; Mental disorders; Messenger RNA; Modeling; Molecular Machines; Outcome Study; Panic Disorder; Pathway interactions; Patients; Phenotype; Play; Proteasome Inhibitor; Proteins; RGS Proteins; RGS2 gene; RGS4 protein; RNA Interference; Regulation; Role; Sampling; Schizophrenia; Series; Signal Transduction; Site; Smooth Muscle Myocytes; Specificity; Spottings; Structure; Structure-Activity Relationship; System; Testing; Ubiquitin; Up-Regulation; Work; androgen independent prostate cancer; base; cancer therapy; design; falls; feeding; high throughput screening; in vivo; inhibitor/antagonist; interest; malignant breast neoplasm; member; multicatalytic endopeptidase complex; neuropsychiatry; novel; pro-apoptotic protein; protein degradation; protein expression; protein function; protein protein interaction; screening; small molecule; success; ubiquitin-protein ligase; virtual

DESCRIPTION: Tremendous advances have been made in the rational design of inhibitors of many biological processes including protein-protein interactions. However it is often desirable to increase the activity of a protein. Blocking negative regulation pathways is an alternative to directly targeting the protein of interest. The ubiquitin- proteasome mechanism is a key regulator of protein function through rapid and controlled degradation but current proteasome inhibitors have low specificity. With over 600 distinct E3 ubiquitin ligases there is potential for great specificity in targeting protein degradation. As a model to define strategies for selective pharmacological targeting of protein degradation, we will study two Regulator of G protein Signaling proteins, RGS2 and RGS4 that are degraded by different E3 ligase mechanisms. Reduced RGS2 expression is seen in cardiovascular pathologies (hypertension and heart failure) and also plays a role in anxiety and cancer biology. RGS4 has been implicated in heart failure and low levels have been found in brains of schizophrenia patients and in aggressive human breast cancer lines. Thus increasing RGS2 or 4 expressions could have broad pharmacological ramifications. RGS4 is degraded by a single-chain N-end rule E3 ligase mechanism. We recently found that RGS2 degradation utilizes the distinct Cullin-Ring-Ligase E3 mechanism. The complexities and regulation of ubiquitin-proteasome molecular machines make it hard to predict exactly where the druggable "soft-spots" are likely to be, so broad screening approaches provide a way to detect novel sites of action. By comparing RGS2 and RGS4 regulation, we will explore mechanisms and specificity in E3 targeting. Using a robust, HTS- compatible, cell-based assay to detect RGS2 or RGS4 protein levels we will: 1) identify small molecule enhancers of RGS cellular expression, 2) examine the specificity of their actions in counter- screens, 3) obtain initial structure-activity relationships with commercially available compounds and 4) assess compound mechanisms of action by defining the role of direct compound binding to RGS proteins or to the relevant E3 ligase components. The long term goal of this work is to define strategies for the selective pharmacological targeting of protein degradation. Successful completion of this work will provide mechanistically characterized compound series that enhance RGS2 and RGS4 protein expression and function. Such compounds will serve as chemical probes of protein degradation that would illuminate effects of RGS upregulation in biology and in neuropsychiatric, cardiovascular, and malignant diseases.

描述：在合理设计包括蛋白质-蛋白质相互作用在内的许多生物过程的抑制剂方面取得了巨大的进展。然而，通常需要增加蛋白质的活性。阻断负调控途径是直接靶向感兴趣蛋白的一种替代方法。泛素-蛋白酶体机制是通过快速和可控的降解来调节蛋白质功能的关键机制，但目前的蛋白酶体抑制剂特异性较低。有超过600种不同的E3泛素连接酶，在靶向蛋白质降解方面具有很大的特异性。作为确定蛋白质降解选择性药理靶向策略的模型，我们将研究两种G蛋白信号调节蛋白RGS2和RGS4，它们被不同的E3连接酶机制降解。RGS2的表达减少在心血管疾病（高血压和心力衰竭）中可见，并在焦虑和癌症生物学中发挥作用。RGS4与心力衰竭有关，在精神分裂症患者和侵袭性人类乳腺癌系的大脑中发现了低水平的RGS4。因此，增加RGS2或4的表达可能具有广泛的药理意义。RGS4通过单链n端规则E3连接酶机制降解。我们最近发现RGS2的降解利用独特的Cullin-Ring-Ligase E3机制。泛素-蛋白酶体分子机器的复杂性和可调控性使得很难准确预测可药物“软点”可能在哪里，因此广泛的筛选方法提供了一种检测新作用位点的方法。通过比较RGS2和RGS4的调控，探讨E3靶向的机制和特异性。使用一个强大的，HTS兼容的，基于细胞的检测RGS2或RGS4蛋白水平的方法，我们将：1)鉴定RGS细胞表达的小分子增强子，2)在反筛中检查其作用的特异性，3)获得与市售的初始结构-活性关系