Development of photoaffinity ligands for the alpha3beta4 nicotinic acetylcholine

α3β4烟碱乙酰胆碱光亲和配体的开发

• 批准号: 7574002
• 负责人: FAMING JIANG
• 金额: $ 25.14万
• 依托单位: SRI INTERNATIONAL
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-02-01 至 2011-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7574002
• 关键词: Absence of pain sensation; Acetylcholine; Active Sites; Affinity; Agonist; Alzheimer' s Disease; Arousal; Benzophenones; Binding; Binding Sites; Biology; Biopolymers; DNA; Development; Diazomethane; Drug Addiction; Epilepsy; Goals; In Vitro; Ion Channel; Laboratories; Lead; Learning; Ligand Binding; Ligands; Literature; Maps; Memory; Neuraxis; Neurodegenerative Disorders; Neurons; Nicotinic Receptors; Pain; Parkinson Disease; Pharmaceutical Chemistry; Pharmacology; Photoaffinity Labels; Physiological; Play; Process; Property; Proteins; Reader; Receptor Activation; Reporting; Research; Resistance; Rewards; Role; Sequence Homology; Series; Structure; Structure-Activity Relationship; Testing; analog; base; cognitive function; covalent bond; design; epibatidine; fluorescence imaging; motor control; novel; photoactivation; prototype; public health relevance; receptor; tool; tool development

DESCRIPTION (provided by applicant): The nicotinic acetylcholine receptors (nAChRs) are pentameric ligand-gated excitatory ion channels located in the central nervous system (CNS) and periphery. The nAChRs comrpise various combinations of 1 and 2 subunits that form hetero- or homomeric combinations. The neuronal nAChRs play a role in a number of processes connected to cognitive function, learning and memory, arousal, reward, motor control, and analgesia. Subtype-selective nAChR ligands offer potential for treatment of numerous pathophysiological conditions including drug addiction, pain, epilepsy, and neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. The pharmacology of these receptors is not yet thoroughly understood. Although extensive series of nAChR ligands have been reported, rational design of subtype-selective agonists and antagonists has been difficult. For the 1324 nAChR in particular, no truly selective ligands are available. This situation can be attributed mainly to inadequate structural information on the receptor subtypes and their binding sites, the high sequence homology among the subunits that form the nAChRs, and a lack of subtype- selective ligands. Photoaffinity labeling (PAL) has been a powerful approach for identifying subunits and mapping the active sites of biopolymers such as DNA and protein molecules, and it enables the direct probing of a target protein through a covalent bond photochemically introduced between a ligand and its specific receptor. Our laboratory has recently identified several potent 1324-selective ligands that have low nanomolar affinity and very high selectivity for 1324 versus 1422 subtype. The high selectivity of these ligands for the 1324 receptor makes them ideal leads for development of tools to define the structural basis of subtype selectivity and to understand the role of 1324 nAChR in conditions in which 1324 nAChR is involved, such as drug addiction. The goal of the research is to develop PAL ligands for the 1324 nAChR subtype. Development of suitable PAL ligands will provide useful tools to elucidate the ligand-receptor interactions and provide information on structure of the receptor and its bioactive pocket. The specific aims are to use SAR studies and medicinal chemistry to develop potential 1324-selective PAL ligands using our lead compounds as a prototype; use in vitro pharmacology to characterize binding and functional properties of novel ligands; and determine if photoactivation leads to irreversible (wash-resistant) binding and irreversible inhibition of receptor activation. PUBLIC HEALTH RELEVANCE: The 1324 nicotinic acetylcholine receptor (nAChR) has been shown to play a role in drug addiction. However, its biology and pharmacology are not yet thoroughly understood. The basis of subtype selectivity for nAChR ligands is also not well-understood. This proposed project will develop 1324 photoaffinity ligands based on our recently discovered selective and potent lead compounds. These photoaffinity ligands will be useful tools to understand the structural basis of selectivity and rational design of 1324 nAChR for the treatment of drug addiction.

描述（由申请人提供）：烟碱乙酰胆碱受体（nAChR）是位于中枢神经系统（CNS）和外周的五聚体配体门控兴奋性离子通道。 nAChR包含形成异聚或同聚组合的1和2个亚基的各种组合。神经元 nAChR 在与认知功能、学习和记忆、唤醒、奖励、运动控制和镇痛相关的许多过程中发挥作用。亚型选择性 nAChR 配体为治疗多种病理生理病症提供了潜力，包括药物成瘾、疼痛、癫痫和神经退行性疾病，如阿尔茨海默病和帕金森病。这些受体的药理学尚未完全了解。尽管已经报道了广泛的nAChR配体系列，但亚型选择性激动剂和拮抗剂的合理设计仍然很困难。特别是对于 1324 nAChR，没有真正的选择性配体可用。这种情况主要归因于受体亚型及其结合位点的结构信息不足、形成nAChR的亚基之间的高序列同源性以及缺乏亚型选择性配体。光亲和标记 (PAL) 是一种识别亚基和绘制 DNA 和蛋白质分子等生物聚合物活性位点的强大方法，它能够通过配体与其特定受体之间光化学引入的共价键直接探测目标蛋白质。我们的实验室最近鉴定了几种有效的 1324 选择性配体，它们对 1324 与 1422 亚型具有低纳摩尔亲和力和非常高的选择性。这些配体对 1324 受体的高选择性使其成为开发工具的理想先导，以定义亚型选择性的结构基础并了解 1324 nAChR 在涉及 1324 nAChR 的条件（例如药物成瘾）中的作用。该研究的目标是开发 1324 nAChR 亚型的 PAL 配体。合适的 PAL 配体的开发将为阐明配体-受体相互作用提供有用的工具，并提供有关受体结构及其生物活性袋的信息。具体目标是利用 SAR 研究和药物化学，以我们的先导化合物为原型，开发潜在的 1324 选择性 PAL 配体；利用体外药理学来表征新型配体的结合和功能特性；并确定光活化是否导致不可逆（耐洗）结合和受体激活的不可逆抑制。公共卫生相关性：1324 烟碱乙酰胆碱受体 (nAChR) 已被证明在药物成瘾中发挥作用。然而，其生物学和药理学尚未完全了解。 nAChR 配体亚型选择性的基础也不太清楚。该拟议项目将基于我们最近发现的选择性和有效的先导化合物开发 1324 个光亲和配体。这些光亲和配体将成为了解 1324 nAChR 治疗药物成瘾的选择性和合理设计的结构基础的有用工具。