BIOCHEMICAL CHARACTERIZATION OF OPIOID BINDING SITES

描述：该项目的主要重点是多种阿片受体 结合位点。首席研究员长期以来一直对以下方面感兴趣： 识别阿片受体的多种亚型，使用各种 技术，包括受体结合和镇痛研究。但当 μ阿片受体被克隆，很明显，只有一种类型的受体被克隆。 由mu受体基因编码，并且潜在的多种受体亚型 必须由不同的机制产生。在上一个资助期内， 首席研究员探索了多个μ受体的概念， 产生于μ受体（莫尔-1）基因的可变剪接变体。这些 概念最初来自阿片类镇痛的反义研究，其中 代表莫尔-1不同外显子的不同反义寡核苷酸 基因对镇痛的影响不同。这些研究得到了进一步的发展， 编码许多内含子和外显子的莫尔-1基因的测序。虽然 它们的生理意义尚不清楚，mRNA编码至少 已分离出该受体的12种变体。拟议的研究将 进一步探索这些潜在的受体亚型。第一个具体目标将 提供μ受体剪接变体的详细表征，包括 药理学和解剖学研究以及新克隆的鉴定。的 第二个目标是对ORL-1受体进行类似的实验， 该受体的至少一种新的剪接变体。第三个目标是探索 根据初步的结果，可能存在莫尔-1/ORL-1异二聚体。 发现这两种受体在细胞系中的共表达产生了 结合位点不同于单独的任一位点。第四个目标是 比较OPRL-1的几种肽配体的结合特性 受体的

DESCRIPTION: The principal focus of this project is multiple opioid receptor binding sites. The principal investigator has a long-established interest in identifying multiple subtypes of opioid receptors, using a variety of techniques including receptor binding and analgesia studies. However, when the mu opioid receptor was cloned, it was clear that only one type of receptor was coded by the mu receptor gene, and that potential multiple receptor subtypes must arise from different mechanisms. During the previous funding period, the principal investigator has explored the concept that multiple mu receptors arise from alternative splice variants of the mu receptor (MOR-1) gene. These concepts arose originally from antisense studies of opioid analgesia, in which different antisense oligonucleotides representing different exons of the MOR-1 gene produced different effects on analgesia. The studies were furthered by sequencing of the MOR-1 gene encoding a number of introns and exons. Although their physiological significance is not yet clear, the mRNA coding for at least 12 variants of this receptor have been isolated. The proposed studies will further explore these potential receptor subtypes. The first specific aim will provide a detailed characterization of mu receptor splice variants, including pharmacological and anatomical studies and identification of new clones. The second aim will perform similar experiments on the ORL-1 receptor, identifying at least one novel splice variant of this receptor. The third aim will explore the possible existence of MOR-1/ORL-1 heterodimers, based upon the preliminary finding that co-expression of both of these receptors into cell lines produces binding sites which are different from either site alone. The fourth aim will compare the binding properties of several peptide ligands for the OPRL-1 receptor.