Characterizing exon 11 promoter of the mu opioid receptor gene, OPRM

描述（由申请人提供）：本提案的长期目标是了解μ阿片受体（Oprm）基因的调节机制，并深入了解该调节的药理学和生理学意义。早期的药理学研究已经提出了几种μ阿片受体亚型：μ 1，μ 2和吗啡-62-葡糖苷酸（M6 G）。然而，仅鉴定出一个μ阿片受体基因，这增加了替代前mRNA剪接和Oprm基因的多个启动子可能导致多种μ阿片受体的可能性。在过去的十年中，我们已经确定了25个剪接变异体从小鼠Oprm基因，13个剪接变异体从大鼠Oprm基因和12个从人类Oprm基因。剪接变体的功能意义由区域和细胞特异性表达、激动剂诱导的G蛋白偶联和受体内化的差异支持。通过分离一个新的启动子，外显子11启动子（E11启动子），进一步证明了Oprm基因的多样性。E11相关变体和E11启动子的保守性也已通过在大鼠和人Oprm基因中鉴定这些小鼠同源物而得到证实。我们最近的敲入/敲除研究表明，在小鼠缺乏外显子11，M6 G，6-乙酰吗啡和海洛因镇痛大大减少，而吗啡的反应保持不变，这意味着外显子11相关的剪接变异体和外显子11启动子介导的一个子集的μ阿片类药物的行动的主要功能作用。本提案将继续探讨E11发起人的规定和功能，并提出以下具体目标：1）。鉴定小鼠E11启动子; 2）.研究人E11启动子的结构和功能; 3）.利用双基因打靶小鼠模型研究E11和E1启动子的药理学功能。本研究将有助于我们更好地理解Oprm基因调控的复杂性和功能重要性，建立研究Oprm基因调控和功能的基因靶向动物模型，并为开发新型镇痛药物和药物滥用药物提供潜在靶点。本研究的主要目的是进一步研究μ阿片受体（Oprm）基因外显子11启动子的调控和功能。本研究将有助于我们更好地理解Oprm基因调控的复杂性和功能重要性，建立研究Oprm基因调控和功能的基因靶向动物模型，并为开发新型镇痛药物和药物滥用药物提供潜在靶点。

DESCRIPTION (provided by applicant): The long term goal of this proposal is to understand the mechanisms by which the mu opioid receptor (Oprm) gene is regulated and to gain insights into the pharmacological and physiological significance of this regulation. Early pharmacological studies have proposed several mu opioid receptor subtypes: mu1, mu2 and morphine-62-glucuronide (M6G). However, only one mu opioid receptor gene has been identified, raising the possibility that alternative pre-mRNA splicing and multiple promoters of the Oprm gene may be responsible for the multiple mu opioid receptors. Over the last ten years, we have identified 25 splice variants from the mouse Oprm gene, 13 splice variants from the rat Oprm gene and 12 from the human Oprm gene. The functional significance of the splice variants is supported by differences in regional and cell-specific expression, agonist-induced G protein coupling and receptor internalization. Diversity of the Oprm gene was further demonstrated by isolation of a new promoter, exon 11 promoter (E11 promoter). Conservation of the E11-associated variants and the E11 promoter has also been confirmed by identifying these mouse homologs in the rat and human Oprm genes. Our recent knockin/knockout study showed that in mice lacking exon 11, M6G, 6-acetylmorphine and heroin analgesia were greatly diminished, while morphine's response remained unchanged, implying a major functional role for exon 11-associated splice variants and exon 11 promoter in mediating the actions of a subset of mu opioids. This proposal will continue to explore the regulations and functions of E11 promoters by proposing the following specific aims: 1). To characterize the mouse E11 promoter; 2). To investigate structure and function of the human E11 promoter; 3). To explore the pharmacological function of E11 and E1 promoters using double gene targeting mouse model. The knowledge gained from this proposal will help us obtain a better understanding of the complexity and functional importance of Oprm gene regulation, establish the gene targeted animal models for studying the underlying mechanisms of this gene regulation and function, and provide potential targets for developing novel drugs used in control of pain and drug of abuse. The primary goal of this proposal is to further investigate the regulations and functions of a new promoter, exon 11 promoter, in the mu opioid receptor (Oprm) gene. The knowledge gained from this proposal will help us obtain a better understanding of the complexity and functional importance of Oprm gene regulation, establish the gene targeted animal models for studying the underlying mechanisms of this gene regulation and function, and provide potential targets for developing novel drugs used in control of pain and drug of abuse.