MOLECULAR BIOLOGY OF NEUROTRANSMITTER RECEPTORS

这项计划是为了表征基因和蛋白质的结构和 两种主要神经递质受体的进化 多基因家族。基因家族是那些包含 肾上腺素能、毒碱能、视蛋白、5-羟色胺受体和第二 含有烟碱胆碱能、GABA/苯二氮卓类和 甘氨酸受体。具体目标是克隆和测序 这两个多基因家族中受体的基因；为了获得非常 高密度受体的表达及表达蛋白的利用 用x射线测定这些受体的完整结构 结晶学和计算机增强的分子模拟； 确定神经递质受体基因的进化 家系；寻找和鉴定受体基因 多态现象。到目前为止，我们已经克隆并测序了一个重要的 来自多基因家族的受体基因的数量。这些措施包括 人脑和基因组文库中的β2-肾上腺素能受体 大鼠心脏和大鼠基因组文库和鲨鱼基因组文库。 人类基因组文库中的β1肾上腺素能受体：M1-M4 人、大鼠、鲨鱼和动物的M胆碱能受体 果蝇基因组文库。人α-2肾上腺素能受体 来自人类基因组文库；人类的α和β亚基 人类基因组文库中的GABA/苯二氮卓类受体； 果蝇基因和基因组文库中的肾上腺素能受体 神经细胞cDNA文库和蝗虫的烟碱受体基因 C DNA文库和鸡GABA的基因组克隆 苯二氮卓类受体。这些受体已经克隆到 表达载体和转染的哺乳动物细胞。结果是 是表达独特神经递质的永久性细胞系 受体蛋白。表达的受体系提供了关键 关于受体激活机制的新信息 神经递质和受体结构决定因素的基础。

This project is to characterize the gene and protein structure and evolution of neurotransmitter receptors belonging to two major multi gene families. The gene families are those containing adrenergic, muscarinic, opsin, seratonin receptors and the second family containing nicotinic cholinergic, GABA/benzodiazepine and glycine receptors. The specific aims are to clone and sequence the genes for receptors in these two multigene families; to obtain very high density receptor expression and to use the expressed proteins to determine the complete structure of these receptors by x-ray crystallography and computer enhanced molecular modeling; to determine the evolution of the neurotransmitter receptor gene families; to search for and characterize receptor gene polymorphisms. To date we have cloned and sequenced a significant number of receptor genes from multigene families. These include beta 2-adrenergic receptors from human brain and genomic library, rat cardiac and rat genomic library and from shark genomic library. Beta 1-adrenergic receptors from a human genomic library; M1-M4 muscarinic cholinergic receptors from human, rat, shark and Drosophila genomic library. The human alpha-2 adrenergic receptor from a human genomic library; human alpha and beta subunits of the GABA/benzodiazepine receptor from human genomic libraries; adrenergic receptors from Drosophila cDNA and genomic library; nicotinic receptor genes from neuronal cDNA library and from locust cDNA libraries, and a chick genomic clone of the GABA benzodiazepine receptor. These receptors have been cloned into expression vectors and mammalian cells transfected. The results are permanent cell lines expressing the unique neurotransmitter receptor protein. The expressed receptor lines are providing key new information concerning the mechanism of receptors activated by neurotransmitters and a basis of receptor structural determinants.