THE MOLECULAR BIOLOGY OF THE MAMMALIAN GRP GENE FAMILY

哺乳动物胃泌素前体的结构、功能和表达 对释放肽(GRP)基因进行了研究。实验是 A)描述结构和规则 大鼠前GRP基因，b)过表达人GRP前激素 分析翻译后加工和多肽的蛋白质 激素功能，c)获得其他蛙素家族的cdna克隆 激素原基因。 A.大鼠前原GRP基因。结构和全核苷酸 用基因组学方法测定了大鼠GRP前原基因的序列 从大鼠脑cdna文库中分离的克隆和cdna克隆。在……里面 与人类基因相比，没有可供选择的RNA加工 在表达该基因的大鼠组织中观察到。编码区 因为GRP及其相关肽在进化上是保守的， 与这两个区域的生物功能一致。大鼠GRP 基因是从大脑中的组织特异性启动子转录而来的， 创造了一条调控基因表达的替代途径。这个 脑特异性启动子仅在大鼠选定的核团中使用 用原位杂交法在细胞水平上分析大脑。 B.人的前原grp基因成功地在 新型杆状病毒蛋白表达系统。使用此模型 系统，可以产生足够的蛋白质来分析 需要生成转换后处理事件 生物活性多肽，并提纯这些多肽以 确立职能。 C.我们设计并合成了共识寡核苷酸 受体结合生物活性的特异性探针 蛙皮素家族多肽的羧基七肽。这 目前正在使用寡核苷酸探针来获得和 神经中表达的其他蛙毒蛋白家族基因的特征 组织。

The structure, function, and expression of mammalian prepro gastrin releasing peptide (GRP) gene was studied. Experiments were performed to a) characterize the structure and regulation of the rat prepro GRP gene, b) overexpress the human GRP prohormone protein to analyze post-translational processing and peptide hormone function, c) obtain cDNA clones for other bombesin family prohormone genes. A. Rat prepro GRP gene. The structure and entire nucleotide sequence of the rat prepro GRP gene was determined, using genomic clones and cDNA clones isolated from a rat brain cDNA library. In contrast to the human gene, there is no alternative RNA processing observed in rat tissues expressing this gene. The coding regions for GRP and its associated peptide are evolutionarily conserved, consistent with a biologic function for both domains. The rat GRP gene is transcribed from a tissue specific promoter in the brain, creating an alternative route for regulating gene expression. The brain specific promoter is used only in selected nuclei in the rat brain when analyzed at the cellular level by in situ hybridization. B. The human prepro GRP gene was successfully overexpressed in a novel baculovirus protein expression system. Using this model system, sufficient protein can be produced to allow analysis of post-translational processing events needed to generate biologically active peptides, and purify those peptides to establish function. C. We have designed and synthesized consensus oligonucleotide probes specific for the receptor-binding biologically active carboxyl heptapeptide of bombesin family peptides. This oligonucleotide probe is currently being used to obtain and characterize other bombesin family genes expressed in neural tissue.