?1 ADRENERGIC RECEPTOR ACTIVATION & EXPRESSION

-肾上腺素能受体(？-ARs)是一种重要的细胞外信号调节因子。 交感神经控制中枢的各种代谢过程 (中枢神经系统)和周围神经系统。这些受体定位于 神经系统中的多个位置，并作为重要的 中枢神经系统介导的行为和几种神经功能的调节， 包括情绪、记忆、神经内分泌控制和刺激 自主神经功能。我的实验室已经克隆、测序和 表达了大鼠和恒河猴？1肾上腺素能受体基因。我们 已经定义了？1-AR转录起始点，启动子元件， 和多聚腺苷酸化位点在C6胶质瘤细胞中的表达 并确定了潜在的增强子和抑制子区域 这种影响？1-AR表达。我们已经证明了 β1-AR诱导C6细胞内可诱导的cAMP早期抑制因子(ICER) 激动剂，ICER与β1-AR启动子相互作用 下调1-AR基因转录，导致细胞凋亡减少 细胞表面受体。我们还发现，大鼠？1-AR的mRNA 含有两个功能性多聚腺苷酸化位点，而该转录本 异丙肾上腺素诱导的？1-AR对C6细胞的选择作用 MRNA表达下调。这一过程可能受以下因素的影响 转录后调控机制，可能使用 RNA稳定蛋白与富含AU的？1-AR 3‘相互作用 未翻译的区域。目前的研究集中在识别 ？1-AR转录的基因组元件和反式激活子，与 使用？1-AR荧光素酶报告基因重组体，转染实验， DNA迁移率漂移和DNA酶足迹分析。总体着力点 这个项目的目的是准确地识别功能监管 β1-肾上腺素能调节的要素和因素 受体基因，并分析其转录活性。 受体下调和？1-肾上腺素能受体亚型 荷尔蒙刺激。研究将首先利用电子啮齿动物 在使用非人灵长类动物组织之前，在 ？1-AR反式激活子的鉴定。资助NIH HL42358，以及 美国心脏协会设立研究人员奖出版物 李志，Vaidya RVA，Alvaro JD，Iredale PA，Hsu R，Hoffman G，Fitzgerald L，柯伦PK，真田CA，渔民PH，杜曼RS。蛋白激酶 C基因介导的β1-AR基因在大鼠C6胶质瘤中的表达下调 细胞。Mol Pharmacol 54：14-21,1998。杨YF，Kirigiti P，Li B， 德什曼S，加利福尼亚州真田。β1-肾上腺素能受体的差异选择 受体在激动剂诱导下调过程中的转录。SoC 神经科学，摘录24：600,1998(摘要237.20)。

The ?-adrenergic receptors (?-ARs) are important modulators in the sympathetic control of various metabolic processes in the central (CNS) and peripheral nervous system. These receptors are localized at multiple sites throughout the nervous system, and serve as important regulators of CNS-mediated behavior and several neural functions, including mood, memory, neuroendocrine control, and stimulation of autonomic function. My laboratory has cloned, sequenced, and expressed the rat and rhesus macaque ?1-adrenergic receptor genes. We have defined the ?1-AR transcriptional start sites, promoter elements, and polyadenylation sites used for expression in the C6 glioma cell line, and have identified potential enhancer and repressor regions that influence ?1-AR expression. We have demonstrated that the inducible cAMP early repressor (ICER) is induced in C6 cells by ?1-AR agonists, and that ICER interacts with the ?1-AR promoter to down-regulate ?1-AR mRNA transcription, w ith resul tant diminution of cell surface receptor. We have also shown that the rat ?1-AR mRNA contains two functional polyadenylation sites, and that transcript selection occurs in C6 cells undergoing isoproterenol-induced ?1-AR mRNA down-regulation. This process may be regulated by post-transcriptional control mechanisms, potentially with the use of RNA stability proteins interacting with an AU-rich ?1-AR 3' untranslated region. Current research is centered on identifying genomic elements and trans-activators of ?1-AR transcription, with the use of ?1-AR luciferase-reporter recombinants, transfection assays, DNA mobility shift and DNase footprinting assays. The overall focus of this project is to precisely identify functional regulatory elements and factors involved in the regulation of the ?1-adrenergic receptor gene, and to analyze the transcriptional activation of the ?1-adrenergic receptor subtype during receptor down-regulation and hormonal stimulation. Research will initially utiliz e rodent tissues, prior to the use of nonhuman primate tissues, in the identification of ?1-AR transactivators. FUNDING NIH HL42358, and American Heart Association Established Investigator Award PUBLICATIONS Li Z, Vaidya RVA, Alvaro JD, Iredale PA, Hsu R, Hoffman G, Fitzgerald L, Curran PK, Machida CA, Fishman PH, Duman RS. Protein kinase C-mediated down-regulation of ?1-AR gene expression in rat C6 glioma cells. Mol Pharmacol 54:14-21, 1998. Yang YF, Kirigiti P, Li B, Deshmane S, Machida CA. Differential selection of ?1-adrenergic receptor transcripts during agonist-induced down-regulation. Soc Neurosci Abstr 24:600, 1998 (abstract 237.20).