Prostaglandin E-prostanoid-3 receptor activation of cyclic AMP response element-mediated gene transcription

作     者：Audoly, LP Ma, LJ Feoktistov, I De Foe, SK Breyer, MD Breyer, RM 

作者机构：Vanderbilt Univ Dept Med Div Nephrol Nashville TN 37323 USA Vanderbilt Univ Dept Med Div Cardiol Nashville TN 37323 USA Vanderbilt Univ Dept Pharmacol Nashville TN 37323 USA Vanderbilt Univ Dept Mol Physiol & Biophys Nashville TN 37323 USA Vanderbilt Univ Vet Adm Med Ctr Nashville TN 37323 USA Vanderbilt Univ Sch Med Nashville TN 37323 USA 

出 版 物：《JOURNAL OF PHARMACOLOGY AND EXPERIMENTAL THERAPEUTICS》 (药理学与实验治疗学杂志)

年 卷 期：1999年第289卷第1期

页      面：140-148页

核心收录：

学科分类：1007[医学-药学(可授医学、理学学位)] 1006[医学-中西医结合] 100706[医学-药理学] 100602[医学-中西医结合临床] 10[医学] 

基　　金：NIDDK NIH HHS [DK-37097  DK-46205] Funding Source: Medline 

主　　题：选择性剪接 氨基酸序列 钙/代谢 细胞系 环AMP/遗传学 环AMP/代谢 酶联免疫吸附测定 基因表达调控 酶学 基因 报告 分子序列数据 受体 前列腺素E/遗传学 受体 前列腺素E/代谢 反应元件/遗传学 反应元件/生理学 信号传导/生理学 转录 遗传/生理学 转染 β半乳糖苷酶类/遗传学 β半乳糖苷酶类/代谢 动物 女(雌)性 兔 

摘      要：The prostaglandin E-prostanoid (EP), receptor signals primarily through the inhibitory G protein G(i), thereby decreasing intracellular cAMP levels. To study the signal transduction properties of the rabbit EP3 receptor, five splice variants were expressed in HEK293tsA201 cells: 72A, 74A, 77A, 80A and the novel splice Variant NT, which lacks the C-terminal sequence. The ability of the EP3 receptor splice variants to modulate expression of a beta-galactosidase reporter gene under the control of a promoter containing cAMP response elements (CRE) was assessed. Each splice variant induced sulprostone-mediated increase in beta-gatactosidase enzymatic activity with EC50 ranging from 0.8 nM for the NT splice variant to 3.1 nM for the 77A splice variant. Substitution of either Asp(338) with Ala, or Arg(329) with Ala or Glu in the 77A splice variant resulted in a loss of receptor-evoked increases in P-galactosidase activity, whereas substitution of Lys(300) with alanine had no effect on signal transduction. These phenotypes correlate with the inhibition of cAMP generation by direct cAMP measurement. Signal transduction was insensitive to pretreatment of cells with pertussis toxin, suggesting that a nonG(i)/G(o) pathway is activated by the EP3 receptor. Direct measurement of second messenger levels confirmed that there was no increase in cAMP levels mediated by the 77A splice variant, however, there was a modest increase in intracellular Ca2+. Partial blockade of the reporter activity with kinase inhibitors demonstrates that CRE activation is mediated in part by a Ca2+-dependent kinase pathway. These data suggest that the EP, receptor signals through a novel cAMP response element binding protein/CRE pathway.