CRE-like response element regulates expression of rat alpha 2D-adrenergic receptor gene in vascular smooth muscle.
CRE-like response element regulates expression of rat alpha 2D-adrenergic receptor gene in vascular smooth muscle.
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CRE 样反应元件调节血管平滑肌中大鼠 α 2D 肾上腺素能受体基因的表达。
DOI：
10.1152/ajpheart.1997.273.1.h85
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
Faber,JE
中科院分区：
文献类型：
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作者：
Yang,N;Eckhart,AD;Xin,X;Faber,JE
收缩和结合研究表明，血管平滑肌细胞（SMC）根据血管节段（动脉、小动脉、静脉）差异表达α 2-肾上腺素能受体（AR）。在本研究中，α 2D-AR mRNA在腔静脉中比在主动脉中高2 - 3倍。为了了解这些细胞中α 2D-AR表达的血管调节，我们对α 2D-AR基因的5'侧翼区的2.8kb进行了测序。值得注意的特征包括两个潜在的TATA盒，一个腺苷3 '，5'-环磷酸反应元件（CRE）样结合元件和一个Sp1元件。大鼠和人类基因的比较显示，在翻译起始子甲硫氨酸5'端的1.87-kb序列上，总体同源性为74%，包括在远端TATA、CRE样和Sp1位点的完全同源性，α 2D-AR转录起始于远端TATA盒下游的鸟嘌呤核苷酸18个碱基对。报告基因构建体表现出较强的α 2D-AR启动子活性，但在大鼠主动脉和腔静脉SMC中构建体活性存在一些差异。一个重要的启动子片段的分析显示，两个地区的保护主动脉和腔静脉SMC核蛋白。这些保护区的核心序列是TGACGCTA和TATAA。前CRE-like元件赋予主动脉和腔静脉核蛋白的特异性结合。此外，启动子活性增加300%，由毛喉素或8-溴腺苷3 '，5'-环一磷酸，表明CRE样元件可以调节α 2D-AR表达血管组织。
Contractile and binding studies indicate that alpha 2-adrenergic receptors (ARs) are differentially expressed by vascular smooth muscle cells (SMCs) according to vascular segment (artery, arteriole, vein). In the present study, alpha 2D-AR mRNA was two- to threefold higher in vena cava than in aorta. To understand vascular regulation of alpha 2D-AR expression in these cells, we sequenced 2.8 kb of the 5' flanking region of the alpha 2D-AR gene. Notable features include two potential TATA boxes, an adenosine 3',5'-cyclic monophosphate response element (CRE)-like binding element, and an Sp1 element. Comparison of the rat and human genes revealed an overall homology of 74% over the 1.87-kb sequence 5' to the translation initiator methionine, including complete homology at the distal TATA, CRE-like, and Sp1 sites, alpha 2D-AR transcription starts from the guanine nucleotide 18 base pair downstream from the distal TATA box. Reporter gene constructs demonstrated strong alpha 2D-AR promoter activity, but with several differences in construct activity, in both rat aorta and vena cava SMCs. Analysis of an essential promoter fragment revealed two regions protected by aorta and vena cava SMC nuclear proteins. The core sequences of these protected regions are TGACGCTA and TATAA. The former CRE-like element conferred specific binding of both aorta and vena cava nuclear proteins. In addition, promoter activity was increased 300% by forskolin or 8-bromoadenosine 3',5'-cyclic monophosphate, indicating that the CRE-like element may regulate alpha 2D-AR expression in vascular tissue.