TISSUE-SPECIFIC AND BETA-ADRENERGIC REGULATION OF THE MITOCHONDRIAL UNCOUPLING PROTEIN GENE - CONTROL BY CIS-ACTING ELEMENTS IN THE 5'-FLANKING REGION
TISSUE-SPECIFIC AND BETA-ADRENERGIC REGULATION OF THE MITOCHONDRIAL UNCOUPLING PROTEIN GENE - CONTROL BY CIS-ACTING ELEMENTS IN THE 5'-FLANKING REGION
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DOI：
10.1210/me.7.4.497
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发表时间：
1993-04-01
影响因子：
--
通讯作者：
RICQUIER, D
中科院分区：
文献类型：
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作者：
CASSARDDOULCIER, AM;GELLY, C;RICQUIER, D
解偶联蛋白（UCP）基因的表达严格限制于产热棕色脂肪细胞，并迅速激活去甲肾上腺素释放后，冷暴露。为了确定控制该基因的顺式作用调控元件，使用杂合UCP-氯霉素乙酰转移酶报告基因构建体分析了转录起始位点上游包含4.5个酶的DNA的区域。通过比较这些报告基因在转染的棕色脂肪细胞（体外分化）、棕色前脂肪细胞、白色脂肪细胞和中国仓鼠卵巢（CHO）细胞以及转基因动物实验中的表达，获得了在该4.5-腺苷酸酶区域存在组织特异性和β-肾上腺素能反应元件的证据。转染细胞中的缺失分析表明，表现出启动子活性和组织特异性的最小区域位于-157和-57碱基对（bp）之间。在棕色脂肪细胞中，位于-2494和-2283 bp之间的211 bp激活元件是完全表达所必需的。该元件还激活棕色脂肪细胞和CHO细胞中同源-157-bp启动子的表达和异源启动子的表达。第二个区域位于激活子下游，可能位于-400和-157 bp之间，抑制CHO细胞中的UCP启动子。在转基因小鼠的氯霉素乙酰转移酶报告基因含有这些元素，表达是组织特异性和调节环境温度的变化。这些结果表明正性和负性顺式作用元件都参与了UCP基因表达的调节。
Uncoupling protein (UCP) gene expression is tightly restricted to thermogenic brown adipocytes and is rapidly activated by norepinephrine released after cold exposure. To identify cis-acting regulatory elements controlling this gene, a region encompassing 4.5 kilobases of DNA upstream of the transcription start site was analyzed using hybrid UCP-chloramphenicol acetyltransferase reporter gene constructs. Evidence for the presence of both tissue-specific and beta-adrenergic response elements in this 4.5-kilobase region was obtained by comparing the expression of these reporter genes in transfected brown adipocytes (in vitro differentiated), brown preadipocytes, white adipocytes, and Chinese hamster ovary (CHO) cells and from experiments in transgenic animals. Deletion analyses in transfected cells indicated that the minimal region exhibiting promoter activity and tissue specificity is located between -157 and -57 base pairs (bp). A 211-bp activator element located between -2494 and -2283 bp was necessary for full expression in brown adipocytes. This element also activated expression of the homologous -157-bp promoter and expression of a heterologous promoter in both brown adipocytes and CHO cells. A second region, downstream of the activator and possibly located between positions -400 and -157 bp, inhibited the UCP promoter in CHO cells. In mice transgenic for a chloramphenicol acetyltransferase reporter gene containing these elements, expression was both tissue specific and regulatable by environmental temperature changes. These results indicate that both positive and negative cis-acting elements participate in the regulation of UCP gene expression.