Fodor E J, Yen T S, Rutter W J
Hormone Research Institute, University of California, San Francisco 94143.
J Biol Chem. 1988 Jul 15;263(20):9569-72.
Transcriptional enhancers are DNA sequences that regulate RNA transcription from linked promoters by binding to cellular proteins (trans-activators). In the mammalian virus SV40, initiation of transcription is controlled, in part, by a strong 72-base pair enhancer. We show that yeast cells contain a factor that binds specifically to a key DNA motif in the SV40 enhancer, the P element that is essential for viral transcription in mammalian cells. The P element shows sequence similarity to a yeast DNA transcriptional regulatory element, GCN4, that controls transcription of genes that code for amino acid biosynthetic enzymes. Insertion of the SV40 enhancer or single or multiple copies of the P element itself upstream from the cytochrome Cyc-1 promoter places the hybrid viral-yeast transcription unit under metabolic control in yeast cells. These studies suggest that the SV40 P element and its complementary trans-activator represent a conserved transcriptional control mechanism that operates on widely divergent functions in evolution.
转录增强子是一种DNA序列，通过与细胞蛋白（反式激活因子）结合来调控与其相连启动子的RNA转录。在哺乳动物病毒SV40中，转录起始部分受一个强的72碱基对增强子控制。我们发现酵母细胞含有一种因子，它能特异性结合SV40增强子中的一个关键DNA基序，即哺乳动物细胞中病毒转录所必需的P元件。P元件与酵母DNA转录调控元件GCN4具有序列相似性，GCN4控制编码氨基酸生物合成酶的基因的转录。将SV40增强子或P元件自身的单拷贝或多拷贝插入到细胞色素Cyc-1启动子上游，可使杂种病毒-酵母转录单元在酵母细胞中受代谢调控。这些研究表明，SV40 P元件及其互补的反式激活因子代表了一种保守的转录控制机制，该机制在进化过程中作用于广泛不同的功能。
