Wegner M, Zastrow G, Klavinius A, Schwender S, Müller F, Luksza H, Hoppe J, Wienberg J, Grummt F
Institut für Biochemie, Universität Würzburg, FRG.
Nucleic Acids Res. 1989 Dec 11;17(23):9909-32. doi: 10.1093/nar/17.23.9909.
Searching for amplification promoting sequences within the murine rDNA cistrons, we isolated two elements from the nontranscribed spacer region. These 370 bp and 423 bp long cis-acting elements, referred to as muNTS1 and muNTS2, are localized 4.1 kb and 4.6 kb upstream the RNA polymerase I transcriptional start site. They contain ca. 50 bp long AT-rich sequences that strongly interact with a protein from nuclear extracts. The protein could be purified and identified as HMG-I. A synthetic oligonucleotide encompassing the AT-rich stretch from muNTS1 is able to substitute for the muNTS elements. A similar sequence from the nontranscribed spacer of rat has previously been reported to be important for the function of the RNA polymerase I enhancer (1). Therefore the interaction of HMG I with the muNTS elements may play a role both in the stimulation of DNA amplification and transcription.
在小鼠rDNA顺反子内寻找促进扩增的序列时，我们从非转录间隔区分离出了两个元件。这些长度分别为370 bp和423 bp的顺式作用元件，称为muNTS1和muNTS2，位于RNA聚合酶I转录起始位点上游4.1 kb和4.6 kb处。它们含有约50 bp长的富含AT的序列，这些序列与核提取物中的一种蛋白质强烈相互作用。该蛋白质可以被纯化并鉴定为HMG-I。一个包含muNTS1中富含AT片段的合成寡核苷酸能够替代muNTS元件。先前报道，大鼠非转录间隔区的一个类似序列对RNA聚合酶I增强子的功能很重要(1)。因此，HMG I与muNTS元件的相互作用可能在DNA扩增和转录的刺激中都起作用。
