Alexandrova N M, Itkes A V, Imamova L R, Chernov B K, Tulchinsky E M, Ulyanov N B, Kisselev L L
Engelhardt Institute of Molecular Biology, USSR Academy of Sciences, Moscow.
FEBS Lett. 1990 Jun 4;265(1-2):67-70. doi: 10.1016/0014-5793(90)80885-m.
Expression of c-myc proto oncogene is regulated by multiple mechanisms. Here, we report that the consensus of the regulatory region of interferon-dependent genes, GGAAAN1-3 GAAA, was found after computer search in the 5'-terminal flank of human c-myc gene in position (-76:-67). In vitro transcription of c-myc gene fragments showed that the consensus region competes with oligonucleotide GGGAAAATGAAACT for binding to specific protein(s). This oligonucleotide was shown to bind selectively the interferon-dependent positive transcription factor. Transcription of c-myc fragments lacking 5'-terminal region up to positions -101 or +71 was initiated at two sites located in the first intron. These sites did not coincide with P1 in vivo RNA cap-site. Binding of the protein factor(s) to the regulatory region of c-myc gene -76:-67 blocked the in vitro transcription initiated in the first intron.
c-myc原癌基因的表达受多种机制调控。在此,我们报告,在对人c-myc基因5'端侧翼位于(-76:-67)位置进行计算机搜索后,发现了干扰素依赖性基因调控区的共有序列GGAAAN1-3GAAA。c-myc基因片段的体外转录表明,该共有序列与寡核苷酸GGGAAAATGAAACT竞争与特定蛋白质的结合。已证明该寡核苷酸可选择性结合干扰素依赖性正转录因子。缺失5'端区域直至-101或+71位置的c-myc片段的转录起始于位于第一个内含子中的两个位点。这些位点与体内RNA帽位点P1不一致。蛋白质因子与c-myc基因-76:-67调控区的结合阻断了在第一个内含子中起始的体外转录。