Séguin C, Prévost J
Department of Physiology, Laval University, Québec, Canada.
Nucleic Acids Res. 1988 Nov 25;16(22):10547-60. doi: 10.1093/nar/16.22.10547.
Metallothionein (MT) genes contain multiple metal regulatory elements (MREs) that are responsible for metal induction. A protein blotting procedure and a synthetic oligonucleotide have been used to identify nuclear factors interacting with a MRE (MREd) of the mouse MT-1 gene. We report the specific binding of the probe to a protein of apparent Mr 108,000 (p108). The specificity of the interaction was demonstrated by mutation analysis and competition experiments. Furthermore, the probe contains the Sp1 consensus binding sequence 5'CCGCCC3', in addition to the MRE consensus sequence, 5'TGCAC3', and we show that a Simian Virus 40 DNA fragment which contains six Sp1 binding sites did not bind p108 nor did it compete for the protein(s) interacting with MREd in a DNA footprinting assay. These results show that a metal regulatory element of the mouse MT-1 gene interacts specifically with a nuclear protein of Mr 108,000 and that this protein is distinct from the transcription factor Sp1.
金属硫蛋白（MT）基因包含多个负责金属诱导的金属调节元件（MREs）。一种蛋白质印迹法和一种合成寡核苷酸已被用于鉴定与小鼠MT-1基因的一个MRE（MREd）相互作用的核因子。我们报道了该探针与一种表观分子量为108,000的蛋白质（p108）的特异性结合。通过突变分析和竞争实验证明了这种相互作用的特异性。此外，该探针除了含有MRE共有序列5'TGCAC3'外，还含有Sp1共有结合序列5'CCGCCC3'，并且我们表明，一个含有六个Sp1结合位点的猿猴病毒40（SV40）DNA片段既不结合p108，也不在DNA足迹分析中竞争与MREd相互作用的蛋白质。这些结果表明，小鼠MT-1基因的一个金属调节元件与一种分子量为108,000的核蛋白特异性相互作用，并且这种蛋白质与转录因子Sp1不同。
