Johnston D, Oppermann H, Jackson J, Levinson W
J Biol Chem. 1980 Jul 25;255(14):6975-80.
Four proteins of Mr = 89,000, 73,000, 35,000, and 27,000 are strongly induced in chick fibroblasts by sodium arsenite. Induction of these proteins is discoordinate as a function of arsenite concentration. Kinetically, all species appear 1 h after exposure to 50 microM arsenite, after 24 and 48 h of exposure, the 27,000 protein is still synthesized extensively, whereas normal cell proteins and the three other induced proteins are greatly reduced. The four proteins are unrelated by tryptic peptide-mapping procedures. Multiple subspecies of p89, p73, and p27 were observed in two-dimensional gels. The subspecies of p73 appear to be related as determined by partial proteolytic maps as are those of p27. Two-dimensional gel analysis of in vitro translation products from rabbit reticulocyte lysates primed with mRNA from uninduced and induced cells reveals that the amount of translatable mRNA specific for these proteins is increase by induction. This increase is attributable to new mRNA synthesis since actinomycin D prevent induction and new bands of RNA (Mr = 0.9 X 10(6) and 1.3 X 10(6)) appear in methyl mercury gels of oligo(dT) selected RNA from induced cells. These bands are assigned to p73 and p89 based on translation of electroeluted RNA from a similar preparative gel. A comparison is made between induction of these proteins and the heat shock response in Drosophilla melanogaster.
亚砷酸钠可强烈诱导鸡成纤维细胞中分子量分别为89,000、73,000、35,000和27,000的四种蛋白质。这些蛋白质的诱导与亚砷酸盐浓度不成比例。从动力学角度来看，在暴露于50微摩尔亚砷酸盐1小时后，所有种类的蛋白质都出现了；在暴露24小时和48小时后，分子量为27,000的蛋白质仍大量合成，而正常细胞蛋白质和其他三种诱导蛋白则大幅减少。通过胰蛋白酶肽图谱分析，这四种蛋白质没有相关性。在二维凝胶中观察到了p89、p73和p27的多个亚类。通过部分蛋白水解图谱确定，p73的亚类与p27的亚类似乎相关。用未诱导和诱导细胞的mRNA引发兔网织红细胞裂解物进行体外翻译产物的二维凝胶分析表明, 这些蛋白质特异性的可翻译mRNA的量因诱导而增加。这种增加归因于新的mRNA合成，因为放线菌素D可阻止诱导，并且在从诱导细胞中选择的寡聚（dT）RNA的甲基汞凝胶中出现了新的RNA条带（分子量分别为0.9×10⁶和1.3×10⁶）。根据从类似制备凝胶中电洗脱RNA的翻译情况，将这些条带分别对应于p73和p89。对这些蛋白质的诱导与黑腹果蝇的热休克反应进行了比较。
