Dahmus M E
J Biol Chem. 1981 Nov 10;256(21):11239-43.
Both calf thymus RNA polymerases I and II contain small subunits of molecular weight nearly identical with the subunits of casein kinases II and I, respectively. Antibodies prepared against calf thymus casein kinase II react with the Mr = 44,000 and 26,000 subunits of protein kinase but do not react with the Mr = 44,000 and 25,000 subunits of RNA polymerase I. These RNA polymerase I and casein kinase II subunits were purified by polyacrylamide gel electrophoresis, labeled with 125I and peptide maps generated. The tryptic peptide map of neither the Mr = 44,000 nor the 25,000 subunit of RNA polymerase I resemble the map obtained for the subunits of similar size in casein kinase II. The peptide maps generated from the Mr = 25,000 subunits of RNA polymerases I and II are, however, identical. Calf thymus RNA polymerase I, prepared by standard procedures is contaminated with casein kinase II which can be removed by rechromatography on DEAE-Sephadex. Antibodies prepared against calf thymus protein kinase I also fail to interact with the RNA polymerase II subunit of comparable size. Furthermore, peptide maps indicate that these subunits are not structurally related.
小牛胸腺RNA聚合酶I和II均含有分子量与酪蛋白激酶II和I的亚基几乎相同的小亚基。针对小牛胸腺酪蛋白激酶II制备的抗体与蛋白激酶的分子量为44,000和26,000的亚基发生反应，但不与RNA聚合酶I的分子量为44,000和25,000的亚基发生反应。这些RNA聚合酶I和酪蛋白激酶II亚基通过聚丙烯酰胺凝胶电泳纯化，用125I标记并生成肽图。RNA聚合酶I的分子量为44,000和25,000的亚基的胰蛋白酶肽图均与酪蛋白激酶II中类似大小的亚基所获得的图谱不同。然而，由RNA聚合酶I和II的分子量为25,000的亚基生成的肽图是相同的。通过标准程序制备的小牛胸腺RNA聚合酶I被酪蛋白激酶II污染，可通过在DEAE-葡聚糖凝胶上重新层析去除。针对小牛胸腺蛋白激酶I制备的抗体也不能与大小相当的RNA聚合酶II亚基相互作用。此外，肽图表明这些亚基在结构上没有相关性。
