悬浮培养烟草细胞核中依赖 DNA 的 RNA 聚合酶 II。

DNA-dependent RNA polymerase II from nuclei of suspension-cultured tobacco cells.

机构信息

Abtellung Molekularbiologie, Gesellschaft für Biotechnologische Forschung, Mascheroder Weg 1, D-3300, Braunschweig, Germany.

出版信息

Planta. 1984 Sep;162(2):132-8. doi: 10.1007/BF00410209.

DOI:10.1007/BF00410209

PMID:24254047

Abstract

From isolated nuclei of suspension cultured cells of Nicotiana tabacum. DNA-dependent RNA polymerase II (E.C. 2.7.76) has been purified to homogeneity as evidenced by polyacrylamidegel electrophoresis under non-denaturing conditions. The purified enzyme had a specific activity of more than 15 nmol min(-1)·mg(-1) with denatured calf thymus DNA as template. Sodium-dodecyl-sulfate gel electrophoresis and protein highperformance liquid chromatography revealed a subunit composition of four proteins with molecular weights of 165 000, 135 000, 35 000 and 25 000 and with a stoichiometry of 1:1:2:2. The RNA polymerase did not exhibit any detectable proteinkinase activity. The 25 000 subunit binds ADP in a molar ratio of 1:1; it could not be decided whether this subunit has an ATPase activity or is merely an acceptor of ADP.

摘要

从悬浮培养的烟草细胞的分离核中。DNA 依赖性 RNA 聚合酶 II（EC 2.7.76）已被纯化至均一性，如在非变性条件下的聚丙烯酰胺凝胶电泳所证明。该纯化酶在以变性小牛胸腺 DNA 为模板时，具有超过 15 nmol min(-1)·mg(-1)的比活性。十二烷基硫酸钠凝胶电泳和蛋白质高效液相色谱揭示了具有分子量为 165000、135000、35000 和 25000 的四个蛋白质亚基的组成，并且具有 1:1:2:2 的化学计量比。RNA 聚合酶没有表现出任何可检测的蛋白激酶活性。25000 亚基以 1:1 的摩尔比结合 ADP；尚不能确定该亚基是否具有 ATP 酶活性，还是仅仅是 ADP 的受体。