Cho H, Orphanides G, Sun X, Yang X J, Ogryzko V, Lees E, Nakatani Y, Reinberg D
Howard Hughes Medical Institute, Division of Nucleic Acid Enzymology, University of Medicine and Dentistry of New Jersey, Piscataway, New Jersey 08854, USA.
Mol Cell Biol. 1998 Sep;18(9):5355-63. doi: 10.1128/MCB.18.9.5355.
We have isolated a human RNA polymerase II complex that contains chromatin structure remodeling activity and histone acetyltransferase activity. This complex contains the Srb proteins, the Swi-Snf complex, and the histone acetyltransferases CBP and PCAF in addition to RNA polymerase II. Notably, the general transcription factors are absent from this complex. The complex was purified by two different methods: conventional chromatography and affinity chromatography using antibodies directed against CDK8, the human homolog of the yeast Srb10 protein. Protein interaction studies demonstrate a direct interaction between RNA polymerase II and the histone acetyltransferases p300 and PCAF. Importantly, p300 interacts specifically with the nonphosphorylated, initiation-competent form of RNA polymerase II. In contrast, PCAF interacts with the elongation-competent, phosphorylated form of RNA polymerase II.
我们分离出了一种人类RNA聚合酶II复合物，它具有染色质结构重塑活性和组蛋白乙酰转移酶活性。除RNA聚合酶II外，该复合物还包含Srb蛋白、Swi-Snf复合物以及组蛋白乙酰转移酶CBP和PCAF。值得注意的是，该复合物中不存在通用转录因子。该复合物通过两种不同方法纯化：传统色谱法和使用针对酵母Srb10蛋白的人类同源物CDK8的抗体进行亲和色谱法。蛋白质相互作用研究表明RNA聚合酶II与组蛋白乙酰转移酶p300和PCAF之间存在直接相互作用。重要的是，p300与非磷酸化的、具有起始能力的RNA聚合酶II形式特异性相互作用。相比之下，PCAF与具有延伸能力的、磷酸化形式的RNA聚合酶II相互作用。
